www.wslhpt.org 2601 Agriculture Drive Madison, WI 53718 (800) 462-5261 (608) 265-1111 Shipment Date: June 15, 2015 Questions or comments should be directed to Amanda Weiss at 800-462-5261 x51 or amanda.weiss@slh.wisc.edu. Important Information: PT Central Updates: Enhancements will continue to be added throughout 2015. 90% of participants are reporting results online at PT-Central. Thank you! General instructions are located online at www.wslhpt.org. Event Name now appears on your home page next to result entry. Single SAVE function with results editable until the due date. Data submission report now contains attestation signature. Result form and Report Delivery options: The settings for your facility are noted in the demographic information in the upper right corner of your PT Central home page. Results can be entered online or by fax. Online data entry is encouraged. If the data entry option is set to web, paper result forms will not be sent with your PT sample shipments. The Report Delivery option is set to Email attachment, Email notification, or Paper. Paper reports will only be mailed to facilities that are not set up to receive emails. Please notify us at PTService@slh.wisc.edu or use the Contact Us option on the website if you wish to change your data entry or report settings. Specific Sample Notes: Module Page(s) 5090 Gram Stain (GS) 3 5030 Bacteriology Comprehensive (MCP) 4-7 5040 Bacteriology Limited (MCL) 4-7 5250 Throat / Urine Bacteriology (TU) 8-10 5260 Throat / Urine Bacteriology Limited (TUL) 8-10 5270 Urine Culture (UC) 11-15 5080 Enteric Pathogens Culture (NP) 16-19 Mark Your Calendars Now! Next Event Ships: September 14, 2015 Page 1 of 19
Please review your reports carefully before filing with the rest of your PT records. Documentation of all decisions and actions concerning incorrect responses should be maintained with your event reports to satisfy regulatory requirements. After trouble-shooting or corrective actions are completed and documented, all reports should be reviewed, signed/initialed by the appropriate personnel, and filed with your proficiency testing records to document your participation. Event Specific Information: Module 5000 (Bacterial Antigens for meningitis) BA-12 N. meningitidis Group B/ E. coli K1: This sample contained N. meningitidis Group B. Participant responses did not reach the 80% peer consensus requirement and, therefore, results were not scored. Laboratories must perform a written self-evaluation of their response to document participation for their lab surveyor. Peer specific data is included in the table below and can be useful for post event troubleshooting and documentation. BA-10 N. meningitidis Group B/E. coli K1 Participant Results Positive Negative BD Directigen 3 10 Wellcogen 1 2 Total 4 12 According to some kit manufacturers, a heating step may affect the sensitivity for the N. meningitidis Group B/E. coli K1 antigen. It is important for laboratories to reference their package inserts for proper sample handling prior to testing. Module 5220 (Neisseria gonorrhoeae): All samples were not scored due to <10 participants reporting results. All laboratories must perform a self-evaluation to document participation for their lab surveyors. Statistics can be found online in the Reports link of your PT-Central account. For the following modules, all analytes and samples achieved 80% peer consensus, matched targets, and were scored accordingly. Laboratories using methods with peer groups of n<10 were scored by the All Methods group. Module 5060 (Clostridium difficile) Module 5070 (CT/GC Detection) Module 5110 (Group A Strep Antigen) Module 5160 (Group A Strep Antigen/Strep Culture) Module 5170 (Group A Strep Culture) Module 5180 (Group B Strep) Module 5200 (MRSA/VRE) Module 5280 (Vaginal Pathogens) Your PT Evaluation Report displays your method peer group and acceptable responses. Statistics are available online under the Reports link of your PT-Central account. References 1. Versalovic, J. (ed). 2013. Manual of Clinical Microbiology. 10 th ed. ASM Press, Washington, D.C. Page 2 of 19
