Interpretative reading of the antibiogram Andreassen, Hans Steen; Falborg, Alina Zalounina; Paul, Mical; Sanden, Line Rugholm; Leibovici, Leonard

Size: px
Start display at page:

Download "Interpretative reading of the antibiogram Andreassen, Hans Steen; Falborg, Alina Zalounina; Paul, Mical; Sanden, Line Rugholm; Leibovici, Leonard"

Transcription

1 Aalborg Universie Inerpreaive reading of he anibiogram Andreassen, Hans Seen; Falborg, Alina Zalounina; Paul, Mical; Sanden, Line Rugholm; Leibovici, Leonard Published in: Arificial Inelligence in Medicine DOI (link o publicaion from Publisher): /j.armed Publicaion dae: 2015 Documen Version Publisher's PDF, also known as Version of record Link o publicaion from Aalborg Universiy Ciaion for published version (APA): Andreassen, S., Zalounina, A., Paul, M., Sanden, L., & Leibovici, L. (2015). Inerpreaive reading of he anibiogram: a semi-naïve Bayesian approach. Arificial Inelligence in Medicine, 65(3), DOI: /j.armed General righs Copyrigh and moral righs for he publicaions made accessible in he public poral are reained by he auhors and/or oher copyrigh owners and i is a condiion of accessing publicaions ha users recognise and abide by he legal requiremens associaed wih hese righs.? Users may download and prin one copy of any publicaion from he public poral for he purpose of privae sudy or research.? You may no furher disribue he maerial or use i for any profi-making aciviy or commercial gain? You may freely disribue he URL idenifying he publicaion in he public poral? Take down policy If you believe ha his documen breaches copyrigh please conac us a vbn@aub.aau.dk providing deails, and we will remove access o he work immediaely and invesigae your claim. Downloaded from vbn.aau.dk on: April 29, 2017

2 Arificial Inelligence in Medicine 65 (2015) Conens liss available a ScienceDirec Arificial Inelligence in Medicine j o ur na l ho mepage: Inerpreaive reading of he anibiogram a semi-naïve Bayesian approach Seen Andreassen a, Alina Zalounina a, Mical Paul b, Line Sanden a,, Leonard Leibovici c a Cener for Model-Based Medical Decision Suppor, Aalborg Universiy, Fredrik Bajers Vej 7D2, DK-9220 Aalborg, Denmark b Uni of Infecious Diseases, Rambam Healh Care Campus, HaAliya HaShniya S 8, Haifa, Israel c Sackler Faculy of Medicine Tel-Aviv Universiy, Rama Aviv 69978, Israel a r i c l e i n f o Aricle hisory: Received 10 December 2014 Received in revised form 8 July 2015 Acceped 5 Augus 2015 Keywords: Bayes heorem Bacerial infecions Animicrobial herapy Anibiogram Cross-resisance Animicrobial Sewardship a b s r a c Background: An anibiogram (ABG) gives he resuls of in viro suscepibiliy ess performed on a pahogen isolaed from a culure of a sample aken from blood or oher issues. The insiuional cross-abg consiss of he condiional probabiliy of suscepibiliy for pairs of animicrobials. This paper explores how inerpreaive reading of he isolae ABG can be used o replace and improve he prior probabiliies sored in he insiuional ABG. Probabiliies were calculaed by boh a naïve and semi-naïve Bayesian approaches, boh using he ABG for he given isolae and insiuional ABGs and cross-abgs. Mehods and Maerial: We assessed an isolae daabase from an Israeli universiy hospial wih ABGs from 3347 clinically significan blood isolaes, where on average 19 animicrobials were esed for suscepibiliy, ou of 31 animicrobials in regular use for paien reamen. For each of 14 pahogens or groups of pahogens in he daabase he average (prior) probabiliy of suscepibiliy (also called he insiuional ABG) and he insiuional cross-abg were calculaed. For each isolae, he normalized Brier disance was used as a measure of he disance beween suscepibiliy es resuls from he isolae ABG and respecively prior probabiliies and poseriori probabiliies of suscepibiliy. We used a 5-fold cross-validaion o evaluae he performance of differen approaches o predic poserior suscepibiliies. Resuls: The normalized Brier disance beween he prior probabiliies and he suscepibiliy es resuls for all isolaes in he daabase was reduced from 37.7% o 28.2% by he naïve Bayes mehod. The smalles normalized Brier disance of 25.3% was obained wih he semi-naïve min2max2 mehod, which uses he wo smalles significan odds raios and he wo larges significan odds raios expressing respecively cross-resisance and cross-suscepibiliy, calculaed from he cross-abg. Conclusion: A pracical mehod for predicing probabiliy for animicrobial suscepibiliy could be developed based on a semi-naïve Bayesian approach using saisical daa on cross-suscepibiliies and cross-resisances. The reducion in Brier disance from 37.7% o 25.3%, indicaes a significan advanage o he proposed min2max2 mehod (p < ) The Auhors. Published by Elsevier B.V. This is an open access aricle under he CC BY-NC-ND license (hp://creaivecommons.org/licenses/by-nc-nd/4.0/). 1. Inroducion When a paien presens a a hospial wih a bacerial infecion, animicrobials will be adminisered o he paien. Before he animicrobials are adminisered, samples will be aken from he Corresponding auhor a: Cener for Model-Based Medical Decision Suppor, Deparmen of Healh Science and Technology, Aalborg Universiy, Fredrik Bajers Vej 7D2, DK-9220 Aalborg, Denmark. Tel.: addresses: sa@hs.aau.dk (S. Andreassen), az@hs.aau.dk (A. Zalounina), m paul@rambam.healh.gov.il (M. Paul), sanden@hs.aau.dk (L. Sanden), leibovic@pos.au.ac.il (L. Leibovici). paien, usually boh a blood sample and a local sample from he sie of infecion, for example a urine sample if he paien is suspeced of a urinary rac infecion. Wihin a day or wo baceria are successfully isolaed from hese samples in approximaely 30% of he paiens [1]. Once isolaed, he baceria are esed for heir in viro suscepibiliy o a range of animicrobials. The es resuls are called an anibiogram (ABG), which specifies he suscepibiliy of he pahogen o each esed animicrobial. These ABGs ofen make i relevan o change he iniial empirical reamen given o he paien ino a definiive reamen, where i is known from he suscepibiliy resuls ha he isolaed baceria are suscepible o he animicrobial(s) given in he definiive reamen. hp://dx.doi.org/ /j.armed / 2015 The Auhors. Published by Elsevier B.V. This is an open access aricle under he CC BY-NC-ND license (hp://creaivecommons.org/licenses/by-nc-nd/4. 0/).

3 210 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) A any given ime a large number of animicrobials are in use in a hospial. Ou of hese only a limied se of animicrobials is esed due o pracical and economic consrains. Therefore i occasionally happens ha none of he esed animicrobials are clinically accepable. This may for example be due o allergies, o significan oxiciy, o limied gasroinesinal absorpion of he drug in severely sepic paiens, o preferences for bacericidal raher han baceriosaic animicrobials or due o preferences imposed by animicrobial sewardship programs, where for example quinolones are considered a less desirable choice relaive o cephalosporins (Danish Healh and Medicines Auhoriy, 2013) [2]. In such cases i is desirable o have addiional informaion abou he suscepibiliy of he isolaed pahogens o animicrobials for which no suscepibiliy resuls are available. Some informaion can be derived from he exper rules of he European Commiee on Animicrobial Suscepibiliy Tesing (EUCAST) [3]. EUCAST exper rules come in hree forms (edied in he ineres of simpliciy): 1. Inrinsic resisance: E.g. Rule 2.6: Pseudomonas aeruginosa is resisan o ampicillin. 2. Excepional resisance phenoypes: E.g. Rule 6.1: Saphylococcus aureus is (almos always) suscepible o vancomycin, linezolid, quinuprisin/dalfoprisin, dapomycin and igecycline. 3. Inerpreive rules: E.g. Rule 8.6: If Enerococcus spp. is resisan o ampicillin, repor as resisan o ureidopenicillins and carbapenems. The firs wo forms exend he ABG wih knowledge of respecively resisance and suscepibiliy for animicrobials, which have no been esed. The hird form exends he suscepibiliy resuls from he esed animicrobials o some of hose no esed. These rules represen an improvemen in he reporing of suscepibiliy resuls, bu cover only a very limied number of pahogen/animicrobial combinaions. I would herefore be desirable o have a compuaionally feasible mehod ha reains he advanages of he EUCAST exper rules, bu which may also provide some help when none of hese apply. This will be achieved by compiling insiuional ABGs from he isolae daabases mainained by mos clinical microbiology laboraories. For example, in he insiuional ABG compiled from he isolae daabase used in his sudy, we can read ha he prior probabiliy of Escherichia coli (E. coli) isolaes being suscepible o cefuroxime is 83%. This informaion indicaes ha prescripion of cefuroxime agains an E. coli infecion may well be useful, even if he E. coli isolae s suscepibiliy o cefuroxime has no been esed. Insiuional cross-abgs, conaining saisics on he condiional probabiliies of suscepibiliy for pairs of animicrobials can likewise be compiled. For example, in he cases where E. coli was suscepible o ofloxacin, we can read from he insiuional cross- ABG ha he condiional probabiliy of suscepibiliy o cefuroxime given suscepibiliy o ofloxacin is 96%. This can be used o prescribe cefuroxime wih good cerainy (96%) ha i will cover he E. coli infecion. This paricular case, where he quinolone, ofloxacin, may be replaced by he cephalosporin, cefuroxime, would be an example of anibioic sewardship, in line wih for example he Danish guidelines on prescribing of anibioics [2], where he use of quinolones is more resriced han he use of cephalosporins. We will refer o he condiional probabiliies as insiuional crosssuscepibiliies, or insiuional cross-resisances, if condiional on resisance. Joinly, he insiuional cross-suscepibiliies and he cross-resisances will be referred o as he insiuional cross- ABGs. The purpose of his paper is o develop a mehod of inerpreaive reading of suscepibiliy es resuls where poserior probabiliies of suscepibiliies of an isolae o unesed animicrobials are calculaed from he insiuional ABG (he priors) and he insiuional cross-abg, given he esed isolae s ABG. 2. Mehods and Maerial 2.1. The isolae daabase An isolae daabase of bacerial pahogens isolaed from blood culures aken from paiens suspeced of bacerial infecions will be used o illusrae he mehods for esimaion of poserior probabiliies of suscepibiliy. The daabase was compiled beween 2002 and 2004 a Rabin Medical Cener in Israel and includes 3347 clinically significan pahogens. The isolae daabase conains he pahogen ideniy and an ABG for each isolae. The suscepibiliy resuls are repored in he socalled S-I-R sysem. If S (sensiive) is repored as he resul of he suscepibiliy es, hen he animicrobial can eradicae he pahogen in viro and wih some excepions his will also lead o clinical success, i.e. in vivo eradicaion of he pahogen. R (resisan) is expeced o resul in clinical failure and I (inermediae) may lead o eiher. For he purposes of his paper inermediae es resuls (I) will be considered as resisan (R) Compilaion of insiuional ABGs and insiuional cross-abgs For each of he 14 pahogen groups in he isolae daabase an insiuional ABG was compiled, conaining he (prior) probabiliy of an isolae from a given group being suscepible o a given animicrobial. From he isolae daabase he cross-suscepibiliy and cross-resisance ables can also be compiled, as previously described by Zalounina e al. (2007) [4]. These ables conain condiional probabiliies of suscepibiliy for pairs of animicrobials and hey are called cross-suscepibiliies when condiional on suscepibiliy and cross-resisances, when condiional on resisance. Table IV gives an example of he compilaion of cross-suscepibiliies and cross-resisances. The cross-suscepibiliies and cross-resisances are joined ino he insiuional cross-abg ables where hey are expressed as odds raios for increased or decreased suscepibiliy (Appendix Eq. (8)). Fisher s exac es is used o deermine he significance of he odds raios. When mos isolaes are esed wih he same animicrobials he observaions are dependen, wih missing values. Therefore Fisher s exac es may underesimae he significance of some odds raios Calculaion and validaion of poserior probabiliies of suscepibiliy The poserior probabiliies will be calculaed by several versions of naïve and semi-naïve Bayesian mehods. In he naïve Bayes mehod all significan odds raios in he cross-abg will be used. In he semi-naïve Bayesian mehods only some of he significan odds raios will be used. Each mehod for calculaion of poserior probabiliies is validaed by 5-fold cross-validaion, where he isolae daabase is divided in a learning se and a validaion se. The insiuional ABGs and insiuional cross-abgs compiled from he learning se are used o calculae poserior probabiliies in he validaion se. The qualiy of he calculaed probabiliies will be assessed by deleing one suscepibiliy es resul a a ime for a given isolae in he validaion se and hen using he mehod o calculae he poserior probabiliy of suscepibiliy given he remaining suscepibiliy es resuls for ha paricular isolae. This will be repeaed for each of he es resuls for he given isolae and subsequenly for all isolaes in he 5-fold validaion se. The accuracy of he poserior probabiliies will be assessed by calculaing he disance (Appendix Eq. (11)) beween each es resul in he ABG and is calculaed poserior probabiliy. The normalized Brier disances are hen calculaed by adding all disances and normalizing (Appendix Eq. (12)).

