SKIN AND SOFT TISSUE INFECTIONS Clinical Setting Empiric Therapy Duration Comments Minor Skin Infections Impetigo • Secondarily Mupirocin 2% topical ointment BID 7 days infected skin lesions such eczema, ulcers, or lacerations INCISION AND DRAINAGE (I&D) IS RECOMMENDED AS PRIMARY MANAGEMENT, AND ANTIBIOTICS ARE NOT INDICATED UNLESS PATIENT MEETS ONE OF THE Abscess, Furuncles, FOLLOWING CRITERIA: • Close clinical follow-up is and Carbuncles • Severe, extensive, rapidly recommended, especially in progressive cellulitis, or abscess >2 patients no receiving antibiotic Abscesses - cm therapy collections of pus • Signs or symptoms of systemic illness • Cultures and susceptibility are within the dermis • Elderly, immunosuppressed, active recommended when I&D is and deeper skin neoplasm or diabetes mellitus performed tissues • Circumstances where abscess is difficult to drain • Renal dose adjustment may be Furuncle - infection • Associated septic phlebitis required for vancomycin and of the hair follicle in • Inadequate response to I&D alone trimethoprim-sulfamethoxazole which purulent 5-7 days • Staphylococcus aureus resistance material extends EMPIRIC ORAL ANTIBIOTIC THERAPY FOR rates are lowest for TMP-SMX through the dermis OUTPATIENT THERAPY, OR ORAL STEP-DOWN (3%) and doxycycline (4%), into the THERAPY MEETING ABOVE CRITERIA: compared to clindamycin (43%). subcutaneous tissue, Preferred: where a small TMP-SMX* 1-2 DS tabs PO BID • Empiric therapy should target abscess forms MRSA until susceptibilities are Alternative: known, and then therapy should Carbuncle - Doxycycline 200 mg PO x1, then 100 be tailored. For patients with coalescence of mg PO BID MSSA, preferred oral step-down several furuncles therapy is cephalexin, TMP-SMX, into a single EMPIRIC IV ANTIBIOTIC THERAPY FOR or doxycycline if patient has inflammatory mass HOSPITALIZED PATIENTS: severe beta-lactam allergy Preferred: Vancomycin* IV (see nomogram, AUC goal 400-600) Clinical Setting Empiric Therapy Duration Comments EMPIRIC IV ANTIBIOTIC THERAPY FOR HOSPITALIZED PATIENTS: Preferred: Cefazolin*2 g IV q8h Alternative for patients with life- threatening penicillin allergy (in patients with or without risk for MRSA) Clindamycin 600 mg IV q8h Non-Purulent Cellulitis Alternative for patients at risk for MRSA non-purulent cellulitis: (Absence of purulent Vancomycin* IV (see nomogram, AUC drainage or exudate, goal 400-600) if MRSA coverage is • Blood cultures and cultures from ulceration, and no indicated 5 days for purulent SSTI are recommended associated abscess) patients with for patients with fever, rapidly Patients at risk for MRSA: rapid clinical progressive cellulitis, or signs of Empiric therapy for • Cellulitis worse on >48 hours of IV response. systemic illness β-hemolytic β-lactam therapy streptococcus is • Known MRSA colonization Longer duration • Adjust antimicrobial therapy recommended. • Prior history of MRSA infection of therapy is based on culture results • Recent intravenous drug use indicated if If there is a concern • Severe sepsis or septic shock infection has • Consider initial aggressive dosing for necrotizing not improved of antibiotics if severe sepsis or fasciitis, please see EMPIRIC ORAL ANTIBIOTIC THERAPY FOR morbidly obese patient treatment OUTPATIENT THERAPY, OR ORAL STEP-DOWN recommendations THERAPY: listed under that Preferred section Cephalexin* 500 mg PO QID or 1000 mg PO TID + TMP-SMZ* 1-2 DS BID to cephalexin, if patient presents with risk factors for MRSA (listed above) ALTERNATIVE FOR PATIENTS WITH LIFE- THREATENING PENICILLIN ALLERGY (IN PATIENTS WITH OR WITHOUT RISK FOR MRSA): Clindamycin 450 mg PO TID Page 2 of 10 Clinical Setting Empiric Therapy Duration Comments EMPIRIC IV ANTIBIOTIC THERAPY FOR • Blood cultures and cultures from HOSPITALIZED PATIENTS: purulent SSTI are recommended Preferred: for patients with fever, rapidly Purulent Cellulitis Vancomycin* IV (see nomogram, AUC progressive cellulitis, or signs of goal 400-600) systemic illness (Purulent drainage or exudate without Alternative for vancomycin, if 5-10 days • Staphylococcus aureus resistance a drainable abscess) documented allergy or intolerance: rates are lowest for TMP-SMX Linezolid** 600 mg IV/PO BID Longer duration (3%) and doxycycline (4%), Empiric therapy for of therapy is compared to clindamycin (43%). CA-MRSA is EMPIRIC ORAL ANTIBIOTIC THERAPY FOR indicated if recommended OUTPATIENT THERAPY, OR ORAL STEP-DOWN infection has • Empiric therapy should target THERAPY: not improved MRSA until susceptibilities are Therapy for β- Preferred: known, and then therapy should hemolytic TMP-SMX* 1-2 DS tabs PO BID be tailored. For patients with streptococci is likely MSSA, preferred oral step-down to be unnecessary Alternative: therapy is cephalexin, or