Module 5090 (Gram Stain) Gram Stain Organisms & Target Responses Sample Sample Contents Gram Reaction Target Morphology GS-6 Staphylococcus aureus Gram positive Cocci GS-7 Fusobacterium nucleatum Gram negative Rods/bacilli GS-8 Neisseria gonorrhoeae Gram negative Diplococci GS-9 Pseudomonas aeruginosa Gram negative Rods/bacilli GS-10 Streptococcus pneumoniae Gram positive Diplococci Sample Gram Stain Referee and Participant Results Analyte Referee Consensus Response Participant GS-6 Gram reaction 100% Gram positive 71 99 Gram negative * 1 1 Morphology 100% Cocci 71 100 GS-7 Gram reaction 100% Gram negative 72 100 Morphology 100% Rods/bacilli 100 100 GS-8 Gram reaction 100% Gram negative 72 100 Morphology 100% Diplococci 61 86 Cocci 9 13 Coccobacilli * 1 1 GS-9 Gram reaction 100% Gram negative 68 96 Gram positive * 3 4 Morphology 67% ^ Rods/bacilli 48 69 Coccobacilli 18 26 Diplococci 2 3 Cocci 2 3 GS-10 Gram reaction 76% ^ Gram positive 56 79 Gram negative 15 21 Morphology 62% ^ Diplococci 24 34 Cocci 25 36 Coccobacilli 15 21 Rods/bacilli 6 9 ^Scoring Note: Referee laboratory responses did not reach the 80% consensus requirement and, therefore, results were not scored. received a 100% non-consensus score, and laboratories must perform a written selfevaluation of their response to document participation for their lab surveyor. Sample GS-10 (S. pneumoniae) Note: Technologists should strive to report an interpretation of what is presented on the Gram stain, rather than simply report what is seen. Several participants reported Gram positive coccobacilli, which if reported on a patient would not indicate to the physician what organism may be present. Conversely, reporting Gram positive diplococci (or cocci in pairs) on a patient specimen, would give an early clue of what the organism may be. Page 3 of 19
Modules 5030 and 5040 (Bacteriology Comprehensive and Bacteriology Limited) Sample ID Requested Procedure/Analyte(s) Target Organism/Result MC-10 Group A streptococcus antigen Negative for Group A streptococcus antigen MC-11 Group A streptococcus screen Positive for Group A streptococcus MC-12 Neisseria gonorrhoeae screen Positive for Neisseria gonorrhoeae MC-13 Aerobic blood culture Leuconostoc sp. Gram stain Gram positive cocci MC-14 Urine culture Escherichia coli Gram stain Gram negative rods/bacilli Susceptibility testing Appropriate antimicrobials & susceptibilities MC-15 C. difficile antigen detection Positive for C. difficile antigen C. difficile toxin detection Positive for C. difficile toxin MC-16 MRSA screen Positive for MRSA VRE screen Negative for VRE MC-17 Group B streptococcus screen Positive for Group B streptococcus MC-18 Stool Culture Campylobacter jejuni Please note: Samples MC-15 through MC-18 are not included in module 5040 (Bacteriology Limited). MC-10 (Group A streptococcus antigen detection), MC-11 (Group A streptococcus culture), and MC-12 (Neisseria gonorrhoeae screen): All analytes and samples achieved 80% peer consensus, matched targets, and were scored accordingly. Laboratories using methods with peer groups of n<10 were scored by the All Methods group. MC-13 (Aerobic blood culture): Sample contained Leuconostoc species >100,000 CFU/Loop. Referee consensus: Culture = 19% ^ Gram reaction = N/A Gram morphology = N/A Leuconostoc species 1 < 2 Gram positive cocci 4 6 Growth observed (would refer) 7 11 Growth 1 < 2 No Growth 48 75 Staphylococcus epidermidis group 2 3 Staphylococcus coagulase negative 1 < 2 Gram Stain Responses Gram positive 26 96 Gram negative 1 4 Cocci 25 96 Diplococci 1 4 Page 4 of 19
