Antibiotic Guidelines (Adult) Classification: Clinical Guideline Lead Author: Antibiotic Steering Committee Additional author(s): Authors Division: DCSS & Tertiary Medicine Unique ID: 144TD(C)25(B3) Issue number: 5 Expiry Date: June 2019 Contents Section Who should read this document Key practice points Background What is new in this version Policy/Procedure/Guideline Clinical assessment Microbiological Investigations: Empiric treatment of SSTI MRSA Infections Other considerations in SSTI Management of cellulitis at home with intravenous antibiotics Post-operative wound Infections Prophylaxis and Treatment of Mammalian Bites Antibiotic Prophylaxis for wounds in the Emergency department Treatment of Septic Bursitis Peritoneal dialysis catheter-associated exit site infection Standards References and Supporting Documents Roles and responsibilities Document control information (Published as separate document) Document Control Policy Implementation Plan Monitoring and Review Endorsement Equality analysis Page 1 of 16
Who should read this document? This policy applies to all clinical staff involved in the prescribing of antimicrobials. Key Practice Points Clinical assessment of the severity of infection is crucial. Microbiological investigations should be undertaken as recommended below. This policy recommends empiric treatment options for adult patients with a skin and soft tissue infection including, Necrotizing fasciitis, Suspected severe PVLassociated S. aureus infection, a mammalian bite, post-operative wound infection and septic bursitis. For treatment of Diabetic Foot Infections please see the Antibiotic Guidelines Diabetic Foot Infections. Identification and management of underlying causes and risk factors for a SSTI is essential. Background Antimicrobial agents are among the most commonly prescribed drugs and account for 20% of the hospital pharmacy budget. Unfortunately, the benefits of antibiotics to individual patients are compromised by the development of bacterial drug resistance. Resistance is a natural and inevitable result of exposing bacteria to antimicrobials. Good antimicrobial prescribing will help to reduce the rate at which antibiotic resistance emerges and spreads. It will also minimise the many side effects associated with antibiotic prescribing, such as Clostridium difficile infection. It should be borne in mind that antibiotics are not needed for simple coughs and colds. In some clinical situations where infection is one of several possibilities, provided the patient is not showing signs of systemic sepsis, a wait and see approach to antibiotic prescribing is often justified while relevant cultures are performed. This document provides treatment guidelines for the most common situations in which antibiotic treatment is required. The products and regimens listed here have been selected by the Trust's Medicines Management Group on the basis of published evidence. Doses assume a weight of 60-80kg with normal renal and hepatic function. Adjustments may be needed for the treatment of some patients. This document provides treatment guidelines for the appropriate use of antibiotics. The recommendations that follow are for empirical therapy and do not cover all clinical circumstances. Alternative antimicrobial therapy may be needed in up to 20% of cases. Alternative recommendations will be made by Page 2 of 16
the microbiologist in consultation with the clinical team. This document refers to the treatment of adult patients (unless otherwise stated). What is new in this version? Addition of a new section on the use of antibiotic prophylaxis for wounds in the Emergency Department References updated Policy/ Guideline/ Protocol Microbiology of SSTI The most common infecting organisms causing skin & soft tissue infection (SSTI) are (in decreasing order of frequency): Staphylococcus aureus, other Gram positive cocci, Gram negative bacilli and anaerobes. If the causative organism(s) is (are) identified, therapy may be modified after discussion with a microbiologist. A number of different bacteria can cause necrotising fasciitis. Where a single agent is involved, this