4 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Table 1 A segmen of he isolae daabase. Isolae Pahogen OFL MER AMK 1 Acineobacer spp. R R S 2 E. coli R S R 3 Proeus spp. S NA S S = suscepible, R = resisan, NA = he suscepibiliy is no assessed The normalized Brier disance can be considered as he sandard deviaion in percen beween calculaed and esed suscepibiliies. The normalized Brier disances beween suscepibiliy es resuls and respecively prior probabiliies and poseriori probabiliies of suscepibiliy were compared using he paired samples -es (2-ailed). 3. Resuls 3.1. The isolae daabase The isolae ABGs conained a oal of suscepibiliy es resuls. A segmen of he isolae daabase is illusraed in Table 1. As an example, suscepibiliy resuls are here shown for hree animicrobials: ofloxacin (OFL), meropenem (MER) and amikacin (AMK), bu he daabase conains on average es resuls for 19 differen animicrobials per pahogen. The ABGs in he isolae daabase were used o compile he insiuional ABG of each pahogen. To avoid esimaes based on very few resuls, he pahogens were placed in 14 groups wih roughly similar suscepibiliies (Table 2). Learning suscepibiliy of a pahogen using daa from similar pahogens was previously described by Andreassen e al. (2009) [5]. The choice of animicrobials used o es suscepibiliies depended on he pahogen. Table 3 illusraes a oal of five differen ypical ses of animicrobials esed on: a) Gram negaive baceria b) Saphylococci c) Srepococci d) Enerococci and e) Oher Gram posiive baceria Table 3 shows a clear paern in he ses of animicrobials seleced for suscepibiliy es agains a pahogen. I reflecs a sraegy of: a) Only esing animicrobials known o have effec on he given pahogen. This is for example why he narrow specrum lacam, mehicillin, is no esed agains Gram negaive baceria. Table 2 Isolaes organized ino pahogen groups. Number of isolaes (%) Pahogen group Tes group 716 (21.4) E. coli Gram pos. 375 (11.2) Klebsiella spp. 266 (7.9) Acineobacer spp. 237 (7.1) Pseudomonas spp. 230 (6.9) Proeus spp. 173 (5.2) Oher Gram neg. 114 (3.4) Enerobacer spp. 454 (13.6) Saph coag posiive Saph spp. 221 (6.6) Saph coag negaive 110 (3.3) Oher srep Srep spp. 92 (2.7) Srep pneumoniae 50 (1.5) Srep viridans 283 (8.5) Enerococcus spp. Enerococcus spp. 26 (0.8) Oher Gram pos. Oher Gram pos (100) All b) Using assumpions on cross-resisance and cross-suscepibiliy o minimize he number of ess. For example he choice of esing suscepibiliy o mehicillin agains saphylococci is based on knowledge of 100% cross-resisance o oher -lacam anibioics Insiuional ABGs and insiuional cross-abgs Table 4, column 2 gives an example of how he enry for he animicrobial cefuroxime in he insiuional ABG for E. coli is compiled. The column is labeled Prior conains he number of E. coli isolaes esed agains cefuroxime, N CEF = 705; N cef = 582 is he number of isolaes esed suscepible o cefuroxime; and P(cef) = 0.83 is he prior probabiliy of E. coli being suscepible o cefuroxime. In Table 4, column 3 labeled Cross-suscep. N CEF ofl = 522 is he number of isolaes esed agains cefuroxime ha concurrenly showed suscepibiliy o ofloxacin; N cef ofl = 501 is he number of isolaes esed suscepible o cefuroxime and concurrenly suscepible o ofloxacin, and P(cef ofl) = 0.96 is hen he condiional probabiliy of suscepibiliy o cefuroxime, given ha he isolae is suscepible o ofloxacin. The column labeled Cross-resisance shows he corresponding couns and probabiliies condiional on resisance o ofloxacin. The change from he prior probabiliy of 83% o he poserior probabiliy of 96%, condiional on suscepibiliy o ofloxacin, corresponds o an odds raio OR(cef ofl) = 5.0 (Eq. (9) in he Appendix) and he change o 44% condiional on resisance corresponds o OR( cef ofl) = These wo odds raios are enered ino he cross- ABG able for E. coli. In Table 5, as an example we show he insiuional ABG for E. coli in he column labelled Prior. The columns labeled ORsus and ORres give he odds raios in he insiuional E. coli cross-abg for cefuroxime, condiional on suscepibiliy o he animicrobials lised in he rows. For example, he odds raios menioned above of 5.0 and 0.16 can be found in he Ofloxacin row. All odds raios for he ypically esed animicrobials in he E. coli example in Table 5 are significan (wih p < 0.1), excep he carbapenems and colisin. Carbapenems and colisin have prior suscepibiliies close o 100%, which implies ha resisance and hereby cross-resisance is very rarely or never observed (since he pahogen is almos always suscepible). I is also difficul o observe significan cross-suscepibiliy o hese animicrobials and also irrelevan since we already know ha he pahogen is suscepible. The odds raio condiional on suscepibiliy o cephalohin is infiniy, which implies ha suscepibiliy o cephalohin, which is a firs generaion cephalosporin guaranees suscepibiliy o cefuroxime, a second generaion cephalosporin. The odds raios, condiional o resisance o cefazidime and cefriaxone, boh hird generaion cephalosporins, and o cefepime, a fourh generaion cephalosporin, is zero or very close o zero. This means ha resisance o one of hese hree cephalosporins implies resisance o cefuroxime as well. The columns labeled ORsus and ORres in Table 5 shows only a small par of he cross-abg for E. coli. The complee insiuional ABG for E. coli conains Table 5, bu also ORsus and ORres columns for all oher animicrobials besides cefuroxime. Such daa are compiled for each of he 14 pahogen groups. The EUCAST inerpreaive rules can be enered direcly ino ables of insiuional cross-abgs, as defined in he mehods secion. For he 14 groups of pahogens and 31 animicrobials in he isolae daabase he cross-abg ables have 14*31*31*2 = enries. The inerpreaive EUCAST rules only allow 70 or 0.26% of hese enries o be filled. In comparison he saisical compilaion from he isolae daabase of enries inro he insiuional cross-abg ables allow 4682 or 17.4% of he enries o be filled.