^Scoring Note: Referee laboratory responses did not reach the 80% consensus requirement and, therefore, results were not scored. received a 100% non-consensus score, and laboratories must perform a written selfevaluation of their response to document participation for their lab surveyor. Many labs (75%) observed No growth for this sample both on conventional agar plates and in blood culture bottles. One participant reported obtaining growth only in a thioglycollate broth. It is unclear why the strain in sample MC-13 failed to grow for most labs. Typically, Leuconostoc species do not require any special media and will grow as small alpha-hemolytic or nonhemolytic colonies on blood agar. Leuconostoc species are Gram positive cocci, typically presenting as pairs or chains. Leuconostoc species are catalase negative, PYR and LAP negative, and resistant to vancomycin. Leuconostoc species have been reported as the causal agents in bacteremia, brain abscesses, peritoneal fluid infections and wounds. MC-14 (Urine culture): Sample contained Escherichia coli >1,000,000 CFU/Loop and Lactobacillus species <10,000 CFU/Loop. Referee consensus: Culture = 100% Gram reaction = 100% Gram morphology = 96% Escherichia coli 85 Gram negative rod/bacilli 1 Gram negative bacteria 1 100 Growth observed (would refer) 15 Growth 26 Gram Stain Responses Gram negative 95 100 Rods/bacilli 91 96 Coccobacilli * 4 4 MC-15 (Clostridium difficile toxin/antigen), MC-16 (MRSA/VRE screen), and MC-17 (Group B streptococcus screen): All analytes and samples achieved 80% consensus, matched targets, and were scored accordingly. Laboratories using methods with peer groups of n<10 were scored by the All Methods group. MC-16 Scoring Note (MRSA screen): This sample contained methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive S. aureus (MSSA). The MRSA was detected by 81% of participants. Colonies of MRSA and MSSA may appear as different morphologies on routine media. When PT samples or patient specimens grow multiple morphologies of S. aureus, all colony types should be screened for methicillin resistance. Page 5 of 19
MC-18 (Stool for enteric pathogens): Sample contained Campylobacter jejuni >1,000,000 CFU/Loop and Klebsiella pneumoniae >100,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not identified in stool 36 Campylobacter 100% Campylobacter jejuni 10 Campylobacter species 26 Positive by Immunoassay 12 Not identified in stool * 2 E. coli O157:H7 100% Not identified in stool 47 Not detected 1 Normal Flora isolated ^ 1 Plesiomonas 100% Not identified in stool 34 Salmonella 100% Not identified in stool 55 Normal Flora isolated ^ 1 Shigella 100% Not identified in stool 55 Normal Flora isolated ^ 1 Vibrio 100% Not identified in stool 27 Yersinia 100% No identified in stool 32 ^ This response was not scored General AST Notes: Antimicrobial Susceptibility Testing (AST) Notes Per the Centers for Medicare & Medicaid Services (CMS) requirements, all reported antimicrobials were scored using the CLSI M100-S25 (January 2015) document. AST scores were reduced, per CLIA regulations, for reporting inappropriate antimicrobials. Certain antimicrobials, interpretations, zone sizes, and/or minimum inhibitory concentration (MIC) values were not scored. There was no deduction from participants scores for these responses; however, a written self-evaluation of your response must be performed to document participation for accrediting agencies. reporting MIC values or zone sizes must give both a correct/appropriate MIC or zone size and a correct interpretation in order to receive a passing result for that antimicrobial. For example, if according to the CLSI M100 document, an MIC of 2 for ciprofloxacin should be interpreted as intermediate, and a participant reported an MIC of 2 and an interpretation of susceptible for ciprofloxacin, that antimicrobial would receive a 0%. If you have an AST result that is marked as unsatisfactory on your Evaluation Report even though your interpretation matches the accepted result, it is most likely due to an incorrect MIC or zone size response. Accepted MIC and zone size responses are not shown on your Evaluation Report. Please refer to your CLSI M100-S25 document for antimicrobial agents and their appropriate MIC values and zone sizes. Any time a laboratory is reporting an antimicrobial agent or interpretation that does not correspond to the current version of the CLSI M100 document because of in-house protocols, it should be documented in the Comments section of your results. Page 6 of 19