is typically a community-acquired Group A streptococcus (S. pyogenes). Polymicrobial necrotising infection typically has a mixture of anaerobic and aerobic bacteria and may follow penetrating abdominal trauma, be associated with IV drug use or arise from a perianal or Bartholin s abscess. Clinical assessment Assessment must be made to classify the severity of infection as a useful guide to admission and treatment decisions. The system below has been adapted from the CREST guidelines, 2005. The treatment of Diabetic Foot Infections is covered in a separate policy, Antibiotic Guidelines- Diabetic Foot Infections. Patient should also be assessed for risk factors for specific pathogens such as: Animal or human bite Exposure to sea or fresh water (discuss treatment options with microbiology) In addition, it is important to recognize features suggesting either necrotizing fasciitis or PVL-associated Staphylococcal infection. Page 3 of 16
Microbiological Investigations: Microbiological sampling not routinely required for Class I infections unless recent antimicrobial therapy or previous antibiotic-resistant organisms. Cultures should be taken from any skin break/ulceration or blister fluid for Class II, III and IV infections. Blood Cultures should be taken for any Class III or IV infections Recommendations for Sample collection Collect swab specimens before antimicrobial therapy where possible. Specimens should be transported and processed as soon as possible. The volume of the specimen influences the transport time that is acceptable. Large volumes of purulent material maintain the viability of anaerobes for longer. The recovery of anaerobes is compromised if the transport time exceeds 3 hr. If processing is delayed, refrigeration is preferable to storage at ambient temperature. Delays of over 48hr are undesirable for best result outcome Pus swabs; Pus when present, is preferable to a swab, particularly from deep seated infection sites. Ideally, a minimum volume of 1mL of pus should be sent. However, pus swabs are acceptable when pus is not readily available or if the area to be sampled is superficial. When using swabs, please sample the deepest part of the wound, or a representative part of the lesion. Swabbing dry crusted areas is unlikely to yield the causative pathogen. Ulcers: If specimens are taken from ulcers, the debris on the ulcer should be removed and the ulcer should be cleaned with saline. A biopsy or, preferably, a needle aspiration of the edge of the wound should then be taken. A less invasive irrigation-aspiration method may be preferred. Place the tip of a small needleless syringe under the ulcer margin and irrigate gently with at least 1 ml sterile 0.9% NaCl without preservative. After massaging the ulcer margin, repeat the irrigation with a further 1 ml sterile saline. Massage the ulcer margin again, aspirate approximately 0.25 ml of the fluid and transfer to a sterile container. Swabs should be placed in bacterial transport media. If a delay in transporting to the laboratory is anticipated, please store at 4 o c. Page 4 of 16
Empiric treatment of SSTI: Classification First Line Penicillin Allergic MRSA suspected Additional comments Class I: No signs of systemic toxicity No uncontrolled comorbidities Can usually be managed with oral antimicrobials on an outpatient basis Flucloxacillin 1g PO QDS (for patients <80kg 500mg PO QDS may be adequate ) clarithromycin 500mg BD PO doxycycline 100mg BD PO Typical Duration 5 days Class II: Systemically ill or Systemically well but with a co-morbidity such as peripheral vascular disease, chronic venous insufficiency or morbid obesity which may complicate or delay resolution of their infection. Flucloxacillin 1g IV QDS - for patients > 80kg use 2g IV QDS - maximum 1g IV QDS if egfr <15 clarithromycin 500mg IV BD Vancomycin IV Page 5 of 16 A short course of IV therapy is usually necessary. Consider referral for Home IV therapy. See Management of cellulitis at home with intravenous antibiotics below. Continuation treatment as Class I infection, typical duration: 7-14 days. Max. oral dose of flucloxacillin is 1g QDS.
