Antimicrobial Use Guidelines (AMUG) version 21 - UW Health

LUNGS/PULMONARYCommunity-Acquired Pneumonia (CAP)Issue: Over-reliance on the use of moxifloxacin. Clinical experience using moxifloxacin for the treatment of anaerobicinfections and sensitive staphylococci is limited. The American Thoracic Society and Infectious Diseases Society offer achoice of a respiratory quinolone or a combination of cephalosporin and macrolide for the treatment of communityacquiredpneumonia. Moxifloxacin was chosen 70% of the time for CAP, and macrolide regimens only 25% of the time.Accumulating evidence suggests combination regimens containing a macrolide for CAP may be clinically superior. (ClinID 2003; 36: 389-95, 396-99) The recent Infectious Diseases Society of America Guidelines suggest de-emphasizing theuse of quinolones for CAP (Clinical Infectious Diseases 2003; 37:1405-33.) With the lowering of MICs forpneumococcal infections to penicillins and cephalosporins, virtually all respiratory infections can be treated withbeta-lactams.Suggestion: Restrict the use of quinolones for respiratory infections to community patients at risk for resistantpneumococci, beta-lactam failures, or patients with significant beta-lactam allergies. Consider using the combinationcephalosporin/macrolide choice for CAP more frequently. See UWHC hospital guidelines for the treatment of CAP locatedon uconnect.Hospital-Acquired PneumoniaIssues: Although Pseudomonas aeruginosa is an important cause of 30-35% of nosocomial pneumonias, empiric antipseudomonalregimens are often continued too long when the antimicrobial spectrum can be narrowed. Antimicrobialtherapy in general for nosocomial pneumonia is generally “too long.” MRSA serious pneumonias may require alternativeantimicrobial agents to vancomycin (Am Rev Resp Crit Care Med 2005:171:388-416 IDSA and ATS Guidelines for thetreatment of Healthcare Associated Pneumonia).Suggestion: Every effort should be made to obtain an adequate sputum specimen to guide antimicrobial therapy. WhenPseudomonas aeruginosa is NOT isolated from an adequate specimen, antimicrobial therapy should be adjustedaccordingly. The predictive value of a negative sputum gram stain for organisms is high, and this should prompt a searchfor alternative etiologies of pulmonary infiltrates and usually a discontinuation of antimicrobial therapy. Due to thepotential for bias by prior antibiotic use, the microbiology lab can be notified when a sputum sample is rejectedfor no bacteria seen and asked to implement the “exclude Pseudomonas and Staph protocol.” Also seecomments on double coverage of gram-negative pathogens in the bloodstream section.8 days of antimicrobial therapy is usually as good as 14 days (JAMA 2003:290:2588-98) under most clinicalcircumstances.Treatment of MRSA pneumonia with vancomycin may be suboptimal, and in consultation with the Infectious DiseaseService, therapy with linezolid may be considered (Chest 2003;124,1789-97 and 1632-34).CELLULITISIssue: Overuse of vancomycin and quinolones to treat susceptible staphylococci and streptococci.Suggestion: Unless there is a significant beta-lactam allergy, restrict the use of vancomycin and quinolones to otherindications. Use first-generation cephalosporins, nafcillin, or clindamycin in allergic patients. However, with the rise ofCA-MRSA, vancomycin may be needed as empiric therapy until more information is available.Issue: Continued use of antipseudomonal antimicrobials (and combination antimicrobial therapy) without culturedocumentedPseudomonas aeruginosa.Suggestion: Cellulitis is often a difficult condition for which to obtain microbiologic confirmation. Please weigh carefullywhether the patient is at risk for a Pseudomonas infection. Similarly, after the patient improves in the first 72 hours,continued double gram-negative coverage is rarely necessary.Also see Clinical Infectious Diseases 2005: 41: 1373-1406 IDSA guidelines for the treatment of skin and soft tissueinfections.