Sample Specific Notes: MC-14 (E. coli in urine) CLSI and FDA Breakpoint Discrepancies: The FDA breakpoints for aztreonam, cefotetan, ceftriaxone, ertapenem, imipenem, and meropenem have been revised to coincide with the current CLSI breakpoints. Information for many antimicrobials, including current FDA breakpoints, can be found at http://www.accessdata.fda.gov/scripts/cder/drugsatfda/. The manufacturers of automated susceptibility systems such as Microscan, Phoenix, and Vitek are required to follow FDA guidelines when setting MIC breakpoints for their automated systems. Some automated systems may be incapable of producing low enough MIC values to accurately follow the current guidelines. Laboratories using these systems must comment on any measures being taken to update susceptibility testing to the current guidelines. Currently, cefotaxime is the only antimicrobial reported on this sample that has a CLSI-FDA breakpoint discrepancy. Laboratories that reported an MIC value that follows FDA cefotaxime breakpoints were Not Scored if a comment was submitted informing WSLH PT that FDA guidelines were being followed. Antimicrobial Agent CLSI/FDA MIC Breakpoint Discrepancy CLSI M100-S25 MIC Breakpoints (µg/ml) FDA Breakpoints (µg/ml) S I R S I R Cefotaxime 1 2 4 8 16-32 64 Not Scored Antimicrobials: The current version of the CLSI-M100 document now has a susceptible dose dependent (SDD) interpretive category. Cefepime is the only antimicrobial in Table 2A, Enterobacteriaceae that has SDD breakpoints. MIC values in the SDD breakpoint range were not scored. The following antimicrobials were not scored due to less than 10 laboratories reporting results: cefdinir, cefixime, cefotetan, cefuroxime-sodium (parenteral), cephalothin, doripenem, fosfomycin, moxifloxacin, norfloxacin, piperacillin, ticarcillin/clavulanate, and trimethoprim. Inappropriate Antimicrobials: Appropriate antimicrobials for E. coli are listed in Table 2A, Enterobacteriaceae, of the CLSI M100-S25 document. Antimicrobials that are considered inappropriate according to this table received a 0% score. Laboratories reporting inappropriate antimicrobials are encouraged to review their susceptibility protocols and only report clinically relevant agents based on organism and specimen source. Page 7 of 19
Modules 5250 and 5260 (Throat/Urine Bacteriology and Throat/Urine Bacteriology Limited) Sample ID Requested Procedure/Analyte(s) Primary Target Organism/Result TU-8 Urine culture Aerococcus urinae TU-9 Urine culture No growth Urine culture Escherichia coli TU-10 Gram stain Gram negative rod/bacilli Susceptibility testing Appropriate antimicrobials & susceptibilities TU-11 Group A streptococcus culture Negative for Group A streptococcus TU-12 Group A streptococcus culture Positive for Group A streptococcus TU-13 Group A streptococcus antigen Negative for Group A streptococcus antigen TU-14 Group A streptococcus antigen Negative for Group A streptococcus antigen Please note: Samples TU-13 and TU-14 are not included in the Throat/Urine Bacteriology--Limited (5260) module. TU-8 (Urine culture): Sample contained Aerococcus urinae >1,000,000 CFU/Loop. Referee consensus = 83% Aerococcus species 1 Gram positive cocci 2 Gram positive bacteria 3 56 Growth observed (would refer) 9 Growth 13 No growth * 22 44 Sample Note: A. urinae has been implicated as a urinary tract pathogen in patients predisposed to infection. The organism forms small alpha-hemolytic, grey colonies on blood agar media. A. urinae is catalase negative and typically presents as clusters on a wet mount or Gram stain. TU-9 (Urine culture): Sample contained no organisms. Referee consensus = 91% No growth 44 88 Growth observed (would refer) * 1 12 Growth * 5 Page 8 of 19