TMP- Doxycycline 200 mg x1, then 100 mg SMX or doxycycline if patient has PO BID severe beta-lactam allergy Page 3 of 10 Clinical Setting Empiric Therapy Duration Comments PREFERRED: Piperacillin-tazobactam* 4.5 g IV q6h + Clindamycin 900 mg IV q8h + Vancomycin* (see nomogram, AUC • Emergent surgical and infectious goal 400-600) disease consultation is Necrotizing Fasciitis Optimal recommended duration is ALTERNATIVE FOR PATIENTS WITH PENICILLIN Early and aggressive unknown but ALLERGY: • Clindamycin is initiated for anti- surgical exploration should be Mild Allergy- Rash: toxin activity for Streptococcal and debridement is continued for a Cefepime* 2 g IV q8h and Staphylococcal infections, critical minimum of 2-3 + Clindamycin 900 mg IV q8h and could be discontinued after 1- days after + Vancomycin* (see nomogram, 3 days if infection has improved Emergent surgical completion of AUC goal 400-600) and patient is stable (assuming consultation is surgical another antibiotic with anti- recommended debridement Anaphylaxis: anaerobic activity is also Aztreonam* 2 g IV q8h administered). + Clindamycin 900 mg IV q8h + Vancomycin* (see nomogram, AUC goal 400-600) Page 4 of 10 Clinical Setting Empiric Therapy Duration Comments All systemic antimicrobial therapy should be used in combination with opening the incision and evacuation of infected material PREFERRED EMPIRIC INPATIENT THERAPY FOR Superficial Surgical SUPERFICIAL SSI, WITHOUT RISK FOR MRSA OR • Risk factors for MRSA include: Site Infections GNR (SEE BELOW): o nasal colonization Cefazolin* 2 g IV q8h o prior MRSA infection Infections involving OR o recent hospitalization the subcutaneous Cephalexin 500 mg PO QID or 1000 mg o recent antibiotics tissue within 30 days PO TID for mild-moderate infection, or of operation oral step-down therapy • Adjunctive systemic antimicrobial therapy is not routinely For SSI involving ALTERNATIVE EMPIRIC INPATIENT THERAPY FOR recommended unless associated deep tissue or organ PATIENTS WITH HIGH RISK OF MRSA OR with significant systemic response space or PCN/CEPHALOSPORIN ALLERGY: complicated by Vancomycin* IV (see nomogram, AUC • Indications for systemic sepsis/septic shock, goal 400-600) antimicrobials include: erythema 5 -7 days see below or organ and induration extending >5 cm specific guidelines EMPIRIC INPATIENT THERAPY FOR PATIENTS WITH Therapy may from wound edge, fever >38.5°C, (Intra-abdominal, HIGH RISK OF MRSA AND VANCOMYCIN ALLERGY need to be HR >110 beats/minute, WBC (NOT VANCOMYCIN INFUSION REACTION): Gynecology, extended based >12,000 Linezolid** 600 mg IV/PO q12h Meningitis, on severity of OR • Antibiotics should be adjusted Endocarditis, Bone infection and TMP-SMX* 1-2 DS tabs PO BID for mild- based on Gram stain, cultures and and Joint) response to moderate infection, or oral step-down sensitivities obtained from I&D treatment Suture removal plus therapy • Wound infection and systemic incision and EMPIRIC THERAPY FOR PATIENTS WITH SUPERFICIAL illness in the first 4 days drainage should be SSI FOLLOWING OPERATIONS OF THE AXILLA, (especially the first 48 hours) performed GASTROINTESTINAL TRACT, PERINEUM, OR FEMALE should prompt close wound If there is a concern GENITAL TRACT: examination for evidence of for necrotizing Cefazolin* 2 g IV q8h streptococcal or clostridial fasciitis, please refer + Metronidazole 500 mg PO/IV q8h necrotizing infection. See + Vancomycin* IV (see nomogram, AUC to that section necrotizing fasciitis section if goal 400-600), if risk for MRSA concern exists. OR Amoxicillin-clavulanate 875 mg PO BID • Consider initial aggressive dosing for mild-moderate infection, or oral of antibiotics in morbidly obese step-down therapy patient CEPHALOSPORIN/PCN ANAPHYLAXIS: Aztreonam* 2 g IV q8h + Metronidazole 500 mg PO/IV q8h + Vancomycin* IV (see nomogram, AUC goal 400-600) Page 5 of 10 Clinical Setting Empiric Therapy Duration Comments Deep tissue Surgical All systemic antimicrobial therapy should Site Infections or be used in combination with opening the any SSI complicated incision and evacuation of infected by sepsis/septic material shock EMPIRIC INPATIENT THERAPY FOR DEEP TISSUE SSI Infections involving OR COMPLICATED BY SEPSIS/SEPTIC SHOCK: the deep fascia or Piperacillin-tazobactam* 4.5 g IV q6h muscle within 30 7-10 days + Vancomycin* IV (see nomogram, AUC days of operation goal 400-600) Therapy may For SSI with organ need to be ALTERNATIVE WITH PCN ALLERGY WITHOUT space involvement, extended • Consider initial aggressive dosing of ANAPHYLAXIS, ANGIOEDEMA OR URTICARIA: see specific based on antibiotics if severe sepsis or Cefepime* 2 g IV q8h guidelines for Intra- severity of morbidly obese patient + Vancomycin* IV (see nomogram, AUC abdominal, goal 400-600) infection and Gynecologic, response to Meningitis,