Antibiotic Treatment for Infected Epidermal Inclusion Cysts
For infected epidermal inclusion cysts, incision and drainage is the primary treatment, with antibiotics only needed when there are signs of systemic infection, in which case an anti-staphylococcal agent such as dicloxacillin, cephalexin, clindamycin, or trimethoprim-sulfamethoxazole should be used. 1
Primary Management Approach
- Incision and drainage is the recommended first-line treatment for inflamed epidermal inclusion cysts 1
- Gram stain and culture of pus from inflamed epidermoid cysts are not recommended 1
- Most cases can be managed without antibiotics if there are no systemic signs of infection 1
When to Consider Antibiotics
Antibiotics should be considered as an adjunct to incision and drainage when:
- Patient shows signs of systemic inflammatory response syndrome (SIRS) 1:
- Temperature >38°C or <36°C
- Tachypnea >24 breaths per minute
- Tachycardia >90 beats per minute
- White blood cell count >12,000 or <400 cells/µL
- Patient has markedly impaired host defenses 1
- Infection extends beyond the cyst with significant surrounding cellulitis 1
Antibiotic Selection
When antibiotics are indicated, they should target Staphylococcus aureus as the most likely pathogen:
First-line options:
- Dicloxacillin or other penicillinase-resistant penicillins 1, 2
- Cephalexin or other first-generation cephalosporins 1
- Amoxicillin-clavulanic acid 1
For penicillin-allergic patients or suspected MRSA:
Special Considerations
- For severe infections with systemic illness, consider broader coverage until culture results are available 1
- In areas with high MRSA prevalence, empiric coverage should include MRSA-active agents 1
- Duration of therapy is typically 5-7 days, but may be extended based on clinical response 1
Common Pitfalls to Avoid
- Treating with antibiotics alone without performing incision and drainage 1
- Prescribing antibiotics for all infected cysts regardless of systemic symptoms 1
- Failing to consider MRSA coverage in areas with high prevalence 1
- Using first-generation cephalosporins in patients with immediate-type penicillin hypersensitivity 2
Remember that epidermal inclusion cysts are benign lesions that can occur anywhere in the body 3, 4, 5, 6, but the management principles remain consistent regardless of location. The primary treatment is incision and drainage, with antibiotics reserved for cases with systemic signs of infection or other high-risk features.