5 212 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Table 3 ABG ses used for pahogen es groups. Anibioic Class Anibioic Gram neg. Saph spp. Srep spp. Enerococcus spp. Oher Gram pos. Penicillin Cephalosporin Carbapenem Penicillin x x x x Ampicillin x x x x Ampicillin/Sulbacam x Amoxicillin/Clavulanae x Piperacillin x Piperacillin/Tazobacam x Mehicillin x Cephalohin x x a x Cefuroxime x x a x Cefazidime x x a x Cefriaxone x x a x Cefepime x x x Erapenem b Imipenem a a a a Meropenem x x x x Monobacam Azreonam x Glycopepide Vancomycin x x x x Macrolide Eryhromycin x x x x Teracycline Aminoglycoside Quinolone Minocycline x a Teracycline x x x x x Amikacin x a x a x Genamicin x x x a x Tobramycin x Ciprofloxacin x a a a a Ofloxacin x x a a a Oher Chloramphenicol x x x x Clindamycin x x x x Colisin x Fusidic acid x x x x Rifampicin x x x x Sulfa-Trim x x x a x a: This es was phased ou during he sudy period. b: This es was phased in during he sudy period. The insiuional ABG and he odds raios in he insiuional cross-abg can be used o calculae he poserior probabiliy of suscepibiliy o an unesed animicrobial, given a suscepibiliy es resul for anoher animicrobial. If we consider a siuaion where suscepibiliy o cefuroxime of an E. coli isolae has no been esed, and ha he E. coli isolae is esed suscepible o ofloxacin, hen he poserior probabiliy of suscepibiliy cefuroxime can be calculaed. This is done by convering he prior probabiliy of suscepibiliy o cefuroxime ino odds (OD) for suscepibiliy: OD(cef) = 0.83/(1 0.83) = 4.88 (1) in accordance wih Eq. (6) in he Appendix. The poserior odds for cefuroxime, given suscepibiliy o ofloxacin, is hen calculaed as: OD(cef ofl) = OR(cef ofl) OD(cef) = = (2) in accordance wih Eq. (9) in he Appendix. Finally, he odds are convered back o a probabiliy: P(cef ofl) = OD(cef ofl)/(1 + OD(cef ofl)) = 24.41/( ) = 0.96 (3) which can be recognized as he already known condiional probabiliy from Table Mehods for calculaion of poserior probabiliies of suscepibiliy from he ABG In he ABG presened in Table 6, he suscepibiliy o cefuroxime was esed and he isolae was found o be suscepible o cefuroxime. If we again imagine ha he suscepibiliy o cefuroxime had no been esed, hen we can ask if we could have prediced he in viro suscepibiliy o cefuroxime from he oher 20 es resuls Calculaion from Bayes heorem The sraighforward soluion is o compile he 20 dimensional probabiliy marix for cefuroxime, condiional on he oher 20 resuls in he ABG. Bayes heorem can hen be used direcly o calculae he poserior probabiliy of suscepibiliy o cefuroxime. This is far from a viable soluion, because i would be impossible o populae he 2 20 elemens in his marix even wih an isolae daabase compiled over many years in a large hospial. Table 4 Suscepibiliy of E. coli o cefuroxime given knowledge of suscepibiliy o ofloxacin. Pahogen: E. coli Prior (cefuroxime) Cefuroxime condiional on ofloxacin Cross-suscepibiliy Cross-resisance Number of isolaes N CEF N cef N CEF ofl N cef ofl N CEF ofl N cef ofl Suscepibiliy P(cef) 582/705 = 0.83 P(cef ofl) 501/522 = 0.96 P(cef ofl) 79/181 = 0.44

6 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Table 5 Insiuional ABG for E. coli, odds raios for E. coli being suscepible o cefuroxime given suscepibiliy es resuls o oher animicrobials and example of an isolae ABG. Anibioic class Anibioic Prior sus. (%) Cefuroxime Isolae ABG ORsus p 0.1 ORres p 0.1 Penicillins Cephalosporins Carbapenems Penicillin Ampicillin R Ampicillin/Sulbacam Amoxicillin/Clavulanae R Piperacillin R Piperacillin/Tazobacam S Mehicillin Cephalohin R Cefuroxime 83 0 S Cefazidime S Cefriaxone S Cefepime S Erapenem NS NS Imipenem 99.8 NS NS S Meropenem 99.3 NS NS S Monobacams Azreonam S Glycopepides Macrolides Teracyclines Aminoglycosides Quinolones Vancomycin Eryhromycin Minocycline S Teracycline S Amikacin S Genamicin S Tobramycin S Ciprofloxacin S Ofloxacin S Oher Chloramphenicol Clindamycin Colisin 98.9 NS NS S Fusidic acid Rifampicin Sulfa-Trim S NS: Odds raio no significan. Blank field: Suscepibiliy o his animicrobial is no esed Calculaion from naïve Bayes If a naïve Bayes approach is used, hen he poserior probabiliy can be calculaed from he daa available in he suscepibiliy daabase, as shown in he Appendix. This is done by repeaing he procedure given by Eqs. (1) (3), excep ha he single odds raio in Eq. (2) is replaced by ORall, which is he produc of all he bolded odds raios in Table 6. When he es resul is S, we include he OR for cross-suscepibiliy and when he suscepibiliy resul is R, we include he OR for crossresisance. This resuls in he odds raio produc; ORall = 7432 and he poserior probabiliy P(cef ABG) = 100,00%. This resul indicaes a close o perfec predicion of he suscepibiliy o cefuroxime. This aemp a esimaing he poserior probabiliies is repeaed for he oher esed animicrobials, imagining one a a ime ha he es resuls are no available. The resuls are shown in Table 6 in he column labeled Naïve. For mos of he animicrobials he resuls of he suscepibiliy-esimaion are as anicipaed, bu wih a few excepions, noably he suscepibiliy o ampicillin/clavulanae, which is esimaed o 99%, even hough he resul was R (0%). A normalized Brier disance (Appendix Eq. (12)) is used as a measure of he qualiy of he poserior esimaes. This disance can be inerpreed as an average disance beween he poserior probabiliy and he acual es resul. The naïve Bayes esimaes gives a normalized Brier disance of 25.2% for he E. coli isolae considered (las row, Table 6). This can be considered as an improvemen, relaive o he normalized Brier disance for he prior esimaes, which is 29.1% Calculaion from semi-naïve Bayes The naïve Bayes assumpion is ha he suscepibiliy es resuls are muually independen. The naïve Bayes approach is known o produce overconfiden resuls, i.e. resuls oo close o 0% or 100%, if he underlying assumpion of independence is no well me, and he naïve Bayes esimaes in Table 6 could indicae ha his is he case. To manage his, a semi-naïve approach is explored. In his approach a more modes number of odds raios are used in he calculaions. We define a version of semi-naïve Bayes, called min1max1, where only he larges and he smalles odds raios from Table 5 are used o calculae he odds raio in Eq. (2). Thus, using he odds raios shaded gray in Table 5 we ge: ORmin1 max 1(cef ABG) = = 0.15 From his odds raio follows ha he poserior probabiliy of suscepibiliy o cefuroxime of 88%, which is a less exreme esimae han he esimae of 100% from he naïve Bayes mehod. The normalized Brier disance for his E. coli isolae over all animicrobials is down o 18%, which suppors he suspicion ha he naïve Bayes resuls may be overconfiden, and ha he more modes seminaïve approach may be beer han he naïve Bayes approach. In he following secion, we compare he performance of he naïve and differen versions of semi-naïve mehods Validaion of he naïve and semi-naïve Bayesian mehods To assess he qualiy of he naïve and semi-naïve poserior probabiliies of suscepibiliy, one suscepibiliy resul a a ime is

7 214 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Table 6 Anibiogram, Prior, and poserior probabiliy of suscepibiliy of an E. coli isolae. Anibioic class Anibioic Isolae ABG Probabiliy of suscepibiliy (%) Prior Naïve min1max1 Penicillins Cephalosporins Carbapenems Penicillin Ampicillin R Ampicillin/Sulbacam 53 Amoxicillin/Clavulanae R Piperacillin R Piperacillin/Tazobacam S Mehicillin Cephalohin R Cefuroxime S Cefazidime S Cefriaxone S Cefepime S Erapenem Imipenem S 99.8 Meropenem S 99.3 Monobacams Azreonam S Glycopepides Macrolides Teracyclines Aminoglycosides Quinolones Oher Vancomycin Eryhromycin Minocycline S Teracycline S Amikacin S Genamicin S Tobramycin S Ciprofloxacin S Ofloxacin S Chloramphenicol Clindamycin Colisin S 98.9 Fusidic acid Rifampicin Sulfa-Trim S Norm. Brier disance (%) Blank field: Suscepibiliy o his animicrobial is no esed. deleed from he isolae ABG and subsequenly he poserior probabiliy of suscepibiliy is calculaed from he remaining ABG resuls. This is repeaed for all he 3347 isolaes in he daabase using a 5-fold cross-validaion. For each isolae he normalized Brier disance is used o measure he disance beween suscepibiliy es resuls and respecively prior probabiliies and calculaed poserior probabiliies. Table 7 shows hese normalized Brier disances, averaged over all isolaes in he five validaion ses. The firs row presens he normalized Brier disance for prior probabiliies and he following rows presens he normalized Brier disance for differen naïve or semi-naïve Bayesian mehods. The mehods are named afer he number of odds raios used o calculae poserior probabiliies of suscepibiliy. For example, he mehod named min2max2 uses he wo smalles significan odds raios and he wo larges significan odds raios, and he min0max3 mehod includes zero odds raios on cross-resisance and he hree highes significan odds raios on cross-suscepibiliy (if hey exis). The mehods where he odds raios for cross-resisance and cross-suscepibiliy were weighed equally (shaded gray in Table 7) performed beer han boh he naïve mehod and mehods wih an unequal weighing. For example, he min0max3 mehod has a normalized Brier disance, which is even larger han he normalized Brier disance of he prior probabiliies (firs row). The min2max2 mehod performed he bes wih a normalized Brier disance of 25.3% (Ranges from 24.8% 25.6% wihin he five validaions ses). The min2max2 mehod gave a significan improvemen (p < ) when compared o he normalized Brier disance for he prior Table 7 Normalized Brier disances for poserior esimaes of suscepibiliy including differen numbers of odds raios. Number of ORs Mehod Norm. Brier disance (%) Range 0 prior min0max min1max min0max min1max min2max min0max min1max min2max min3max min0max min1max min2max min3max min4max min3max min4max All naïve probabiliies, and he disance was significanly smaller (p < 10 9 ) han he disance for he min1max1 mehod. Fig. 1 shows he performance of he min2max2 mehod on each pahogen group compared o he prior suscepibiliies from he

