What is the appropriate management for a furuncle (boil) on the cheek with associated swelling?

Management of Furuncle on the Cheek with Swelling

Incision and drainage is the primary treatment for a large furuncle on the cheek, with systemic antibiotics added only if fever, systemic signs of infection (SIRS), or extensive surrounding cellulitis are present. 1

Differential Diagnosis Considerations

When evaluating a furuncle on the cheek with swelling, distinguish between:

• Furuncle (boil): Deep hair follicle infection with localized abscess formation, typically caused by S. aureus, presenting as a tender, inflammatory nodule with overlying pustule 1
• Carbuncle: Coalescent infection involving multiple adjacent follicles with pus draining from multiple openings—less common on the face 1
• Cellulitis: Diffuse spreading infection with erythema, warmth, and edema but no fluctuance or pus collection—requires antibiotics as primary treatment, not drainage 2
• Inflamed epidermoid cyst: Contains cheesy keratinous material; inflammation occurs from cyst wall rupture rather than true infection 1

Primary Treatment Algorithm

Step 1: Assess Size and Severity

• Small furuncles: Apply moist heat to promote spontaneous drainage 1, 3
• Large furuncles: Perform incision and drainage with thorough evacuation of pus and probing to break up loculations 1, 2
• Cover the drained wound with a dry dressing—do not pack with gauze as this increases pain without improving outcomes 1, 3

Step 2: Determine Need for Antibiotics

Systemic antibiotics are NOT routinely needed after adequate drainage unless the following are present 1, 3:

• Temperature >38°C or <36°C
• Tachycardia >90 beats/minute
• Tachypnea >24 breaths/minute
• White blood cell count >12,000 or <4,000 cells/µL
• Extensive surrounding cellulitis
• Multiple lesions
• Markedly impaired host defenses (immunocompromised, diabetes)

Step 3: Antibiotic Selection When Indicated

Use MRSA-active antibiotics given high community prevalence 1, 3:

• Trimethoprim-sulfamethoxazole (SMX-TMP)
• Doxycycline
• Clindamycin

Culture the pus from carbuncles and abscesses to guide therapy, though treatment without culture is reasonable in typical cases 1

Critical Anatomic Consideration: Facial Location

A furuncle on the cheek warrants heightened vigilance because:

• Facial infections can potentially spread to cavernous sinus via valveless facial veins
• Lower threshold for systemic antibiotics if any signs of progression or systemic involvement
• Consider antibiotics even without full SIRS criteria if extensive facial swelling is present 1

Common Pitfalls to Avoid

• Do not treat with antibiotics alone without drainage—this will fail for true furuncles with abscess formation 2
• Do not perform incision and drainage on cellulitis—there is no pus to drain; cellulitis requires antibiotics as primary treatment 2
• Do not pack the wound after drainage—simple dry dressing is superior 1, 3
• Do not routinely culture inflamed epidermoid cysts—inflammation is typically a chemical reaction, not infection 1

Management of Recurrent Disease

If the patient has recurrent furuncles 1, 3:

• Culture early to identify causative organism
• Search for local anatomic causes (pilonidal cyst, hidradenitis suppurativa, foreign material)
• Consider 5-day decolonization regimen: intranasal mupirocin twice daily, daily chlorhexidine washes, daily decontamination of personal items (towels, sheets, clothes)
• Screen and treat household contacts if ongoing transmission suspected
• Evaluate for neutrophil disorders only if recurrences began in early childhood, not needed for adult-onset disease 1