TU-10 (Urine culture): Sample contained Escherichia coli >1,000,000 CFU/Loop and Lactobacillus species <10,000 CFU/Loop. Referee consensus: Culture = 100% Gram reaction = 100% Gram morphology = 96% Escherichia coli 85 Gram negative rod/bacilli 1 Gram negative bacteria 1 100 Growth observed (would refer) 15 Growth 26 Gram Stain Responses Gram negative 95 100 Rods/bacilli 91 96 Coccobacilli * 4 4 TU-11 and TU-12 (Group A streptococcus culture) and TU-13 and TU-14 (Group A streptococcus antigen detection): All samples and analytes achieved 80% peer consensus, matched targets, and were scored accordingly. Laboratories using methods with peer groups of n<10 were scored by the All Methods group. General AST Notes: Antimicrobial Susceptibility Testing (AST) Notes Per the Centers for Medicare & Medicaid Services (CMS) requirements, all reported antimicrobials were scored using the CLSI M100-S25 (January 2015) document. AST scores were reduced, per CLIA regulations, for reporting inappropriate antimicrobials. Certain antimicrobials, interpretations, zone sizes, and/or minimum inhibitory concentration (MIC) values were not scored. There was no deduction from participants scores for these responses; however, a written self-evaluation of your response must be performed to document participation for accrediting agencies. reporting MIC values or zone sizes must give both a correct/appropriate MIC or zone size and a correct interpretation in order to receive a passing result for that antimicrobial. For example, if according to the CLSI M100 document, an MIC of 2 for ciprofloxacin should be interpreted as intermediate, and a participant reported an MIC of 2 and an interpretation of susceptible for ciprofloxacin, that antimicrobial would receive a 0%. If you have an AST result that is marked as unsatisfactory on your Evaluation Report even though your interpretation matches the accepted result, it is most likely due to an incorrect MIC or zone size response. Accepted MIC and zone size Page 9 of 19
responses are not shown on your Evaluation Report. Please refer to your CLSI M100-S25 document for antimicrobial agents and their appropriate MIC values and zone sizes. Any time a laboratory is reporting an antimicrobial agent or interpretation that does not correspond to the current version of the CLSI M100 document because of in-house protocols, it should be documented in the Comments section of your results. Sample Specific Notes: TU-10 (E. coli in urine) CLSI and FDA Breakpoint Discrepancies: The FDA breakpoints for aztreonam, cefotetan, ceftriaxone, ertapenem, imipenem, and meropenem have been revised to coincide with the current CLSI breakpoints. Information for many antimicrobials, including current FDA breakpoints, can be found at http://www.accessdata.fda.gov/scripts/cder/drugsatfda/. The manufacturers of automated susceptibility systems such as Microscan, Phoenix, and Vitek are required to follow FDA guidelines when setting MIC breakpoints for their automated systems. Some automated systems may be incapable of producing low enough MIC values to accurately follow the current guidelines. Laboratories using these systems must comment on any measures being taken to update susceptibility testing to the current guidelines. Currently, cefotaxime is the only antimicrobial reported on this sample that has a CLSI-FDA breakpoint discrepancy. Laboratories that reported an MIC value that follows FDA cefotaxime breakpoints were Not Scored if a comment was submitted informing WSLH PT that FDA guidelines were being followed. Antimicrobial Agent CLSI/FDA MIC Breakpoint Discrepancy CLSI M100-S25 MIC Breakpoints (µg/ml) FDA Breakpoints (µg/ml) S I R S I R Cefotaxime 1 2 4 8 16-32 64 Not Scored Antimicrobials: The current version of the CLSI-M100 document now has a susceptible dose dependent (SDD) interpretive category. Cefepime is the only antimicrobial in Table 2A, Enterobacteriaceae that has SDD breakpoints. MIC values in the SDD breakpoint range were not scored. The following antimicrobials were not scored due to less than 10 