8 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Normalized Brier diaance 50% 40% 30% 20% 10% 0% Normalized Brier disance 40% 35% 30% 25% prior min2max2 naive prior min2max2 20% p value Fig. 1. Normalized Brier disances for each pahogen group for respecively prior suscepibiliies and he min2max2 mehod. insiuional ABG. Normalized Brier disances for each pahogen group were averaged over he five validaion ses. For Gram negaive baceria he min2max2 mehod gave an average reducion in normalized Brier disance of 13.3% from he prior suscepibiliies (from 37.3% o 23.9%). For Saphylococcus spp. he mehod reduced he disance by 12.0% (from 40.6% o 28.6%), and for he res of he Gram posiive baceria he average reducion was 3.5% (from 33.0% o 29.5%). In all he above calculaions, he poserior probabiliies were calculaed from odds raios, which are significanly differen from 1. The limi of significance was arbirarily chosen as p < 0.1. Resuls will depend on he p value chosen and herefore he poserior suscepibiliy deerminaions were carried ou wih differen p values, ranging from 0.02 o 0.5. Fig. 2 shows he mean of esimaed suscepibiliies for he five validaions ses, and he range he ses varied wihin (shaded grey). The abiliy o esimae suscepibiliies was esed using 10 differen p values (from 0.02 o 0.5) for inclusion of significan odds raios. For mos of he included suscepibiliy es resuls, poserior probabiliies of suscepibiliy could be calculaed from he oher suscepibiliy es resuls. Wih a p value of 0.02 for significance of odds raios, 71.9% of he suscepibiliies could be calculaed, and wih a p value of 0.5, 89.7% of he suscepibiliies could be calculaed. Fig. 3 illusraes ha irrespecive of p value he naïve Bayes mehod had lower normalized Brier disance han he prior probabiliies and ha he min2max2 mehod had lower normalized Brier disances han he naïve Bayes mehod. The normalized Brier disance of he naïve Bayes mehod ended o increase a lile wih he p value while he normalized Brier disance of he min2max2 mehods ended o decrease a lile wih he p value. The decrease of he normalized Brier Esimaed suscepibiliies 100% 90% 80% 70% Mean esimaed suscepibiliies 60% p value Fig. 2. Percen of he suscepibiliy resuls included in he five validaion ses for which poserior probabiliies could be calculaed by he min2max2 mehod. Fig. 3. Normalized Brier disances averaged over he five validaion ses when using respecively he prior suscepibiliies, he naïve Bayes mehod, and he min2max2 mehod o calculae probabiliies of suscepibiliy. disance of he min2max2 mehod wih he p value could be seen as an argumen for using a high p value. This should however be balanced agains he risk of obaining srange esimaes due o spurious odds raios derived from very few suscepibiliy resuls. Since he reducion in normalized Brier disance was very small for p values above 0.1, p = 0.1 may be an appropriae choice. 4. Discussion This paper explores how inerpreaive reading of he isolae ABG can be used o replace he prior probabiliies sored in he insiuional ABG, wih poserior probabiliies, which are a leas closer o suscepibiliy es resuls han he prior probabiliies. We explored boh a naïve and semi-naïve Bayesian approaches, where he poserior probabiliies were calculaed from he isolae ABG, using daa sored in he insiuional ABG and he insiuional cross-abg. A 5-fold cross-validaion showed ha he goal was achieved. The normalized Brier disance beween he prior probabiliies and he suscepibiliy es resuls for all isolaes in he daabase was reduced from 37.7% o 28.2% by he naïve Bayes mehod. The smalles normalized Brier disance of 25.3% was obained wih he semi-naïve min2max2 mehod. This illusraes ha alhough he naïve Bayes mehod acually gave an improvemen relaive o he prior probabiliies, he naïve Bayes assumpion should for his purpose be used wih resrain. The reason for a more poorly performance for mehods including more han wo odds raios (min3max3, min4max4, and naïve) is probably relaed o he naïve Bayes assumpion; ha he suscepibiliy es resuls are muually independen. The naïve Bayes approach is known o produce overconfiden resuls, i.e. resuls oo close o 0% or 100%, if he underlying assumpion of independence is no well me. The E. coli example in Table 6 indicaes ha his is he case. No surprisingly, he mehods where he odds raios for crossresisance and cross-suscepibiliy were weighed equally (shaded gray in Table 7) performed beer han boh he naïve mehod and mehods wih an unequal weighing. In oher words, giving a higher weigh o eiher cross-resisance or cross-suscepibiliy gives a disorion in he calculaed suscepibiliies. When we looked ino he performance of he min2max2 mehod on differen pahogen groups, he resuls indicaed a beer performance on Gram negaive isolaes compared o Gram posiive isolaes. This is could be relaed o a higher fracion of he cross- ABG being filled for Gram negaive pahogens, i.e. a higher fracion of significan cross-resisances and cross-suscepibiliies. Furher analysis could be done o invesigae his correlaion and he variabiliy in he fracion of he cross-abg being filled.

9 216 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) The proposed mehod can be seen as an exension of he EUCAST inerpreive exper rules because: a) The EUCAST rules are very scarce, covering only a very small par (0.26% in his sudy) of he large marix of pahogens and pairs of animicrobials. The naïve or semi-naïve Bayesian mehods cover a much larger fracion of his marix (17.4% in his sudy). b) In conras o EUCAST he proposed mehod provides an esimae of he probabiliy of suscepibiliy, which is relevan since animicrobials may be given, even when he probabiliy of suscepibiliy is smaller han 100%. c) The proposed mehod is based on saisics, local o he hospial, and will herefore adap o local microbial suscepibiliies, while EUCAST rules are based on inernaional clinical and/or microbiological evidence of varying qualiy [3]. d) EUCAST inerpreaive exper rules gives advice on anibioic suscepibiliy o anibioics in he same anibioic class as he ones esed (e.g wihin he -lacam group) [3]. The proposed mehod works across anibioic classes, as in he example wih cefuroxime and ofloxacin. This means ha he proposed mehod and he inerpreive EUCAST exper rules should be used in combinaion o ge he bes possible predicion of suscepibiliy of a pahogen. The EUCAST rules can be incorporaed as an inegraed par of he insiuional ABG. The min2max2 mehod will in combinaion wih he EUCAST rules be incorporaed ino he TREAT sysem (a compuerized decision suppor sysem for animicrobial sewardship), which have been shown o reduce inappropriae animicrobial reamens a hospials [1,6]. Inerpreaive reading of suscepibiliy resuls is expeced o furher improve performance of he sysem. A limiaion of he sudy is ha he mehods developed are approximae mehods. As poined ou already, an exac Bayesian approach would require populaion of mulidimensional condiional probabiliy marices. This is far beyond reach and in pracice he one-dimensional condiional probabiliies in he cross- ABG represens a pracical upper limi. I may herefore be considered a virue, ha useful poserior probabiliies can be calculaed from he limied informaion compiled in he suscepibiliy daabase. I may also be considered a limiaion ha only probabilisic mehods have been considered. Esimaing suscepibiliies could for example be considered as an impuaion problem, where he missing suscepibiliies should be impued from he available suscepibiliies [7]. Alernaively, classifiers could be build based on neural nes, fuzzy logic or rule inducion. We suspec ha he combinaorial explosion, which prevened a direc applicaion of Bayes heorem, will also presen problems for hese oher mehods, and we have herefore refrained from using hem. The isolae daabase used in his paper provided a raher high number of suscepibiliy resuls - on average each isolae was esed wih 19 animicrobials. Furher validaion on isolaes wih sparser suscepibiliy es resuls would help o srenghen he resuls. In general, he abiliy of he mehod o predic he suscepibiliy o an animicrobial depends on he qualiy of he relevan isolae ABG and he qualiy of he insiuional ABG and cross- ABG. To conclude, a pracical mehod for predicing probabiliy for animicrobial suscepibiliy could be developed based on a semi-naïve Bayesian approach using saisical daa on crosssuscepibiliies and cross-resisances. By using his mehod, we achieved significanly more accurae predicions of pahogen in viro suscepibiliy o animicrobials, han he prior probabiliies sored in he insiuional ABG. Conflic of ineres The auhors Seen Andreassen and Line Sanden are employed par ime a Trea Sysems, a company developing he animicrobial decision suppor sysem TREAT. Trea Sysems did no financially suppor he work. Appendix A. A.1. Calculaion of poserior probabiliy of suscepibiliy from an anibiogram We assume ha a given pahogen has an anibiogram presening a se of T animicrobials: T = {1,...,... T} and a corresponding se of suscepibiliy resuls: A T = {A 1,... A,... A T }, where A is eiher S (a suscepible resul) or R (a resisan resul). The prior probabiliy of suscepibiliy o an animicrobial B, which is no a member of he se of T animicrobials, is denoed as P(b). The corresponding probabiliy of resisance o B is denoed as P( b). The aim is o calculae he poserior probabiliy of suscepibiliy o animicrobial B given a se of suscepibiliy resuls A T, denoed as P(b A T ). A sep owards a simple approximaion of P(b A T ) can be aken by using Bayes heorem o wrie: P(b A T ) = P(A T b)p(b) (1) P(A T ) If we make he naïve Bayes assumpion of condiional independence wihin he se A T, given b, hen P(A T b) = P(A T b) (2) A Bayes inversion of P(A b) gives: P(A T b) = P(b A )P(A ) P(b) Inserion of Eqs. (2) and (3) in (1) gives: [ ] P(b AT P(b A T ) = P(A )P(A T b)p(b) ) P(b) P(b) = P(A T ) P(A T ) [ P(b AT )P(A P(b)] ) [P(A T )]P(b) = P(A T ) We now define he prior odds OD b for P(b) as: OR b = P(b)/P( b) (5) and define he poserior odds for P(b A T ) as: OD b AT = P(b A T )/P( b A T ) (6) Insering Eqs. (4) and (5) ino (6) gives: [ P(b AT P(b)] ) [P(A T )]P(b) OD b AT = [ P( b AT P(b)] ) [P(A T )]P( b) [ ] P(b AT ) P(b) P(b) = [ ] P( b AT ) = OD b P( b) P( b) The odds raio for suscepibiliy is defined as: (3) (4) OD b A OD b (7) OR b A = OD b A /OD b (8)

10 S. Andreassen e al. / Arificial Inelligence in Medicine 65 (2015) Hence eq.7 can be wrien as: OD b AT = OD b OR b A (9) Finally he poserior probabiliy can be calculaed from Eq. (6) as: P(b A T ) = OD b AT /(1 + OD b AT ) (10) using ha P( b A T ) = 1- P(b A T ). A.2. Evaluaion of he accuracy of poserior probabiliies of suscepibiliy The abiliy of a mehod o accuraely calculae poserior probabiliies of suscepibiliy was esed by removing one suscepibiliy resul A a a ime from he suscepibiliy resuls A T for a given isolae in he isolae daabase, leaving he se A T \A. Then we use he mehods o calculae P(A A T \A ) and calculae he disance o he rue resul A as he Euclidian disance: Dis = A P(A A T \A ) (11) where A has he value 1 (suscepible) or 0 (resisan). The qualiy of he poserior probabiliies provided by a given mehod was hen assessed from he normalized Brier disance [8,9] across all animicrobials A T for which a suscepibiliy resul was available: A AT Dis2 Norm.Brier dis. = (12) N AT where N AT was he number of members in he se A T. The normalized Brier disance can be inerpreed as a deviaion in percen beween he calculaed poserior probabiliy of suscepibiliy and he measured suscepibiliy es resul. References [1] Paul M, Andreassen S, Tacconelli E, Nielsen AD, Almanasreh N, Frank U, Cauda R, Leibovici L. Improving empirical anibioic reamen using TREAT, a compuerized decision suppor sysem: cluser randomized rial. Journal of Animicrobial Chemoherapy [Online] 2006;58(6): Available: hp://dx.doi.org/ /jac/dkl372. [2] Danish Healh Medicines Auhoriy. Guidelines on Prescribing Anibioics [Online] Available: hp://sundhedssyrelsen.dk/publ/publ2013/11nov/ AnibioPrescribDK En.pdf. (Accessed: 8 July 2015). [3] European Commiee on Animicrobial Suscepibiliy Tesing (EUCAST). EUCAST Exper rules 2011 [Online]. Available: hp:// rules/. (Accessed: 8 July 2015). [4] Zalounina A, Paul M, Leibovici L, Andreassen S. A sochasic model of suscepibiliy o anibioic herapy -The effecs of cross-resisance and reamen hisory. Arificial Inelligence in Medicine [Online] 2007;40(1): Available: hp://dx.doi.org/ /j.armed [5] Andreassen S, Zalounina A, Leibovici L, Paul M. Learning suscepibiliy of a pahogen using daa from similar pahogens. Mehods of Informaion in Medicine 2009;48(3): Available: hp://dx.doi.org/ / ME9226. [6] Kofoed K, Zalounina A, Andersen O, Lisby G, Paul M, Leibovici L, Andreassen S. Performance of he TREAT decision suppor sysem in an environmen wih a low prevalence of resisan pahogens. Journal of Animicrobial Chemoherapy [Online] 2009;63(2): Available: hp://dx.doi.org/ /jac/ dkn504. [7] Sinharay S, Sern H, Russell D. The use of muliple impuaion for he analysis of missing daa. Psychological Mehods [Online] 2001;6(4): Available: hp://dx.doi.org/ / x [8] Brier GW. Verificaion of forecass expressed in erms of probabiliy. Monhly Weaher Review [Online] 1950;78(1):1 3. Available: hp://dx.doi.org/ / (1950)078<0001:VOFEIT>2.0.CO;2. [9] Gneiing T, Rafery AE. Sricly proper scoring rules, predicion, and esimaion. Journal of he American Saisical Associaion [Online] 2007;102(477): Available: hp://dx.doi.org/ /

