What are the best antibiotics for treating an infected pilonidal cyst?

Best Antibiotics for Infected Pilonidal Cyst

For infected pilonidal cysts, incision and drainage is the primary treatment, with antibiotics covering Staphylococcus aureus and enteric bacteria as adjunctive therapy. The recommended antibiotic regimen is dicloxacillin or cephalexin for mild infections, and clindamycin plus either trimethoprim-sulfamethoxazole or a fluoroquinolone for moderate to severe infections.

Initial Management

• Incision and drainage is the recommended primary treatment for inflamed pilonidal cysts and abscesses 1
• Systemic antibiotics should be added based on the presence or absence of systemic inflammatory response syndrome (SIRS) such as fever, tachypnea, tachycardia, or abnormal white blood cell count 1

Antibiotic Selection

Mild Infections (no SIRS)

• First-line options:
  • Dicloxacillin 500 mg orally four times daily 1, 2
  • Cephalexin 500 mg orally four times daily 1, 3

Moderate to Severe Infections (with SIRS or significant surrounding cellulitis)

• First-line options:
  • Clindamycin 300-450 mg orally three times daily plus trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily) 1, 4
  • For patients with penicillin allergy: Clindamycin plus ciprofloxacin 1

For Suspected MRSA Infections

• Consider MRSA coverage if the patient has risk factors such as:
  • Previous MRSA infection
  • Nasal colonization with MRSA
  • Injection drug use
  • Failed prior antibiotic therapy 1
• Recommended options:
  • Trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily) 1, 4
  • Clindamycin 300-450 mg three times daily (if local resistance rates are low) 1

Duration of Therapy

• 5-10 days of antibiotic therapy is typically sufficient for most infected pilonidal cysts 1
• Treatment should be extended if the infection has not improved within this time period 1

Special Considerations

• Aspiration of pilonidal abscesses followed by oral antibiotics (cephalexin plus metronidazole) has shown effectiveness in selected patients with success rates of 83% 5
• For recurrent pilonidal abscesses, culture the abscess and treat with antibiotics active against the isolated pathogen 1
• Patients with recurrent infections may benefit from a 5-day decolonization regimen with intranasal mupirocin and chlorhexidine washes 1

Follow-up Care

• Proper wound care after surgical intervention is essential to prevent recurrence 6
• Patients should be advised to maintain good local hygiene and hair removal in the affected area 7
• For recurrent infections, search for local causes such as persistent pilonidal cyst or foreign material 1

Cautions

• Beta-lactams generally have inferior efficacy and more adverse effects compared to other antimicrobials for skin infections 1
• Monitor for adverse effects of antibiotics, particularly with clindamycin (risk of C. difficile) and trimethoprim-sulfamethoxazole (risk of rash and other hypersensitivity reactions) 4
• Fluoroquinolones should be reserved for cases where other antibiotics cannot be used due to their propensity for collateral damage 1