laboratories reporting results: cefdinir, cefixime, cefotetan, cefuroxime-sodium (parenteral), cephalothin, doripenem, fosfomycin, moxifloxacin, norfloxacin, piperacillin, ticarcillin/clavulanate, and trimethoprim. Inappropriate Antimicrobials: Appropriate antimicrobials for E. coli are listed in Table 2A, Enterobacteriaceae, of the CLSI M100-S25 document. Antimicrobials that are considered inappropriate according to this table received a 0% score. Laboratories reporting inappropriate antimicrobials are encouraged to review their susceptibility protocols and only report clinically relevant agents based on organism and specimen source. Page 10 of 19
Sample ID Requested Procedure/Analyte(s) Module 5270 (Urine culture) Target Organism/Result UC-6 Urine culture Klebsiella pneumoniae Gram stain Gram negative rods/bacilli UC-7 Urine culture Aerococcus urinae Gram stain Gram positive cocci UC-8 Urine culture No growth UC-9 Urine culture Candida albicans Gram stain Gram positive yeast Urine culture Escherichia coli UC-10 Gram stain Gram negative rods/bacilli Susceptibility testing Appropriate antimicrobials & susceptibilities Scoring Note: The Gram stain portion of samples UC-6, UC-7 and UC-9 was Not Scored since less than 10 participant laboratories performed this testing. All participants received a 100% score for the Gram stain portion of these samples and must perform a written self-evaluation of their responses to document participation for their lab surveyor. Gram Stain Note: Please note that the Gram stain portion of these samples is meant to demonstrate a laboratory s ability to perform and read Gram stains. Even if a Gram stain was not required to identify a certain organism in a urine culture challenge, it is to the laboratory s advantage to use these samples to show proficiency in Gram staining if it is a procedure being performed in the facility. Please contact the coordinator at 800-462-5261 x51 with any questions. UC-6: Sample contained Klebsiella pneumoniae >100,000 CFU/Loop and Lactobacillus sp. <10,000 CFU/Loop. Peer consensus (Culture) = 93% Scoring Note: Less than 10 referee laboratories submitted results for this sample; therefore, it was scored by peer consensus. Klebsiella pneumoniae 4 Klebsiella species 1 Growth observed (would refer) 3 93 Growth 6 Enterobacter species * 1 7 Gram Stain Responses (Not Scored) Gram negative 4 80 Gram positive 1 20 Rods/bacilli 4 100 Page 11 of 19
UC-7: Sample contained Aerococcus urinae >1,000,000 CFU/Loop. Referee consensus = 83% Aerococcus species 1 Gram positive cocci 2 Gram positive bacteria 3 56 Growth observed (would refer) 9 Growth 13 No growth * 22 44 Gram Stain Responses (Not Scored) Gram positive 3 75 Gram negative 1 25 Cocci 3 100 Sample Note: A. urinae has been implicated as a urinary tract pathogen in patients predisposed to infection. The organism forms small alpha-hemolytic, grey colonies on blood agar media. A. urinae is catalase negative and typically presents as clusters on a wet mount or Gram stain. UC-8: Sample contained no organisms. Referee consensus = 91% No growth 44 88 Growth observed (would refer) * 1 12 Growth * 5 Page 12 of 19
UC-9: Sample contained Candida albicans >100,000 CFU/Loop and Corynebacterium species <10,000 CFU/Loop. Peer consensus (Culture) = 80% Scoring Note: Less than 10 referee laboratories submitted results for this sample; therefore, it was scored by peer consensus. Candida albicans 1 Yeast present 2 Growth observed (would refer) 4 80 Growth 5 Staphylococcus coagulase negative * 1 7 Pseudomonas species * 1 7 No growth * 1 7 Gram Stain Responses (Not Scored) Gram positive 5 100 Yeast 3 75 Cocci 1 25 UC-10: Sample contained Escherichia coli >1,000,000 CFU/Loop and Lactobacillus species <10,000 CFU/Loop. Referee consensus: Culture = 100% Gram reaction = 100% Gram morphology = 96% Escherichia coli 85 Gram negative rod/bacilli 1 Gram negative bacteria 1 100 Growth observed (would refer) 15 Growth 26 Gram Stain Responses Gram negative 95 100 Rods/bacilli 91 96 Coccobacilli * 4 4 Page 13 of 19