Application of different models to the lactation curves of unimproved Awassi ewes in Turkey

Application of different models to the lactation curves of unimproved Awassi ewes in Turkey Souh African Journal of Animal Science 005, 35 (4) 38 Applicaion of differen s o he lacaion curves of unimproved Awassi ewes in Turkey B. Dag 1#, I. Keskin 1 and F. Mikailsoy 1 Deparmen of Animal Science,

More information

Radiotelemetric Evaluation of the Effect of Horticultural Practices on Pine and Meadow Voles in Apple Orchards: I. Rotary Mowing

Radiotelemetric Evaluation of the Effect of Horticultural Practices on Pine and Meadow Voles in Apple Orchards: I. Rotary Mowing Universiy of Nebraska - Lincoln DigialCommons@Universiy of Nebraska - Lincoln Easern Pine and Meadow Vole Symposia Wildlife Damage Managemen, Inerne Cener for March 1981 Radioelemeric Evaluaion of he Effec

More information

CHROMID. Reading Guide

CHROMID. Reading Guide CHROMID Reading Guide CHROMID Reading Guide 2018 biomérieux, Inc. BIOMERIEUX, he BIOMERIEUX logo, and CHROMID are used, pending and/or regisered rademarks belonging o biomérieux, one of is subsidiaries,

More information

Prediction of 100-d and 305-d Milk Yields in a Multibreed Dairy Herd in Thailand Using Monthly Test-Day Records 1/

Prediction of 100-d and 305-d Milk Yields in a Multibreed Dairy Herd in Thailand Using Monthly Test-Day Records 1/ Predicion of -d and 35-d Milk Yields in a Mulibreed Dair Herd in Thailand Using Monhl Tes-Da Records / Skorn Koonawooririron *, Mauricio A. Elzo /, Sornhep Tumwasorn, and Wiro Sinala 3/ Deparmen of Animal

More information

Turning the Tide: How to Improve Antibiotic Use and Stop a Killer

Turning the Tide: How to Improve Antibiotic Use and Stop a Killer Turning he Tide: How o Improve Anibioic Use and Sop a Killer Melinda. Joyce, Pharm.D., FAPhA, FAHE ommonwealh Healh orporaion Bowling Green, Kenucky mbjoyce@chc.ne Timohy P. Gauhier, Pharm.D., BPS-AQ ID

More information

Egg production curve fitting using nonlinear models for selected and nonselected lines of White Leghorn hens

Egg production curve fitting using nonlinear models for selected and nonselected lines of White Leghorn hens Egg producion curve fiing using nonlinear models for seleced and nonseleced lines of Whie Leghorn hens R. P. Savegnago * V. A. R. Cruz * S. B. Ramos * S. L. Caeano * G. S. Schmid M. C. Ledur L. El Faro

More information

Wilson Bull., 92(3), 1980, pp

Wilson Bull., 92(3), 1980, pp GENERAL NOTES Wilson Bull., 92(3), 1980, pp. 376-381 Growh and developmen of major body componens in he Monk Parakee.- The growh raes of a considerable number of bird species have been summarized (Ricklefs,

More information

GROWTH AND DEVELOPMENT OF ECHINOCOCCUS MULTILOCULARIS IN EXPERIMENTALLY INFECTED CATS

GROWTH AND DEVELOPMENT OF ECHINOCOCCUS MULTILOCULARIS IN EXPERIMENTALLY INFECTED CATS Tile GROWTH AND DEVELOPMENT OF ECHINOCOCCUS MULTILOCULARI INFECTED CATS Auhor(s)KAMIYA Masao; OOI Hong-Kean; OKU Yuzaburo; YAGI CiaionJapanese Journal of Veerinary Research 33(3-4): 13 Issue Dae 1985-10-18

More information

Livestock management at northern latitudes. Potential economic effects of climate change in sheep farming

Livestock management at northern latitudes. Potential economic effects of climate change in sheep farming Livesock managemen a norhern laiudes. Poenial economic effecs of climae change in sheep farming Anne B. Johannesen Deparmen of Economics Norwegian Universiy of Science and Technology (NTNU) Anders Nielsen

More information

The economics of sheep farming at northern latitudes. Potential effects of climate change

The economics of sheep farming at northern latitudes. Potential effects of climate change The economics of sheep farming a norhern laiudes. Poenial effecs of climae change Absrac The paper sudies he economy and ecology of sheep farming when climae change and uncerainy may affec vegeaion quaniy.

More information

WORKING PAPER SERIES

WORKING PAPER SERIES ISSN 1503-299 WORKING PAPER SERIES No. 4/2013 Livesock managemen a norhern laiudes. Poenial economic effecs of climae change in sheep farming Anne Borge Johannesen Deparmen of Economics, Norwegian Universiy

More information

SOME CHARACTERISTICS OF THE IMMUNE RESPONSE TO SPOROZOITES OF SIMIAN AND HUMAN MALARIA

SOME CHARACTERISTICS OF THE IMMUNE RESPONSE TO SPOROZOITES OF SIMIAN AND HUMAN MALARIA SOME CHARACTERISTICS OF THE IMMUNE RESPONSE TO SPOROZOITES OF SIMIAN AND HUMAN MALARIA Ruh S. Nussenzweig, M.D., Ph.D.;2 and David Chen, M.A., Ph.D.3 The ques for a vaccine agains malaria has focused considerable

More information

Canine Parvovirus Infection in South American Canids

Canine Parvovirus Infection in South American Canids ^1. '' la Reprined from he JOURNAL O THE AERICAN VETERINARY EDICAL ASSOCIATION, Vol. 177, No. 9, Pages 779-78. American Veerinary edical Associaion, 1980. All Righs Reserved. Canine Parvovirus Infecion

More information

MURIEL NEY-NIFLE*, CARLOS BERNSTEIN*, JUAN C. REBOREDA and ALEX KACELNIK

MURIEL NEY-NIFLE*, CARLOS BERNSTEIN*, JUAN C. REBOREDA and ALEX KACELNIK Ecology 005 74, Populaion dynamics and avian brood parasiism: Blackwell Publishing, Ld. persisence and invasions in a hree-species sysem MURIEL NEY-NIFLE*, CARLOS BERNSTEIN*, JUAN C. REBOREDA and ALEX

More information

INTERNEURONES INVOLVED IN STRIDULATORY PATTERN GENERATION IN THE GRASSHOPPER CHORTHIPPUS MOLLIS (CHARP.)

INTERNEURONES INVOLVED IN STRIDULATORY PATTERN GENERATION IN THE GRASSHOPPER CHORTHIPPUS MOLLIS (CHARP.) The Journal of Experimenal Biology 199, 653 662 (1996) Prined in Grea Briain The ompany of Biologiss Limied 1996 JEB125 653 ITEREUROES IVOLVE I STRIULATORY PATTER GEERATIO I THE GRASSHOPPER HORTHIPPUS

More information

Original Research Article

Original Research Article MICRONEEDLING WITH PLATELET-RICH PLASMA VERSUS MICRONEEDLING WITH TOPICAL 5% MINOXIDIL IN PATIENTS WITH ANDROGENETIC ALOPECIA- A COMPARATIVE STUDY Kallappa C. Herakal 1, Pehani Parag Vallabhbhai 2, Karjigi

More information

An institutional perspective on externalities. The Nordic wolf re-colonization

An institutional perspective on externalities. The Nordic wolf re-colonization An insiuional perspecive on exernaliies. The Nordic wolf re-colonizaion Eivind Egeland Aronsen Aronsen Consuling N-7020 Trondheim, Norway Anders Skonhof Dep. of Economics Norwegian Universiy of Science

More information

Suggestions for appropriate agents to include in routine antimicrobial susceptibility testing

Suggestions for appropriate agents to include in routine antimicrobial susceptibility testing Suggestions for appropriate agents to include in routine antimicrobial susceptibility testing These suggestions are intended to indicate minimum sets of agents to test routinely in a diagnostic laboratory

More information

National Clinical Guideline Centre Pneumonia Diagnosis and management of community- and hospital-acquired pneumonia in adults

National Clinical Guideline Centre Pneumonia Diagnosis and management of community- and hospital-acquired pneumonia in adults National Clinical Guideline Centre Antibiotic classifications Pneumonia Diagnosis and management of community- and hospital-acquired pneumonia in adults Clinical guideline 191 Appendix N 3 December 2014

More information

PORCINE CARCASSES AND CUTS

PORCINE CARCASSES AND CUTS ECE/AGRI/135 ECONOMIC COMMISSION FOR EUROPE UN/ECE STANDARD FOR PORCINE CARCASSES AND CUTS Recommended by he Working Pary on Sandardizaion of Perishable Produce and Qualiy Developmen UNITED NATIONS New

More information

Routine internal quality control as recommended by EUCAST Version 3.1, valid from

Routine internal quality control as recommended by EUCAST Version 3.1, valid from Routine internal quality control as recommended by EUCAST Version.1, valid from 01-01-01 Escherichia coli Pseudomonas aeruginosa Staphylococcus aureus Enterococcus faecalis Streptococcus pneumoniae Haemophilus