Class III: Infection in a patient with evidence of systemic inflammatory response syndrome. Clinically recognised by 2 or more of: Temperature >38.3 o C or <36 o C Heart rate >90/min Resp rate >20/min or PaCO2 <4.3kPa WBC >12,000 or <4000/mm 3 or may have unstable co-morbidities that may interfere with a response to therapy or have a limb threatening infection due to vascular compromise Flucloxacillin 2g IV QDS - maximum 1g IV QDS if egfr <15 If patient is immunocompromised or has had a treatment failure with first line regimes: Piperacillin-tazobactam IV 4.5g TDS Continuation therapy should be based on culture results. If MRSA negative and no positive culture results: coamoxiclav 625mg tds, typical duration 7-14 days. Vancomycin IV If patient is immunocompromised or has had a treatment failure with first line regimes: Add oral ciprofloxacin 500mg BD Continuation therapy should be based on culture results. Vancomycin IV If patient is immunocompromised or has had a treatment failure with first line regimes: Add oral ciprofloxacin 500mg BD Continuation therapy should be based on culture results. Continuation treatment as Class I infection, typical duration: 7-14 days Page 6 of 16
Class IV: Severe sepsis (Sepsis plus hypotension {SBP<90 or MAP<70} or signs of organ dysfunction). If refractory hypotension, rash or diarrhoea is present, consider toxic shock syndrome discuss antibiotic treatment with a microbiologist. Necrotising fasciitis: Necrotising fasciitis affects the soft tissue and fascia. Infection usually extends from an area of damaged skin or a surgical wound. Signs may include severe pain which is out of proportion to cutaneous signs wooden-hard feel to subcutaneous tissues subcutaneous extension of Piperacillin-tazobactam IV 4.5g TDS plus Vancomycin IV Vancomycin IV plus clindamycin IV 900mg TDS plus meropenem 1g IV TDS Seek urgent surgical and microbiology advice vancomycin IV plus oral ciprofloxacin 500mg BD plus oral metronidazole 400mg TDS If penicillin allergic with history of anaphylaxis, vancomycin IV plus clindamycin IV 900mg TDS plus ciprofloxacin 400mg IV BD As per first line or penicillin allergic As per first line or penicillin allergic Page 7 of 16 Oral continuation therapy should be based on culture results. If MRSA negative and no positive culture results: co-amoxiclav 625mg tds, typical duration 14 days. Rationalised therapy for Group A Streptococcus infection: benzyl penicillin IV plus clindamycin IV/oral Consider IV immunoglobulin therapy if not responding
inflammation > cutaneous dark violet skin discolouration or necrosis cutaneous blistering or bullous lesions Systemic toxicity +/- altered mental state Suspected severe PVL-associated S. aureus infection: Panton-Valentine Leukocidin (PVL)- associated infection should be suspected if a patient has a necrotising SSTI, recurrent furunculosis or abscesses, or there is clustering of SSTIs within a household or social group Linezolid (only on Microbiology approval) IV or oral 600 mg BD plus clindamycin 900mg IV TDS Add oral rifampicin 600mg BD in extreme cases or if not responding to therapy As per first line As per first line Flucloxacillin or Clindamycin alone are adequate for moderate SSTI due to PVL MSSA Page 8 of 16
MRSA Infections: For microbiologically confirmed MRSA infection, treat according to reported susceptibility test results with one of the following regimens a) vancomycin IV (where infection is severe) b) Daptomycin IV (Microbiology approval required) c) linezolid IV or oral for severe cellulitis where vancomycin is contraindicated (Microbiology approval required) d) clindamycin IV or oral (where MRSA is susceptible to erythromycin) e) doxycycline in mild/moderate infection (where MRSA is susceptible to tetracycline) Other considerations in SSTI: The differential diagnosis of cellulitis includes venous thrombosis and varicose eczema (for which antibiotics are not indicated). Superficial swabs are easily contaminated by colonising bacteria, which may include both skin and faecal organisms. They are poorly predictive of the pathogenic organisms causing the underlying infection. Swab results should therefore be interpreted with caution. Good skin and wound care is important in promoting healing of skin and infected wounds. Emollients, topical antiseptics and specialist dressings may be indicated. Take advice from senior nursing staff, tissue viability specialists and podiatrists, where appropriate. Consider underlying risk factors (such as diabetes, immune deficiency, leg ulcers, lymphoedema, leg oedema, venous insufficiency, and obesity) and manage these appropriately. Diabetic patients with foot ulcers must be referred to the Podiatry service. Consider the possibility of underlying osteomyelitis: investigate and treat appropriately. Consider whether a soft tissue collection is present and needs incision and drainage. Bacterial soft tissue infection may arise secondary to fungal nail or interdigital skin infections: investigate and treat if indicated. Page 9 of 16
