Musculoskeletal& Skin

Common Culprit: S. aureus 

Outpatient Treatment (after drainage, if applicable):

• Located in the face, hand, or perineum or from communities in which ≥10 to 15 percent of S. aureus isolates are MRSA

  1. Clindamycin 30 to 40 mg/kg per day orally in 3 or 4 doses (maximum daily dose 1.8 g) for 5 days

  2. Doxycycline 2 to 4 mg/kg per day orally in 1 or 2 doses (maximum daily dose 200 mg) for 5 days

  3. Trimethoprim-sulfamethoxazole 8 to 12 mg/kg per day orally of TMP, 40 to 60 mg/kg per day of SMX (maximum daily dose 320 mg of TMP, 1.6 g of SMX) for 5 days

• Low prevalence of MRSA and abscess not on face, hand, or perineum

  1. Cephalexin 25 to 100 mg/kg per day orally in 3 or 4 doses (maximum daily dose 2 g) for 5 days

  2. Cefadroxil 30 mg/kg per day orally in 2 divided doses (maximum daily dose 2 g) for 5 days

  3. Cefuroxime 30 mg/kg per day orally in 2 doses (maximum daily dose 1 g) for 5 days

  4. Clindamycin 30 to 40 mg/kg per day orally in 3 or 4 doses (maximum daily dose 1.8 g) for 5 days

     • 2nd-line

  5. Trimethoprim/Sulfamethoxazole 8 to 12 mg/kg per day orally of TMP, 40 to 60 mg/kg per day of SMX (maximum daily dose 320 mg of TMP, 1.6 g of SMX) for 5 days

     • 2nd-line

  6. Doxycycline 2 to 4 mg/kg per day orally in 1 or 2 doses (maximum daily dose 200 mg) for 5 days

     • 2nd-line

Common Culprit: Cutibacterium acnes

Treatment:

1. Topical Clindamycin 1% gel, lotion, pledget, solution, foam once or twice daily

   • Mild acne

   • Use in conjunction with Benzoyl peroxide

2. Doxycycline 100mg twice daily for 3-4 months

   • More moderate to severe

Common Culprits: Trichophyton rubrum, T. mentagrophytes/interdigitale complex, and Epidermophyton floccosum

Treatment: 

1. Clotrimazole 1% twice a day for 4 weeks

2. Terbinafine 1% once or twice a day for 1-4 weeks

NOT NYSTATIN

Common Culprits: Staphylococcus aureus (MSSA and MRSA), Group B Streptococcus (Streptococcus agalactiae), Gram-negative bacilli, Neisseria gonorrhoeae, Kingella kingae, Group A Streptococcus (Streptococcus pyogenes), Streptococcus pneumoniae, Haemophilus influenzae type b (Hib), N. gonorrhoeae

Treatment: 

1. Either Cefazolin, Nafcillin, Oxacillin, Clindamycin or vancomycin AND additional coverage as clinically indicated

Common Culprit: Pasteurella multocida, Capnocytophaga, Staphylococcus aureus, group A Streptococcus

Treatment of animal or human bite:

1. Amoxicillin-clavulanate 7:1 formulation 25 to 45 mg amoxicillin/kg/day in divided doses every 12 hours (max 875/125 a dose); prophylaxis: 3 to 5 days, established infection: 5 to 14 days.

2. Combination therapy with agent with activity against Pasteurella multocida and Capnocytophaga PLUS a second agent to cover anaerobes 

Special Considerations:

• Mice and rat bites may necessitate penicillin or ceftriaxone to cover rat bite fever, which is caused by Spirillum minus, Streptobacillus moniliformis, and Streptobacillus notomytis

• Rabbit bites may need a fluroquinolone or doxycycline added to the patient’s antibiotic regimen to cover tularemia (caused by Francisella tularensis)

Common Culprit: Streptococci groups A, B, C, G, and F, S. aureus (less common)

Treatment (all treatment courses are 5 days):

• Risk factors for MRSA

  1. Clindamycin 30 to 40 mg/kg per day orally in 3 or 4 doses (maximum daily dose 1.8 g)

     • Preferred

  2. Amoxicillin 40 to 50 mg/kg per day orally in 3 doses (maximum daily dose 1.5 g) plus Trimethoprim/Sulfamethoxazole 8 to 12 mg/kg per day orally of TMP, 40 to 60 mg/kg per day of SMX (maximum daily dose 320 mg of TMP, 1.6 g of SMX) 

  3. Cephalexin 25 to 100 mg/kg per day orally in 3 or 4 doses (maximum daily dose 2 g) plus Trimethoprim/Sulfamethoxazole 8 to 12 mg/kg per day orally of TMP, 40 to 60 mg/kg per day of SMX (maximum daily dose 320 mg of TMP, 1.6 g of SMX) 

  4. Amoxicillin 40 to 50 mg/kg per day orally in 3 doses (maximum daily dose 1.5 g) plus doxycycline 2 to 4 mg/kg per day orally in 1 or 2 doses (maximum daily dose 200 mg)

  5. Cephalexin 25 to 100 mg/kg per day orally in 3 or 4 doses (maximum daily dose 2 g) plus doxycycline 2 to 4 mg/kg per day orally in 1 or 2 doses (maximum daily dose 200 mg)