More information

RCH antibiotic susceptibility data

RCH antibiotic susceptibility data RCH antibiotic susceptibility data The following represent RCH antibiotic susceptibility data from 2008. This data is used to inform antibiotic guidelines used at RCH. The data includes all microbiological

More information

EUCAST recommended strains for internal quality control

EUCAST recommended strains for internal quality control EUCAST recommended strains for internal quality control Escherichia coli Pseudomonas aeruginosa Staphylococcus aureus Enterococcus faecalis Streptococcus pneumoniae Haemophilus influenzae ATCC 59 ATCC

More information

Antimicrobial Susceptibility Testing: Advanced Course

Antimicrobial Susceptibility Testing: Advanced Course Antimicrobial Susceptibility Testing: Advanced Course Cascade Reporting Cascade Reporting I. Selecting Antimicrobial Agents for Testing and Reporting Selection of the most appropriate antimicrobials to

More information

STUDIES ON THE GROWTH OF THE DESERT TORTOISE (TESTUDO SULCATA) IN SUDAN: CHANGES IN MORPHOMETRICS AND BODY WEIGHT FROM HATCHING TO ONE YEAR (O+)

STUDIES ON THE GROWTH OF THE DESERT TORTOISE (TESTUDO SULCATA) IN SUDAN: CHANGES IN MORPHOMETRICS AND BODY WEIGHT FROM HATCHING TO ONE YEAR (O+) HRPTOLOGICAL JOURNAL, Vol. I, pp. 280-284 (1988) 280 STUDIS ON TH GROWTH OF TH DSRT TORTOIS (TSTUDO SULCATA) IN SUDAN: CHANGS IN MORPHOMTRICS AND BODY WIGHT FROM HATCHING TO ON YAR (O+) z. N. MAHMOUD AND

More information

Compliance of manufacturers of AST materials and devices with EUCAST guidelines

Compliance of manufacturers of AST materials and devices with EUCAST guidelines Compliance of manufacturers of AST materials and devices with EUCAST guidelines Data are based on questionnaires to manufacturers of materials and devices for antimicrobial susceptibility testing. The

More information

2016 Antibiotic Susceptibility Report

2016 Antibiotic Susceptibility Report Fairview Northland Medical Center and Elk River, Milaca, Princeton and Zimmerman Clinics 2016 Antibiotic Susceptibility Report GRAM-NEGATIVE ORGANISMS 2016 Gram-Negative Non-Urine The number of isolates

More information

2015 Antibiotic Susceptibility Report

2015 Antibiotic Susceptibility Report Citrobacter freundii Enterobacter aerogenes Enterobacter cloacae Escherichia coli Haemophilus influenzenza Klebsiella oxytoca Klebsiella pneumoniae Proteus mirabilis Pseudomonas aeruginosa Serratia marcescens

More information

Antimicrobial Susceptibility Patterns

Antimicrobial Susceptibility Patterns Antimicrobial Susceptibility Patterns KNH SURGERY Department Masika M.M. Department of Medical Microbiology, UoN Medicines & Therapeutics Committee, KNH Outline Methodology Overall KNH data Surgery department

More information

European Committee on Antimicrobial Susceptibility Testing

European Committee on Antimicrobial Susceptibility Testing European Committee on Antimicrobial Susceptibility Testing Routine and extended internal quality control as recommended by EUCAST Version 5.0, valid from 015-01-09 This document should be cited as "The

More information

Concise Antibiogram Toolkit Background

Concise Antibiogram Toolkit Background Background This toolkit is designed to guide nursing homes in creating their own antibiograms, an important tool for guiding empiric antimicrobial therapy. Information about antibiograms and instructions

More information

European Committee on Antimicrobial Susceptibility Testing

European Committee on Antimicrobial Susceptibility Testing European Committee on Antimicrobial Susceptibility Testing Routine and extended internal quality control for MIC determination and disk diffusion as recommended by EUCAST Version 8.0, valid from 018-01-01

More information

Compliance of manufacturers of AST materials and devices with EUCAST guidelines

Compliance of manufacturers of AST materials and devices with EUCAST guidelines Compliance of manufacturers of AST materials and devices with EUCAST guidelines Data are based on questionnaires to manufacturers of materials and devices for antimicrobial susceptibility testing. The

More information

a. 379 laboratories provided quantitative results, e.g (DD method) to 35.4% (MIC method) of all participants; see Table 2.

a. 379 laboratories provided quantitative results, e.g (DD method) to 35.4% (MIC method) of all participants; see Table 2. AND QUANTITATIVE PRECISION (SAMPLE UR-01, 2017) Background and Plan of Analysis Sample UR-01 (2017) was sent to API participants as a simulated urine culture for recognition of a significant pathogen colony

More information

EARS Net Report, Quarter

EARS Net Report, Quarter EARS Net Report, Quarter 4 213 March 214 Key Points for 213* Escherichia coli: The proportion of patients with invasive infections caused by E. coli producing extended spectrum β lactamases (ESBLs) increased

More information

Antibiotic. Antibiotic Classes, Spectrum of Activity & Antibiotic Reporting

Antibiotic. Antibiotic Classes, Spectrum of Activity & Antibiotic Reporting Antibiotic Antibiotic Classes, Spectrum of Activity & Antibiotic Reporting Any substance of natural, synthetic or semisynthetic origin which at low concentrations kills or inhibits the growth of bacteria

More information

Antibiotic Usage Guidelines in Hospital

Antibiotic Usage Guidelines in Hospital SUPPLEMENT TO JAPI december VOL. 58 51 Antibiotic Usage Guidelines in Hospital Camilla Rodrigues * Use of surveillance data information of Hospital antibiotic policy guidelines from Hinduja Hospital. The

More information

'l 0l'l=Acl{lNc'flPs. for small improvements toward the final behavior goal. The bad news is you can unintentionally

'l 0l'l=Acl{lNc'flPs. for small improvements toward the final behavior goal. The bad news is you can unintentionally f you ask a group of parro lovers, "Wha's he mos imporan behavlor o each pe parros?" wihou glvlng i a second hough, many peope wouc responc, Sep [J;l! Thafs wha we used o say, oo. Then one day, my daugher

More information

2012 ANTIBIOGRAM. Central Zone Former DTHR Sites. Department of Pathology and Laboratory Medicine

2012 ANTIBIOGRAM. Central Zone Former DTHR Sites. Department of Pathology and Laboratory Medicine 2012 ANTIBIOGRAM Central Zone Former DTHR Sites Department of Pathology and Laboratory Medicine Medically Relevant Pathogens Based on Gram Morphology Gram-negative Bacilli Lactose Fermenters Non-lactose

More information

Understanding the Hospital Antibiogram

Understanding the Hospital Antibiogram Understanding the Hospital Antibiogram Sharon Erdman, PharmD Clinical Professor Purdue University College of Pharmacy Infectious Diseases Clinical Pharmacist Eskenazi Health 5 Understanding the Hospital

More information

Cost high. acceptable. worst. best. acceptable. Cost low

Cost high. acceptable. worst. best. acceptable. Cost low Key words I Effect low worst acceptable Cost high Cost low acceptable best Effect high Fig. 1. Cost-Effectiveness. The best case is low cost and high efficacy. The acceptable cases are low cost and efficacy

More information

Einheit für pädiatrische Infektiologie Antibiotics - what, why, when and how?

Einheit für pädiatrische Infektiologie Antibiotics - what, why, when and how? Einheit für pädiatrische Infektiologie Antibiotics - what, why, when and how? Andrea Duppenthaler andrea.duppenthaler@insel.ch Limping patient local pain swelling tenderness warmth fever acute Osteomyelitis

More information

Childrens Hospital Antibiogram for 2012 (Based on data from 2011)

Childrens Hospital Antibiogram for 2012 (Based on data from 2011) Childrens Hospital Antibiogram for 2012 (Based on data from 2011) Prepared by: Department of Clinical Microbiology, Health Sciences Centre For further information contact: Andrew Walkty, MD, FRCPC Medical

More information

What s new in EUCAST methods?

What s new in EUCAST methods? What s new in EUCAST methods? Derek Brown EUCAST Scientific Secretary Interactive question 1 MIC determination MH-F broth for broth microdilution testing of fastidious microorganisms Gradient MIC tests

More information

A COMPARISON OF THE PALATES OF PERMIAN AND TRIASSIC DICYNODONTS

A COMPARISON OF THE PALATES OF PERMIAN AND TRIASSIC DICYNODONTS A COMPARISON OF THE PALATES OF PERMIAN AND TRIASSIC DICYNODONTS By A. R. I. Cruickshank ABSTRACT Whils cmparing he skulls f sme Triassic dicyndns wih Permian members f he family, i was ned ha he inerperygid

More information

Mercy Medical Center Des Moines, Iowa Department of Pathology. Microbiology Department Antibiotic Susceptibility January December 2016

Mercy Medical Center Des Moines, Iowa Department of Pathology. Microbiology Department Antibiotic Susceptibility January December 2016 Mercy Medical Center Des Moines, Iowa Department of Pathology Microbiology Department Antibiotic Susceptibility January December 2016 These statistics are intended solely as a GUIDE to choosing appropriate

More information

Bacterial Pathogens in Urinary Tract Infection and Antibiotic Susceptibility Pattern from a Teaching Hospital, Bengaluru, India

Bacterial Pathogens in Urinary Tract Infection and Antibiotic Susceptibility Pattern from a Teaching Hospital, Bengaluru, India ISSN: 2319-7706 Volume 4 Number 11 (2015) pp. 731-736 http://www.ijcmas.com Original Research Article Bacterial Pathogens in Urinary Tract Infection and Antibiotic Susceptibility Pattern from a Teaching

More information

Intrinsic, implied and default resistance

Intrinsic, implied and default resistance Appendix A Intrinsic, implied and default resistance Magiorakos et al. [1] and CLSI [2] are our primary sources of information on intrinsic resistance. Sanford et al. [3] and Gilbert et al. [4] have been

More information

The Basics: Using CLSI Antimicrobial Susceptibility Testing Standards

The Basics: Using CLSI Antimicrobial Susceptibility Testing Standards The Basics: Using CLSI Antimicrobial Susceptibility Testing Standards Janet A. Hindler, MCLS, MT(ASCP) UCLA Health System Los Angeles, California, USA jhindler@ucla.edu 1 Learning Objectives Describe information

More information

Antimicrobial susceptibility

Antimicrobial susceptibility Antimicrobial susceptibility PATTERNS Microbiology Department Canterbury ealth Laboratories and Clinical Pharmacology Department Canterbury District ealth Board March 2011 Contents Preface... Page 1 ANTIMICROBIAL