Antimicrobial Susceptibility Testing (AST) Notes General AST Notes: Per the Centers for Medicare & Medicaid Services (CMS) requirements, all reported antimicrobials were scored using the CLSI M100-S25 (January 2015) document. AST scores were reduced, per CLIA regulations, for reporting inappropriate antimicrobials. Certain antimicrobials, interpretations, zone sizes, and/or minimum inhibitory concentration (MIC) values were not scored. There was no deduction from participants scores for these responses; however, a written self-evaluation of your response must be performed to document participation for accrediting agencies. reporting MIC values or zone sizes must give both a correct/appropriate MIC or zone size and a correct interpretation in order to receive a passing result for that antimicrobial. For example, if according to the CLSI M100 document, an MIC of 2 for ciprofloxacin should be interpreted as intermediate, and a participant reported an MIC of 2 and an interpretation of susceptible for ciprofloxacin, that antimicrobial would receive a 0%. If you have an AST result that is marked as unsatisfactory on your Evaluation Report even though your interpretation matches the accepted result, it is most likely due to an incorrect MIC or zone size response. Accepted MIC and zone size responses are not shown on your Evaluation Report. Please refer to your CLSI M100-S25 document for antimicrobial agents and their appropriate MIC values and zone sizes. Any time a laboratory is reporting an antimicrobial agent or interpretation that does not correspond to the current version of the CLSI M100 document because of in-house protocols, it should be documented in the Comments section of your results. Sample Specific Notes: UC-10 (E. coli in urine) CLSI and FDA Breakpoint Discrepancies: The FDA breakpoints for aztreonam, cefotetan, ceftriaxone, ertapenem, imipenem, and meropenem have been revised to coincide with the current CLSI breakpoints. Information for many antimicrobials, including current FDA breakpoints, can be found at http://www.accessdata.fda.gov/scripts/cder/drugsatfda/. The manufacturers of automated susceptibility systems such as Microscan, Phoenix, and Vitek are required to follow FDA guidelines when setting MIC breakpoints for their automated systems. Some automated systems may be incapable of producing low enough MIC values to accurately follow the current guidelines. Laboratories using these systems must comment on any measures being taken to update susceptibility testing to the current guidelines. Currently, cefotaxime is the only antimicrobial reported on this sample that has a CLSI-FDA breakpoint discrepancy. Laboratories that reported an MIC value that follows FDA cefotaxime breakpoints were Not Scored if a comment was submitted informing WSLH PT that FDA guidelines were being followed. Antimicrobial Agent CLSI/FDA MIC Breakpoint Discrepancy CLSI M100-S25 MIC Breakpoints (µg/ml) FDA Breakpoints (µg/ml) S I R S I R Cefotaxime 1 2 4 8 16-32 64 Page 14 of 19
Not Scored Antimicrobials: The current version of the CLSI-M100 document now has a susceptible dose dependent (SDD) interpretive category. Cefepime is the only antimicrobial in Table 2A, Enterobacteriaceae that has SDD breakpoints. MIC values in the SDD breakpoint range were not scored. The following antimicrobials were not scored due to less than 10 laboratories reporting results: cefdinir, cefixime, cefotetan, cefuroxime-sodium (parenteral), cephalothin, doripenem, fosfomycin, moxifloxacin, norfloxacin, piperacillin, ticarcillin/clavulanate, and trimethoprim. Inappropriate Antimicrobials: Appropriate antimicrobials for E. coli are listed in Table 2A, Enterobacteriaceae, of the CLSI M100-S25 document. Antimicrobials that are considered inappropriate according to this table received a 0% score. Laboratories reporting inappropriate antimicrobials are encouraged to review their susceptibility protocols and only report clinically relevant agents based on organism and specimen source. Page 15 of 19