Management of cellulitis at home with intravenous antibiotics: Patients admitted via the Emergency department or the Emergency Assessment Unit (EAU) with cellulitis may be considered for Home/Outpatient IV Therapy (HOPT). This part of the service is provided by the Rapid Response Team (212 4226). The criteria for this service are outlined below. Please contact Rapid Response team for full details. INCLUSION CRITERIA EXCLUSION CRITERIA Cellulitis with associated lymphangitis +/- lymphadenopathy Cellulitis which has not improved with oral antibiotics or cellulitis with pyrexia Salford resident or Salford GP At least 18 years of age Access to a telephone Suitable home environment Any other acute medical problem requiring admission Evidence of severe sepsis (e.g. hypotension, new onset confusion) Cellulitis associated with suspected underlying bone or joint involvement Facial or ophthalmic cellulitis Breast cellulitis Significant mental health or substance misuse issues Post-operative wound Infections A surgical wound infection is likely to be present if two out of the following are present, Temperature above 38 0 C Pus at the operative site Spreading cellulitis around the wound. Antibiotic management as per Empiric treatment of SSTI above unless the wound is likely to be contaminated by faecal flora e.g. perianal wound or stoma site infection in which case use co-amoxiclav IV/oral in place of flucloxacillin. Prophylaxis and treatment of Mammalian bites: Mammalian bites are typically colonised by pathogens found in the oral cavities of the offending animal. These are a mixture of aerobic and anaerobic micro-organisms including; Streptococci, Staphylococci, Moraxella, Neisseria. Fusobacterium, Bacteroides, Porphyromonas, and Prevotella spp. Pasteurella multocida is a Gram-negative pathogen particularly prevalent in dog (57%) and cat (75%) bites. In cases of human bite wounds and clenched fist wounds, where HIV and Hepatitis B status is unknown, please treat patients in line with the Trust s PEP policy. Page 10 of 16
Prophylaxis of mammalian bites is indicated in the following circumstances; All cat bites, animal bites to the hand, foot and face; puncture wounds; wounds requiring surgical debridement; wounds involving joints, tendons, ligaments or suspected fracture Clenched-fist wounds (wound inflicted from a punch coming in contact with teeth) Wounds that have undergone primary closure People who are at risk of serious wound infection e.g. diabetic, cirrhotic, asplenic or immunocompromised patients People with a prosthetic valve or prosthetic joint NB: All patients with mammalian bites (especially dog bites) inflicted outside of the UK and Ireland should be considered for rabies vaccination, as should bites inflicted by bats from within UK and Irish borders. Prophylaxis of infection: Co-amoxiclav 625mg tds for 5 days. If penicillin allergic; Doxycycline 100mg bd PO and metronidazole 400mg tds PO for 5 days. Antibiotics are not usually required in newly presenting patients if the wound is greater than two days old and there is no sign of infection. Treatment of infection (wounds >2days old showing signs of infection): Mild inflammation Co-amoxiclav 625mg tds for 7-14 days. If penicillin allergic; Doxycycline 100mg bd PO and metronidazole 400mg tds PO for 7-14 days. Moderate to severe inflammation: Co-amoxiclav 1.2g tds IV Continuation treatment as for mild infection, typical duration: 7-14 days If penicillin allergic; Please consult microbiology for recommendation. Swabs should be taken from newly presenting wounds greater than two days old, that are exhibiting signs of infection, prior to commencing antibiotic therapy to assist with rationalising treatment once cultures and sensitivities are available. Page 11 of 16
