What type of folliculitis causes abscesses?

Types of Folliculitis That Cause Abscesses

Deep folliculitis, particularly furuncles and carbuncles caused by Staphylococcus aureus, are the main types of folliculitis that progress to form abscesses. 1

Deep Folliculitis Types That Form Abscesses

Furuncles (Boils)

• Infections of hair follicles caused primarily by S. aureus
• Suppuration extends through the dermis into subcutaneous tissue, forming a small abscess
• Clinically present as inflammatory nodules with overlying pustules through which hair emerges
• Differ from superficial folliculitis, where inflammation is limited to the epidermis 1

Carbuncles

• Form when infection involves several adjacent hair follicles
• Create a coalescent inflammatory mass with pus draining from multiple follicular orifices
• Typically larger and deeper than furuncles
• Most commonly develop on the back of the neck
• More likely to occur in individuals with diabetes 1

Folliculitis et Perifolliculitis Capitis Abscedens et Suffodiens

• Rare, severe form of deep folliculitis that forms extensive abscesses
• Characterized by fluctuating painful fistule-forming conglomerates of abscesses
• Often affects the occipital scalp
• Most common in men of African-American or African-Caribbean descent aged 20-40 years 2

Folliculitis Decalvans

• Rare inflammatory condition of the scalp
• Can progress to form painful pustules and abscesses
• Leads to scarring alopecia
• S. aureus is believed to play a role in its development 3

Pathophysiology of Abscess Formation

• In deep folliculitis, infection extends beyond the hair follicle into surrounding tissue
• Suppuration progresses through the dermis into subcutaneous tissue
• Neutrophilic infiltration is the initial histopathologic finding, followed by granulomatous infiltrate 2
• Abscess formation represents a collection of pus within the dermis and deeper skin tissues 1

Risk Factors for Abscess-Forming Folliculitis

• Diabetes mellitus (particularly for carbuncles)
• Impaired immune function, especially neutrophil dysfunction
• Poor circulation from peripheral vascular disease
• Hyperglycemia creating favorable conditions for bacterial growth
• Increased skin colonization with S. aureus 4
• Poor personal hygiene
• Close contact with infected individuals 1

Management of Folliculitis-Associated Abscesses

Treatment Approach

1. Incision and drainage is the primary treatment for large furuncles and all carbuncles 1
2. Probing the cavity to break up loculations may be necessary 4
3. Cover the surgical site with a dry dressing (avoid packing with gauze as it may cause more pain without improving healing) 1, 4
4. Systemic antibiotics are usually unnecessary unless there is:
   • Fever or other evidence of systemic infection
   • Extensive surrounding cellulitis
   • Markedly impaired host defenses
   • Presence of SIRS (temperature >38°C or <36°C, tachypnea >24 breaths/min, tachycardia >90 beats/min, or WBC >12,000 or <400 cells/μL) 1

For Recurrent Abscesses

• Search for local causes such as pilonidal cyst, hidradenitis suppurativa, or foreign material 1
• Drain and culture early in the course of infection 1
• Consider a 5-day decolonization regimen:
  • Intranasal mupirocin twice daily
  • Daily chlorhexidine washes
  • Daily decontamination of personal items (towels, sheets, clothes) 1, 4
• For persistent recurrent cases, consider clindamycin 150 mg daily for 3 months 4
• Evaluate for neutrophil disorders if recurrent abscesses began in early childhood 1, 4

Common Pitfalls and Caveats

• Needle aspiration of abscesses has low success rates (<25% overall, <10% with MRSA) and is not recommended 1
• Cultures are not routinely needed for typical cases but should be obtained for recurrent abscesses 1, 5
• Simple folliculitis is more superficial and does not typically form abscesses; don't confuse with deeper infections 1
• In diabetic patients, maintain optimal glycemic control to prevent recurrent skin infections 4
• Carbuncles require more aggressive management than furuncles due to their deeper and more extensive nature 1
• Consider MRSA coverage for patients with infections that have not improved with initial treatment 6