• No risk factors for MRSA

  1. Cephalexin 25 to 100 mg/kg per day orally in 3 or 4 doses (maximum daily dose 2 g)

     • Preferred

  2. Cefadroxil 30 mg/kg per day orally in 2 divided doses (maximum daily dose 2 g) 

  3. Cefuroxime 30 mg/kg per day orally in 2 doses (maximum daily dose 1 g)

• Erysipelas

  1. Amoxicillin 40 to 50 mg/kg per day orally in 3 doses (maximum daily dose 1.5 g) 

  2. Penicillin V 25 to 75 mg/kg per day orally in 3 or 4 doses (maximum daily dose 2 g)

  3. Clindamycin 30 to 40 mg/kg per day orally in 3 or 4 doses (maximum daily dose 1.8 g)

     • 2nd-line, PCN allergy

Special Considerations: In pilonidal disease with cellulitis consider Cephalexin 5 to 100 mg/kg/day divided every 6 to 8 hours (maximum dose 500 mg/dose) PLUS metronidazole

Common Culprits: Staphylococcus aureus, Streptococcus pyogenes, Candida albicans

Treatment of Secondary Bacterial Infection:

1. Topical mupirocin applied twice a day for five to seven days

   • If the infection is localized and mild

Special Considerations: Assess for Candida superinfection

Common Culprit: S. aureus

Treatment: 

Limited Involvement:

1. Mupirocin topically three times daily for 5 days

   • Limited involvement

2. Retapamulin topically twice daily for 5 days

   • Limited involvement

Extensive involvement, 7 day course:

1. Cephalexin 25 to 50 mg/kg per day in 3 to 4 divided doses (max dose 250 to 500 mg)

2. Dicloxacillin 25 to 50 mg/kg per day in 4 divided doses (max dose 250 to 500 mg)

3. Erythromycin (base) 40 mg/kg per day in 3 to 4 divided doses (max 250 mg 4 times per day)

   • PCN and cephalosporin hypersensitivity

4. Clarithromycin 15 mg/kg per day in 2 divided doses (max 250 mg twice per day)

   • PCN and cephalosporin hypersensitivity

Common Culprits: T. rubrum. Other frequent causes include E. floccosum, T. mentagrophytes/interdigitale complex, and T. indotineae

Treatment: 

1. Clotrimazole 1% once or twice a day for 1-3 weeks

2. Terbinafine 1% once or twice a day for 1-3 weeks

Extensive disease or if failing topical tx:

1. Terbinafine 10 to <20 kg: Oral: 62.5 mg once daily, 20 to 40 kg: Oral: 125 mg once daily, >40 kg: Oral: 250 mg once daily for 1-2 weeks 

Common Culprit: Borreliaceae

Treatment:

1. Doxycycline 4.4 mg/kg/day orally divided twice daily (maximum 100 mg per dose) for 10 days

2. Amoxicillin 50 mg/kg/day orally divided 3 times daily (maximum 500 mg per dose) for 14 days

3. Cefuroxime axetil 30 mg/kg/day orally divided twice daily (maximum 500 mg per dose) for 14 days

Common Culprits: Staphylococcus aureus (most common), Enterococcus, Streptococcus pyogenes (group A Streptococcus), anaerobic streptococci, Pseudomonas, Streptococcus agalactiae (group B Streptococcus), and Bacteroides species

Treatment:

1. Cephalexin 25 to 50 mg/kg per day orally in three or four doses (max2 g/day) for 7-10 days

2. Clindamycin 30 to 40 mg/kg per day orally in three or four doses (max 1.8 g/day) for 7-10 days

   • PCN allergy

Common Culprit: Staphylococcus aureus

Treatment:

1. Oxacillin IV 150 to 200 mg/kg/day divided every 4 to 6 hours; maximum daily dose: 12 g/day for 3-4 weeks

2. Cefazolin IV 100 to 150 mg/kg/day divided every 6 to 8 hours; usual adult dose: 2,000 mg/dose; maximum daily dose: 12 g/day for 21-28 days

3. Clindamycin IV or oral 30 to 40 mg/kg/day divided every 6 to 8 hours; maximum dose: IV: 900 mg/dose; Oral: 600 mg/dose for ≥3 to 4 weeks

The term "tinea corporis" refers to epidermal dermatophyte infections in sites other than the feet, groin, face, or hand.

Common Culprits: T. rubrum is the most common cause of tinea corporis. Other notable causes include Trichophyton tonsurans, Microsporum canis, T. mentagrophytes/interdigitale complex, T. indotineae, Microsporum gypseum, Trichophyton violaceum, and Microsporum audouinii

Treatment: 

1. Clotrimazole 1% once or twice a day for 1-3 weeks

2. Terbinafine 1% once or twice a day for 1-3 weeks

Extensive disease or if failing topical tx:

1. Terbinafine 10 to <20 kg: Oral: 62.5 mg once daily, 20 to 40 kg: Oral: 125 mg once daily, >40 kg: Oral: 250 mg once daily for 1-2 weeks 

Common Culprit: Rickettsia rickettsii

Treatment: 

1. Doxycycline 2.2 mg/kg/dose twice per day (maximum daily dose 200 mg) for ≤45 kg, 100 mg twice daily if >45 kg for 5 to 7 days; continue for at least 3 days after defervescence and clinical improvement observed

Special Considerations: Chloramphenicol is the only known alternative agent to doxycycline for the treatment of RMS. Doxycycline is preferred, if chloramphenicol must be given the dose is 50 mg/kg per day in four divided doses (maximum 4 grams per day).