Antibiotic Prophylaxis for wounds in the Emergency department: All wounds should be irrigated copiously with sterile saline, and grossly visible debris should be removed. Lacerations: For simple lacerations with no current signs of infection, antibiotic prophylaxis is NOT recommended. Proper wound preparation is the essential measure for preventing wound infection after suturing simple lacerations. Advise the patient to seek medical attention if they develop signs of infection. Patients with more complex lacerations that require more than just simple cleaning and who require referral to other specialities may require antibiotic prophylaxis. This should be discussed with the specialists on an individual patient basis. Puncture wounds: Do NOT routinely offer antibiotic prophylaxis for puncture wounds. Offer antibiotic prophylaxis for patients at high risk for subsequent infection: contaminated puncture wounds (especially with organic matter), diabetes mellitus, immunodeficiency, a retained organic foreign body, or injuries through an intact shoe. All patients with puncture wounds should be followed closely for evidence of infection, regardless of whether or not they receive prophylactic antibiotics. Prophylaxis regimes: First line: Flucloxacillin 500mg QDS PO (for patients >80kg use 1g QDS PO) Penicillin allergy: Clarithromycin 500mg BD for 3 days Contamination with organic matter e.g. soil: Co-amoxiclav 625mg TDS Duration of Prophylaxis: Antibiotic prophylaxis should not be prescribed for longer than 72 hours. Tetanus immunisation: Check the patient s tetanus immunization status and administer a booster dose of tetanus vaccine if needed. Page 12 of 16
Treatment of Septic Bursitis: Treatment of septic bursitis requires appropriate antibiotics, optimally guided by identification of the organism and antibiotic sensitivity testing. Draining of the infected bursa fluid is also indicated in the management of infected bursae. Initial antibiotic selection is guided by knowledge of common pathogens. In 80% of cases this is Staphylococcus aureus or other Grampositive organisms. Rationalisation of therapy should be conducted if cultures and sensitivities indicate an atypical pathogen. Treatment choice: Mild inflammation: Flucloxacillin 500mg qds PO (for patients >80kg use 1g qds PO) If penicillin allergic, clarithromycin 500mg bd PO If MRSA is suspected: doxycycline 100mg bd PO Typical duration: 14 days Moderate/Severe inflammation: Flucloxacillin 1g qds IV (for patients >80kg use 2g qds IV) If penicillin allergic or MRSA is suspected: Vancomycin IV. Treatment of Peritoneal Dialysis Exit Site Infections: Purulent drainage from the catheter exit site indicates the presence of infection. Erythema may or may not represent infection. An exit site infection is defined by the presence of purulent drainage, with or without erythema of the skin at the catheter-epidermal interface. Pericatheter erythema without purulent drainage is sometimes an early indication of an infection. In recently inserted catheters or following trauma, erythema may represent a skin reaction. Clinical judgement must be exercised to decide where antibiotic therapy should be commenced. Note, a positive culture on routine screening indicates colonisation rather than infection. Eradication of MSSA or MRSA using mupirocin nasal ointment in combination with enhanced exit site antiseptic cleaning is required. Patients presenting with discharge from the exit site and possible exit site infection should have the exit site swabbed and sent to microbiology for culture and sensitivity. Sensitivities should be reported in 48-72 hours. Most exit site infections are due to Gram positive (e.g. S. aureus) bacteria. Gram negative infections (e.g. P. aeruginosa, E. coli) are less common. Tunnel infections usually present as erythema, oedema or intense tenderness over the subcutaneous pathway. In the majority of cases this will be concurrent with an exit site infection. Staphylococcus aureus and Pseudomonas aeruginosa exit site infections in particular are often associated with tunnel infections. Page 13 of 16