Module 5080 (Enteric Pathogens) Sample ID NP-6 NP-7 NP-8 NP-9 NP-10 Target Organism/Result Shigella flexneri Salmonella Javiana Campylobacter jejuni Escherichia coli O157:H7 Plesiomonas shigelloides NP-6: Sample contained Shigella flexneri >100,000 CFU/Loop, Citrobacter freundii >100,000 CFU/Loop and Escherichia coli >10,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not identified in stool 31 Campylobacter 100% Not identified in stool 31 Negative by Immunoassay 7 E. coli O157:H7 100% Not identified in stool 39 Not detected 1 Plesiomonas 100% Not identified in stool 31 Not detected 1 Salmonella 100% Not identified in stool 41 Shigella 100% Shigella flexneri 30 Shigella species 12 Detected 3 Vibrio 100% Not identified in stool 34 Yersinia 100% Not identified in stool 36 Page 16 of 19
NP-7: Sample contained Salmonella enterica subspecies enterica serotype Javiana >100,000 CFU/Loop, and Proteus mirabilis >100,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not identified in stool 31 Campylobacter 100% Not identified in stool 31 Negative by Immunoassay 7 E. coli O157:H7 100% Not identified in stool 39 Not detected 1 Plesiomonas 100% Not identified in stool 31 Not detected 1 Salmonella 100% Salmonella Javiana 18 Salmonella species 24 Detected 3 Shigella 100% Not identified in stool 42 Vibrio 100% Not identified in stool 34 Yersinia 100% Not identified in stool 36 NP-8: Sample contained Campylobacter jejuni >1,000,000 CFU/Loop and Klebsiella pneumoniae >100,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not identified in stool 31 Campylobacter 100% Campylobacter jejuni 21 Campylobacter species 10 Positive by Immunoassay 6 Detected 3 E. coli O157:H7 100% Not identified in stool 39 Not detected 1 Plesiomonas 100% Not identified in stool 31 Not detected 1 Salmonella 100% Not identified in stool 41 Shigella 100% Not identified in stool 42 Vibrio 100% Not identified in stool 34 Yersinia 100% Not identified in stool 36 Page 17 of 19
NP-9: Sample contained Escherichia coli O157:H7 >100,000 CFU/Loop and Escherichia coli (non-o157:h7) >100,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not Identified in stool 31 Campylobacter 100% Not identified in stool 31 Negative by Immunoassay 7 E. coli O157:H7 100% Escherichia coli O157:H7 20 E. coli O157 - would refer for H7 17 E. coli sorbitol-negative (would refer) 2 Not detected * 1 Plesiomonas 100% Not identified in stool 31 Not detected 1 Salmonella 100% Not identified in stool 41 Shigella 100% Not identified in stool 42 Vibrio 100% Not identified in stool 34 Yersinia 100% Not identified in stool 36 * Incorrect result Page 18 of 19
NP-10: Sample contained Plesiomonas shigelloides >10,000 CFU/Loop and Enterobacter aerogenes >10,000 CFU/Loop. Organism Referee Consensus Participant Responses No. of Aeromonas 100% Not identified in stool 31 Campylobacter 100% Not identified in stool 31 Negative by Immunoassay 7 E. coli O157:H7 100% Not identified in stool 39 Not detected 1 Plesiomonas 67% ^ Plesiomonas shigelloides 17 Detected 1 Not identified in stool 14 Salmonella 100% Not identified in stool 41 Shigella 100% Not identified in stool 42 Vibrio 100% Not identified in stool 34 Yersinia 100% Not identified in stool 36 ^Scoring Note: Referee laboratory responses did not reach the 80% consensus requirement; therefore, results were not scored. All responses for Plesiomonas received a 100% non-consensus score, and laboratories must perform a written self-evaluation of their response to document participation for their lab surveyor. Sample Note: This sample contained equal concentrations of P. shigelloides and E. aerogenes, which may have similar morphologies on blood agar. These two organisms can be distinguished by performing an oxidase test (P. shigelloides is oxidase positive). A stool culture can be screened for the presence of Aeromonas, Plesiomonas, and Vibrio species by performing a sweep oxidase test on any blood agar growth. Page 19 of 19