What is the treatment for folliculitis versus a boil?

Treatment of Folliculitis vs Boil (Furuncle)

Key Distinction Between Folliculitis and Boils

Folliculitis is a superficial infection where inflammation and pus remain limited to the epidermis, while boils (furuncles) are deeper infections extending through the dermis into subcutaneous tissue with abscess formation. 1

• Folliculitis presents as small pustules or papulopustules (1mm-wide) at the hair follicle opening with superficial inflammation 2
• Boils (furuncles) appear as inflammatory nodules with overlying pustules through which hair emerges, representing deeper suppuration that extends into subcutaneous tissue 1
• Carbuncles are coalescent masses involving multiple adjacent follicles with pus draining from multiple follicular orifices, typically larger and deeper than furuncles 1

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Treatment Algorithm for Folliculitis

Mild, Localized Folliculitis

• Apply topical clindamycin 1% solution/gel twice daily for 12 weeks as first-line therapy 3, 4
• Alternative topical options include erythromycin 1% cream or metronidazole 0.75% 3
• Use gentle pH-neutral soaps with tepid water, pat skin dry, and wear loose-fitting cotton clothing to reduce friction 5, 3
• Avoid greasy creams and manipulation of the affected area 5, 3

Moderate to Severe or Widespread Folliculitis

• For inadequate response to topical therapy after 4-6 weeks, switch to oral tetracycline 500 mg twice daily for 4 months 3
• Alternatively, use doxycycline 100mg twice daily or minocycline 100mg twice daily for 2-4 weeks 5
• Avoid tetracyclines in children under 8 years of age 6
• For pregnant women or young children, use erythromycin or azithromycin 3

Refractory or Recurrent Folliculitis

• If no improvement after 8-12 weeks of oral tetracycline, use combination therapy with oral clindamycin 300 mg twice daily plus rifampicin 600 mg once daily for 10 weeks 3
• Obtain bacterial cultures for recurrent or treatment-resistant cases to guide antibiotic selection 5, 3
• Implement a 5-day decolonization regimen: intranasal mupirocin twice daily, daily chlorhexidine washes, and decontamination of personal items (towels, sheets, clothes) 1, 5
• For nasal colonization with S. aureus, apply mupirocin ointment twice daily in anterior nares for the first 5 days each month, which reduces recurrences by approximately 50% 6, 3

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Treatment Algorithm for Boils (Furuncles) and Carbuncles

Small Furuncles

• Apply warm, moist compresses several times daily to promote spontaneous drainage 6
• Moist heat brings the infection to a head and facilitates natural drainage, with cure rates of 85-90% with drainage alone 6
• Systemic antibiotics are usually unnecessary for uncomplicated small furuncles in otherwise healthy patients 1, 6

Large Furuncles and All Carbuncles

• Incision and drainage is the primary and most effective treatment 1, 3
• Perform incision, thorough evacuation of pus, and probe the cavity to break up loculations 3
• Simply cover the surgical site with a dry dressing (packing causes more pain without improving healing) 1
• Obtain Gram stain and culture of purulent material, though treatment without these studies is reasonable in typical cases 1

When to Add Antibiotics to Incision and Drainage

Add antibiotics active against S. aureus only when systemic inflammatory response syndrome (SIRS) is present or in patients with markedly impaired host defenses 1

SIRS criteria include: 1

• Temperature >38°C or <36°C
• Tachypnea >24 breaths per minute
• Tachycardia >90 beats per minute
• White blood cell count >12,000 or <4,000 cells/µL

Additional indications for antibiotics: 6

• Fever or signs of systemic infection
• Extensive surrounding cellulitis
• Multiple lesions
• Immunocompromised status

Antibiotic Selection for Boils Requiring Treatment

• For suspected or confirmed MRSA, use antibiotics with MRSA coverage such as trimethoprim-sulfamethoxazole, doxycycline, or clindamycin 3
• For children requiring antibiotics, use clindamycin 10-13 mg/kg/dose IV or PO every 6-8 hours if local clindamycin resistance is low (<10%) 6
• Treat for 5-10 days initially, extending if no improvement occurs 1, 3

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Management of Recurrent Abscesses

• Search for local causes such as pilonidal cyst, hidradenitis suppurativa, or foreign material 1
• Drain and culture recurrent abscesses early in the course of infection 1
• Treat with a 5- to 10-day course of an antibiotic active against the pathogen isolated 1
• Consider the same 5-day decolonization regimen as for folliculitis 1
• Evaluate for neutrophil disorders only if recurrent abscesses began in early childhood 1

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Common Pitfalls to Avoid

• Do not use needle aspiration for cutaneous abscesses - it is successful in only 25% of cases overall and <10% with MRSA infections 1
• Do not routinely cover for MRSA in typical folliculitis - MRSA is an unusual cause and routine coverage is unnecessary 3
• Do not continue topical treatments alone when they have already proven ineffective - escalate to systemic therapy 5
• Avoid topical steroids on infected areas as they may worsen the condition 5
• Do not neglect to culture recurrent or persistent lesions to identify resistant organisms 5
• Avoid prolonged use of topical steroids as they may cause skin atrophy 3