Initial treatment should be given to cover Staphylococcus aureus: [If the patient has a history of Pseudomonas aeruginosa infections therapy should be given to cover this pathogen in addition]. Flucloxacillin 500mg qds PO (for patients >80kg use 1g qds PO) If penicillin allergic, clarithromycin 500mg bd PO Treatment should be reviewed weekly and continued for 14-28 days (until signs of infection have resolved and the exit site appears normal) Patients with signs of systemic illness (SIRS criteria present) and patients with cellulitis extending more than 2cm from the catheter exit site will require individualisation of antibiotic therapy and should be discussed with a senior renal physician and a microbiologist. Antimicrobial therapy must be reviewed when cultures & sensitivity results are available: Add rifampicin 300mg bd if rifampicin-susceptible S. aureus is isolated. Pseudomonas aeruginosa infections are especially difficult to treat and may require prolonged therapy with 2 antibiotics following discussion with a microbiologist. First line treatment is ciprofloxacin 250-500mg bd for 21 days. Ciprofloxacin should be given at 10am and 10pm to avoid concomitant administration with phosphate binders. Ciprofloxacin doses should be separated from binders by a minimum of 2 hours. For resistant organisms or non-responding infections, seek advice from a consultant nephrologist and a microbiologist: Consideration may need to be given to IV antimicrobial therapy Removal of PD catheter Antibiotic therapy should be continued until the exit site appears entirely normal minimum of two weeks for S. aureus and three weeks for P. aeruginosa. Early catheter removal and replacement should be considered for P.aeruginosa or tunnel infections. Renal Community Team The renal community team must be informed of all patients with exit site infections on diagnosis. Follow up will be determined by the patient s location. Page 14 of 16
Standards Indication should be documented. The rationale for any deviation from the Trust s Antibiotic Policy should be documented in a separate clinical note. Review the patient s allergy status prior to prescribing antibiotics. The initial prescription for antibiotics should have the total intended course length from the outset. Prescriptions for IV antibiotics should have be reviewed every 24hrs for suitability to switch to oral antibiotics Relevant culture results should be used to guide treatment where applicable. Patients should be reviewed for VSL#3 sachets in line with Trust policy. Explanation of terms & Definitions N/A References and Supporting Documents Li Philip Kam-Tao et al Peritoneal Dialysis-Related Infections Recommendations: 2010 Update Peritoneal Dialysis International 2010 vol 30 pp393-423 Clinical Resource Efficiency Support Team. 2005. Guidelines on the Management of Cellulitis in adults. Belfast: CREST Infectious Disease Society of America. 2005. Practice Guidelines for the Diagnosis and Management of Skin and Soft-Tissue Infections. Clinical Infectious Diseases; 41:1373 406 Medeiros IM, Saconato H. Antibiotic prophylaxis for mammalian bites. Cochrane Database of Systematic Reviews, 2001; Issue 2. Art. No.: CD001738. DOI: 10.1002/14651858.CD001738. Brakenbury PH, Muwanga C. A comparative double blind study of amoxycillin/clavulanate vs placebo in the prevention of infection after animal bites. Arch Emerg Med., 1989; 6(4): 251. Morgan M, Palmer J. Dog bites. BMJ, 2007; 334 (7590): 413. Dennis L. Stevens, Alan L. Bisno, Henry F. Chambers, E. Patchen Dellinger, Ellie J. C. Goldstein, Sherwood L. Gorbach, Jan V. Hirschmann, Sheldon L. Kaplan, Jose G. Montoya, James C. Wade; Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update Page 15 of 16
by the Infectious Diseases Society of America. Clin Infect Dis 2014; 59 (2): e10-e52. doi: 10.1093/cid/ciu296 Daniel J Sexton, Dlinor L Baron.H Soft tissue infections due to dog and cat bites. UpToDate. [online] Available: https://www.uptodate.com/contents/softtissue-infections-due-to-dog-and-cat bites?source=see_link§ionname=prophylaxis&anchor=h8 Chudnofsky CR, Sebastian S. Special wounds. Nail bed, plantar puncture, and cartilage. Emerg Med Clin North Am., 1992; 10(4): 801-22. Larry M Baddour, Aaron MP Ed: Daniel J Sexton, MD Allyson Bloom, MD Infectious complications of puncture wounds. UpToDate. [Online] Available: https://www.uptodate.com/contents/infectious-complications-of-puncturewounds?source=machinelearning&search=puncture%20wounds&selectedtitl e=1~118§ionrank=1&anchor=h505135224#h505135224 Fisher MC, Goldsmith JF, Gilligan PH. Sneakers as a source of Pseudomonas aeruginosa in children with osteomyelitis following puncture wounds. J Pediatrics. 1985; 106(4):607. NICE CKS Lacerations July 2015 NICE CKS (online) Available: https://cks.nice.org.uk/lacerations#!management Roles and responsibilities All clinical staff involved in the prescribing of antimicrobials to adhere to this policy including full documentation on EPMAR as detailed. Page 16 of 16