More information

THE NAC CHALLENGE PANEL OF ISOLATES FOR VERIFICATION OF ANTIBIOTIC SUSCEPTIBILITY TESTING METHODS

THE NAC CHALLENGE PANEL OF ISOLATES FOR VERIFICATION OF ANTIBIOTIC SUSCEPTIBILITY TESTING METHODS THE NAC CHALLENGE PANEL OF ISOLATES FOR VERIFICATION OF ANTIBIOTIC SUSCEPTIBILITY TESTING METHODS Stefanie Desmet University Hospitals Leuven Laboratory medicine microbiology stefanie.desmet@uzleuven.be

More information

جداول میکروارگانیسم های بیماریزای اولویت دار و آنتی بیوتیک های تعیین شده برای آزمایش تعیین حساسیت ضد میکروبی در برنامه مهار مقاومت میکروبی

جداول میکروارگانیسم های بیماریزای اولویت دار و آنتی بیوتیک های تعیین شده برای آزمایش تعیین حساسیت ضد میکروبی در برنامه مهار مقاومت میکروبی جداول میکروارگانیسم های بیماریزای اولویت دار و آنتی بیوتیک های تعیین شده برای آزمایش تعیین حساسیت ضد میکروبی در برنامه مهار مقاومت میکروبی ویرایش دوم بر اساس ed., 2017 CLSI M100 27 th تابستان ۶۹۳۱ تهیه

More information

CONTAGIOUS COMMENTS Department of Epidemiology

CONTAGIOUS COMMENTS Department of Epidemiology VOLUME XXIII NUMBER 1 July 2008 CONTAGIOUS COMMENTS Department of Epidemiology Bugs and Drugs Elaine Dowell, SM (ASCP), Marti Roe SM (ASCP), Ann-Christine Nyquist MD, MSPH Are the bugs winning? The 2007

More information

Recommendations for Implementation of Antimicrobial Stewardship Restrictive Interventions in Acute Hospitals in Ireland

Recommendations for Implementation of Antimicrobial Stewardship Restrictive Interventions in Acute Hospitals in Ireland Recommendations for Implementation of Antimicrobial Stewardship Restrictive Interventions in Acute Hospitals in Ireland A report by the Hospital Antimicrobial Stewardship Working Group, a subgroup of the

More information

Interactive session: adapting to antibiogram. Thong Phe Heng Vengchhun Felix Leclerc Erika Vlieghe

Interactive session: adapting to antibiogram. Thong Phe Heng Vengchhun Felix Leclerc Erika Vlieghe Interactive session: adapting to antibiogram Thong Phe Heng Vengchhun Felix Leclerc Erika Vlieghe Case 1 63 y old woman Dx: urosepsis? After 2 d: intermediate result: Gram-negative bacilli Empiric antibiotic

More information

Aberdeen Hospital. Antibiotic Susceptibility Patterns For Commonly Isolated Organisms For 2015

Aberdeen Hospital. Antibiotic Susceptibility Patterns For Commonly Isolated Organisms For 2015 Aberdeen Hospital Antibiotic Susceptibility Patterns For Commonly Isolated s For 2015 Services Laboratory Microbiology Department Aberdeen Hospital Nova Scotia Health Authority 835 East River Road New

More information

Help with moving disc diffusion methods from BSAC to EUCAST. Media BSAC EUCAST

Help with moving disc diffusion methods from BSAC to EUCAST. Media BSAC EUCAST Help with moving disc diffusion methods from BSAC to EUCAST This document sets out the main differences between the BSAC and EUCAST disc diffusion methods with specific emphasis on preparation prior to

More information

SMART WORKFLOW SOLUTIONS Introducing DxM MicroScan WalkAway System* ...

SMART WORKFLOW SOLUTIONS Introducing DxM MicroScan WalkAway System* ... SMART WORKFLOW SOLUTIONS Introducing DxM MicroScan WalkAway System* The next-generation MicroScan WalkAway System combines proven technology and reliability with enhanced ease-of-use features to streamline

More information

2010 ANTIBIOGRAM. University of Alberta Hospital and the Stollery Children s Hospital

2010 ANTIBIOGRAM. University of Alberta Hospital and the Stollery Children s Hospital 2010 ANTIBIOGRAM University of Alberta Hospital and the Stollery Children s Hospital Medical Microbiology Department of Laboratory Medicine and Pathology Table of Contents Page Introduction..... 2 Antibiogram

More information

Performance of the TREAT decision support system in an environment with a low prevalence of resistant pathogens

Performance of the TREAT decision support system in an environment with a low prevalence of resistant pathogens Journal of Antimicrobial Chemotherapy Advance Access published December 17, 2008 Journal of Antimicrobial Chemotherapy doi:10.1093/jac/dkn504 Performance of the TREAT decision support system in an environment

More information

BACTERIAL SUSCEPTIBILITY REPORT: 2016 (January 2016 December 2016)

BACTERIAL SUSCEPTIBILITY REPORT: 2016 (January 2016 December 2016) BACTERIAL SUSCEPTIBILITY REPORT: 2016 (January 2016 December 2016) VA Palo Alto Health Care System April 14, 2017 Trisha Nakasone, PharmD, Pharmacy Service Russell Ryono, PharmD, Public Health Surveillance

More information

2009 ANTIBIOGRAM. University of Alberta Hospital and the Stollery Childrens Hospital

2009 ANTIBIOGRAM. University of Alberta Hospital and the Stollery Childrens Hospital 2009 ANTIBIOGRAM University of Alberta Hospital and the Stollery Childrens Hospital Division of Medical Microbiology Department of Laboratory Medicine and Pathology 2 Table of Contents Page Introduction.....

More information

EUCAST-and CLSI potency NEO-SENSITABS

EUCAST-and CLSI potency NEO-SENSITABS EUCASTand CLSI potency NEOSENSITABS Neo Sensitabs Page 1 / 6 Document: 6.2.0 Fastidious organisms EUCAST Interpretation zones and MIC breakpoints according to recommendations by the "Comité de l'antibiogramme

More information

Antimicrobial Update. Alison MacDonald Area Antimicrobial Pharmacist NHS Highland April 2018

Antimicrobial Update. Alison MacDonald Area Antimicrobial Pharmacist NHS Highland April 2018 Antimicrobial Update Alison MacDonald Area Antimicrobial Pharmacist NHS Highland alisonc.macdonald@nhs.net April 2018 Starter Questions Setting the scene... What if antibiotics were no longer effective?

More information

21 st Expert Committee on Selection and Use of Essential Medicines Peer Review Report Antibiotics Review

21 st Expert Committee on Selection and Use of Essential Medicines Peer Review Report Antibiotics Review (1) Have all important studies/evidence of which you are aware been included in the application? Yes No Please provide brief comments on any relevant studies that have not been included: (2) For each of

More information

TREAT Steward. Antimicrobial Stewardship software with personalized decision support

TREAT Steward. Antimicrobial Stewardship software with personalized decision support TREAT Steward TM Antimicrobial Stewardship software with personalized decision support ANTIMICROBIAL STEWARDSHIP - Interdisciplinary actions to improve patient care Quality Assurance The aim of antimicrobial

More information

Appropriate antimicrobial therapy in HAP: What does this mean?

Appropriate antimicrobial therapy in HAP: What does this mean? Appropriate antimicrobial therapy in HAP: What does this mean? Jaehee Lee, M.D. Kyungpook National University Hospital, Korea KNUH since 1907 Presentation outline Empiric antimicrobial choice: right spectrum,

More information

Antimicrobial Stewardship Strategy: Antibiograms

Antimicrobial Stewardship Strategy: Antibiograms Antimicrobial Stewardship Strategy: Antibiograms A summary of the cumulative susceptibility of bacterial isolates to formulary antibiotics in a given institution or region. Its main functions are to guide

More information

Approach to pediatric Antibiotics

Approach to pediatric Antibiotics Approach to pediatric Antibiotics Gassem Gohal FAAP FRCPC Assistant professor of Pediatrics objectives To be familiar with common pediatric antibiotics o Classification o Action o Adverse effect To discus

More information

GENERAL NOTES: 2016 site of infection type of organism location of the patient

GENERAL NOTES: 2016 site of infection type of organism location of the patient GENERAL NOTES: This is a summary of the antibiotic sensitivity profile of clinical isolates recovered at AIIMS Bhopal Hospital during the year 2016. However, for organisms in which < 30 isolates were recovered

More information

Antibiotic Updates: Part II

Antibiotic Updates: Part II Antibiotic Updates: Part II Fredrick M. Abrahamian, DO, FACEP, FIDSA Health Sciences Clinical Professor of Emergency Medicine David Geffen School of Medicine at UCLA Los Angeles, California Financial Disclosures

More information

January 2014 Vol. 34 No. 1

January 2014 Vol. 34 No. 1 January 2014 Vol. 34 No. 1. and Minimum Inhibitory Concentration (MIC) Interpretive Standards for Testing Conditions Medium: diffusion: Mueller-Hinton agar (MHA) Broth dilution: cation-adjusted Mueller-Hinton

More information

Int.J.Curr.Microbiol.App.Sci (2017) 6(3):

Int.J.Curr.Microbiol.App.Sci (2017) 6(3): International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 3 (2017) pp. 891-895 Journal homepage: http://www.ijcmas.com Original Research Article https://doi.org/10.20546/ijcmas.2017.603.104

More information

The UK 5-year AMR Strategy - a brief overview - Dr Berit Muller-Pebody National Infection Service Public Health England

The UK 5-year AMR Strategy - a brief overview - Dr Berit Muller-Pebody National Infection Service Public Health England The UK 5-year AMR Strategy - a brief overview - Dr Berit Muller-Pebody National Infection Service Public Health England Chief Medical Officer - Annual Report 2013 Antimicrobial resistance poses catastrophic

More information

Multidrug-Resistant Gram-Negative Bacterial and Carbapenem-Resistant Enterobacteriaceae Infections in the Department of the Navy: Annual Report 2013

Multidrug-Resistant Gram-Negative Bacterial and Carbapenem-Resistant Enterobacteriaceae Infections in the Department of the Navy: Annual Report 2013 Multidrug-Resistant Gram-Negative Bacterial and Carbapenem-Resistant Enterobacteriaceae Infections in the Department of the Navy: Annual Report 2013 NMCPHC-EDC-TR-139-2015 By Paul Meddaugh and Uzo Chukwuma

More information

Catalyst for Cats. The success of spaying and neutering was the. Keeping the Faith

Catalyst for Cats. The success of spaying and neutering was the. Keeping the Faith Caalys for Cas A Non-Profi Organizaion Dedicaed Alering he Fuure for Ferals N E W S L E T T E R PO Box 30331 Sana Barbara, CA 93130 Phone: (805) 685-1563 Email: caalys4cas@cox.ne Volume 20, Number 2 www.caalysforcas.org

More information

CONTAGIOUS COMMENTS Department of Epidemiology

CONTAGIOUS COMMENTS Department of Epidemiology VOLUME XXIX NUMBER 3 November 2014 CONTAGIOUS COMMENTS Department of Epidemiology Bugs and Drugs Elaine Dowell SM MLS (ASCP), Marti Roe SM MLS (ASCP), Sarah Parker MD, Jason Child PharmD, and Samuel R.

