Antimicrobial Stewardship Program

Empiric therapy

Antibiotic therapy administered to a patient for suspected bacterial infection prior to the identification of etiology of infection. This is based on the most common organisms causing the suspected infection and the institution’s antibiogram.

Prophylactic Therapy

Antibiotics used to prevent an infection before it occurs as deemed necessary by national guidelines.

Definitive Therapy

Antibiotic therapy selected for bacterial infection based on antimicrobial susceptibility results.

De-escalation

Changing antibiotic therapy (narrower spectrum, reducing number of antibiotics, transitioning IV to oral, determining duration of therapy) based on cultures, susceptibilities, and clinical course. Typically occurs 24 to 48 hours after initiation of antibiotics.

• Obtain wound cultures for all admitted patients when feasible

• Empiric therapy for MRSA is recommended due to the high percentage of methicillin-resistant isolates at our institution.

• Many MRSA isolates are susceptible to clindamycin and trimethoprim/sulfamethoxazole (note: trimethoprim/sulfamethoxazole does not reliably treat Streptococcal infection).

• Once positive cultures return, transition to most narrow-spectrum agent (e.g., penicillin for Group A Streptococcus)

• Transition patients requiring initial IV therapy to PO therapy once improving

• Unstable patients or suspected necrotizing infections, consult ID service

Abscesses

1. Incision and Drainage (obtain culture)
2. Empiric antibiotics based on severity of presentation
   1. Mild with small lesion 1-2 cm (no systemic signs and symptoms¹): I&D only
   2. Moderate with larger lesion and/or fever: oral trimethoprim/sulfamethoxazole x 5 – 7 days
   3. Severe (failed oral antibiotics, systemic signs of infection¹, immunocompromised): vancomycin until appropriate response then consider oral therapy for total of 10 days

Cellulitis (default if unclear if cellulitis vs abscess)

• Empiric antibiotics
  • Clindamycin for mild infection
  • Vancomycin if penetrating trauma, purulent drainage, or systemic signs of infection¹
  • Consider additional coverage depending on exposure risks (e.g., traumatic wound associated with soil or water, call ID)
• Duration of therapy: 5-7 days, transition to PO when able (clindamycin alone, or TMP/SMX AND amoxicillin)

Bite Wounds

1. Empiric antibiotics directed towards both aerobic and anaerobic bacteria

• • Ampicillin-sulbactam, consider MRSA coverage (vancomycin or trimethoprim-sulfamethoxazole) for severe or worsening infections

2. Tetanus toxoid administration to patients without appropriate vaccination; consider rabies prophylaxis if animal bite

3. Duration of therapy: 7-10 days, transition to PO when able (amoxicillin/clavulanate alone, or with TMP/SMX if MRSA is suspected)

• High Risk – concern for joint involvement, face, eye, dental, labial, peri-rectal, concern for NEC, immunocompromised patient, major trauma, critically ill- consider ID Consult

• Empiric therapy for MRSA is recommended, due to the high percentage of methicillin-resistant isolates at our community.

• Many MRSA isolates are susceptible to clindamycin and trimethoprim/sulfamethoxazole.

Abscesses

1. Incision and Drainage (obtain culture)

2. Empiric antibiotics based on severity of presentation

   1. Mild with small lesion 1-2 cm (no systemic signs and symptoms¹): I&D only

   2. Moderate with larger lesion and/or fever: oral trimethoprim/sulfamethoxazole x 5 – 7 days

Cellulitis

1. Antibiotics – clindamycin for mild infection

2. Duration of therapy: 5-7 days

Bite Wounds

1. Antibiotics directed towards both aerobic and anaerobic bacteria

   1. amoxicillin-clavulanate

2. Tetanus toxoid administration to patients without appropriate vaccination

3. Duration of therapy: 7-10 days