More information

ESCMID Online Lecture Library. by author

ESCMID Online Lecture Library. by author Expert rules in susceptibility testing EUCAST-ESGARS-EPASG Educational Workshop Linz, 16 19 September, 2014 Dr. Rafael Cantón Hospital Universitario Ramón y Cajal SERVICIO DE MICROBIOLOGÍA Y PARASITOLOGÍA

More information

Canadian Nosocomial Infection Surveillance Program 2018 SURVEILLANCE FOR HEALTHCARE ACQUIRED CEREBROSPINAL FLUID SHUNT ASSOCIATED INFECTIONS

Canadian Nosocomial Infection Surveillance Program 2018 SURVEILLANCE FOR HEALTHCARE ACQUIRED CEREBROSPINAL FLUID SHUNT ASSOCIATED INFECTIONS Canadian Nosocomial Infection Surveillance Program 2018 SURVEILLANCE FOR HEALTHCARE ACQUIRED CEREBROSPINAL FLUID SHUNT ASSOCIATED INFECTIONS FINAL November 29, 2017 Working Group: Joanne Langley (Chair),

More information

EAGAR Importance Rating and Summary of Antibiotic Uses in Humans in Australia

EAGAR Importance Rating and Summary of Antibiotic Uses in Humans in Australia EAGAR Importance Rating and Summary of Antibiotic Uses in Humans in Australia Background The Expert Advisory Group on Antimicrobial Resistance of the NH&MRC provides advice to Australian governments and

More information

The β- Lactam Antibiotics. Munir Gharaibeh MD, PhD, MHPE School of Medicine, The University of Jordan November 2018

The β- Lactam Antibiotics. Munir Gharaibeh MD, PhD, MHPE School of Medicine, The University of Jordan November 2018 The β- Lactam Antibiotics Munir Gharaibeh MD, PhD, MHPE School of Medicine, The University of Jordan November 2018 Penicillins. Cephalosporins. Carbapenems. Monobactams. The β- Lactam Antibiotics 2 3 How

More information

Aabo, Søren; Ricci, Antonia; Denis, Martine; Bengtsson, Björn; Dalsgaard, Anders; Rychlik, Ivan; Jensen, Annette Nygaard

Aabo, Søren; Ricci, Antonia; Denis, Martine; Bengtsson, Björn; Dalsgaard, Anders; Rychlik, Ivan; Jensen, Annette Nygaard Downloaded from orbit.dtu.dk on: Sep 04, 2018 SafeOrganic - Restrictive use of antibiotics in organic animal farming a potential for safer, high quality products with less antibiotic resistant bacteria

More information

CUMULATIVE ANTIBIOGRAM

CUMULATIVE ANTIBIOGRAM BC Children s Hospital and BC Women s Hospital & Health Centre CUMULATIVE ANTIBIOGRAM 2017 Division of Medical Microbiology Department of Pathology and Laboratory Medicine Page 1 of 5 GRAM-POSITIVE BACTERIA

More information

Antimicrobial Susceptibility Testing: The Basics

Antimicrobial Susceptibility Testing: The Basics Antimicrobial Susceptibility Testing: The Basics Susan E. Sharp, Ph.D., DABMM, FAAM Director, Airport Way Regional Laboratory Director, Regional Microbiology and Molecular Infectious Diseases Laboratories

More information

January 2014 Vol. 34 No. 1

January 2014 Vol. 34 No. 1 January 2014 Vol. 34 No. 1. and Minimal Inhibitory Concentration (MIC) Interpretive Standards for Testing Conditions Medium: diffusion: Mueller-Hinton agar (MHA) roth dilution: cation-adjusted Mueller-Hinton

More information

A retrospective analysis of urine culture results issued by the microbiology department, Teaching Hospital, Karapitiya

A retrospective analysis of urine culture results issued by the microbiology department, Teaching Hospital, Karapitiya A retrospective analysis of urine culture results issued by the microbiology department, Teaching Hospital, Karapitiya LU Edirisinghe 1, D Vidanagama 2 1 Senior Registrar in Medicine, 2 Consultant Microbiologist,

More information

Pathogens and Antibiotic Sensitivities in Post- Phacoemulsification Endophthalmitis, Kaiser Permanente, California,

Pathogens and Antibiotic Sensitivities in Post- Phacoemulsification Endophthalmitis, Kaiser Permanente, California, Pathogens and Antibiotic Sensitivities in Post- Phacoemulsification Endophthalmitis, Kaiser Permanente, California, 2007-2012 Geraldine R. Slean, MD, MS 1 ; Neal H. Shorstein, MD 2 ; Liyan Liu, MD, MS

More information

INFECTIOUS DISEASES DIAGNOSTIC LABORATORY NEWSLETTER

INFECTIOUS DISEASES DIAGNOSTIC LABORATORY NEWSLETTER INFECTIOUS DISEASES DIAGNOSTIC LABORATORY NEWSLETTER University of Minnesota Health University of Minnesota Medical Center University of Minnesota Masonic Children s Hospital May 2017 Printed herein are

More information

1. The preferred treatment option for an initial UTI episode in a 22-year-old female patient

1. The preferred treatment option for an initial UTI episode in a 22-year-old female patient 1 Chapter 79, Self-Assessment Questions 1. The preferred treatment option for an initial UTI episode in a 22-year-old female patient with normal renal function is: A. Trimethoprim-sulfamethoxazole B. Cefuroxime

More information

Original Articles. K A M S W Gunarathne 1, M Akbar 2, K Karunarathne 3, JRS de Silva 4. Sri Lanka Journal of Child Health, 2011; 40(4):

Original Articles. K A M S W Gunarathne 1, M Akbar 2, K Karunarathne 3, JRS de Silva 4. Sri Lanka Journal of Child Health, 2011; 40(4): Original Articles Analysis of blood/tracheal culture results to assess common pathogens and pattern of antibiotic resistance at medical intensive care unit, Lady Ridgeway Hospital for Children K A M S

More information

microbiology testing services

microbiology testing services microbiology testing services You already know Spectra Laboratories for a wide array of dialysis-related testing services. Now get to know us for your microbiology needs. As the leading provider of renal-specific

More information

Lack of Change in Susceptibility of Pseudomonas aeruginosa in a Pediatric Hospital Despite Marked Changes in Antibiotic Utilization

Lack of Change in Susceptibility of Pseudomonas aeruginosa in a Pediatric Hospital Despite Marked Changes in Antibiotic Utilization Infect Dis Ther (2014) 3:55 59 DOI 10.1007/s40121-014-0028-8 BRIEF REPORT Lack of Change in Susceptibility of Pseudomonas aeruginosa in a Pediatric Hospital Despite Marked Changes in Antibiotic Utilization

More information

ß-lactams. Sub-families. Penicillins. Cephalosporins. Monobactams. Carbapenems

ß-lactams. Sub-families. Penicillins. Cephalosporins. Monobactams. Carbapenems β-lactams ß-lactams Sub-families Penicillins Cephalosporins Monobactams Carbapenems ß-lactams Mode of action PBPs = Trans/Carboxy/Endo- peptidases PBP binding (Penicillin-Binding Proteins) activation of

More information

2017 Antibiogram. Central Zone. Alberta Health Services. including. Red Deer Regional Hospital. St. Mary s Hospital, Camrose

2017 Antibiogram. Central Zone. Alberta Health Services. including. Red Deer Regional Hospital. St. Mary s Hospital, Camrose 2017 Antibiogram Central Zone Alberta Health Services including Red Deer Regional Hospital St. Mary s Hospital, Camrose Introduction This antibiogram is a cumulative report of the antimicrobial susceptibility

More information

Table 1. Commonly encountered or important organisms and their usual antimicrobial susceptibilities.

Table 1. Commonly encountered or important organisms and their usual antimicrobial susceptibilities. Table 1. Commonly encountered or important organisms and their usual antimicrobial susceptibilities. Gram-positive cocci: Staphylococcus aureus: *Resistance to penicillin is almost universal. Resistance

More information

2015 Antibiogram. Red Deer Regional Hospital. Central Zone. Alberta Health Services

2015 Antibiogram. Red Deer Regional Hospital. Central Zone. Alberta Health Services 2015 Antibiogram Red Deer Regional Hospital Central Zone Alberta Health Services Introduction. This antibiogram is a cumulative report of the antimicrobial susceptibility rates of common microbial pathogens

More information

Chemotherapy of bacterial infections. Part II. Mechanisms of Resistance. evolution of antimicrobial resistance

Chemotherapy of bacterial infections. Part II. Mechanisms of Resistance. evolution of antimicrobial resistance Chemotherapy of bacterial infections. Part II. Mechanisms of Resistance evolution of antimicrobial resistance Mechanism of bacterial genetic variability Point mutations may occur in a nucleotide base pair,

More information

Isolation, identification and antimicrobial susceptibility pattern of uropathogens isolated at a tertiary care centre

Isolation, identification and antimicrobial susceptibility pattern of uropathogens isolated at a tertiary care centre International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 4 Number 10 (2015) pp. 951-955 http://www.ijcmas.com Original Research Article Isolation, identification and antimicrobial

More information

Defining Extended Spectrum b-lactamases: Implications of Minimum Inhibitory Concentration- Based Screening Versus Clavulanate Confirmation Testing

Defining Extended Spectrum b-lactamases: Implications of Minimum Inhibitory Concentration- Based Screening Versus Clavulanate Confirmation Testing Infect Dis Ther (2015) 4:513 518 DOI 10.1007/s40121-015-0094-6 BRIEF REPORT Defining Extended Spectrum b-lactamases: Implications of Minimum Inhibitory Concentration- Based Screening Versus Clavulanate

More information

2015 Antimicrobial Susceptibility Report

2015 Antimicrobial Susceptibility Report Gram negative Sepsis Outcome Programme (GNSOP) 2015 Antimicrobial Susceptibility Report Prepared by A/Professor Thomas Gottlieb Concord Hospital Sydney Jan Bell The University of Adelaide Adelaide On behalf

More information