What is the possible infection in a patient with a tender right inguinal lymph node, recent pubic hair shaving, and multiple folliculitis or wounds with central dusky coloration near the inguinal region?

Clinical Diagnosis: Complicated Folliculitis with Progression to Furunculosis

This presentation is most consistent with bacterial folliculitis caused by Staphylococcus aureus that has progressed to furunculosis (deeper follicular abscesses), with reactive inguinal lymphadenopathy. The recent pubic hair shaving created microtrauma that allowed bacterial inoculation into hair follicles, and the progression from superficial folliculitis to multiple painful lesions with central dusky coloration indicates deeper infection extending into the subcutaneous tissue 1.

Key Diagnostic Features Supporting This Diagnosis

The central dusky coloration is particularly concerning and distinguishes furuncles from simple folliculitis. Furuncles are infections where suppuration extends through the dermis into subcutaneous tissue, forming small abscesses, unlike folliculitis where inflammation remains superficial with pus only in the epidermis 1. The clinical progression over 5 days from initial folliculitis to multiple deeper, more painful lesions with dusky centers is classic for this evolution 1.

The tender right inguinal lymph node represents regional lymphadenitis, which commonly occurs with skin infections in the drainage area 1. Enlarged painful nodes in the inguinal region following genital/pubic area infection strongly suggests bacterial etiology, particularly S. aureus 1.

Critical Warning Signs to Monitor

The dusky central coloration warrants close monitoring for potential progression to necrotizing infection. While this presentation most likely represents standard furunculosis, dusky or necrotic-appearing centers can occasionally herald more serious necrotizing soft tissue infections 1. Examine carefully for:

• Rapidly expanding erythema beyond the immediate lesion area
• Severe pain disproportionate to physical findings
• Systemic toxicity (fever, tachycardia, hypotension)
• Crepitus or bullae formation
• Skin that feels woody or indurated 1

Immediate Management Algorithm

For this patient with multiple lesions, tender lymphadenopathy, and severe pain, systemic antibiotics are indicated along with incision and drainage of larger lesions. 1, 2

Surgical Intervention

• Larger furuncles require incision and drainage - this is essential for source control 1
• Thoroughly evacuate pus and probe the cavity to break up loculations 1
• Cover with dry dressing (simplest and most effective approach) 1
• Gram stain and culture are indicated given multiple lesions and severity 1, 2

Antibiotic Therapy

Systemic antibiotics are necessary because this patient has multiple lesions, extensive surrounding symptoms, and lymphadenitis 1, 2. The presence of multiple lesions and regional lymphadenopathy represents one of the "unusual exceptions" where antibiotics are clearly indicated 1.

• First-line oral therapy: Doxycycline 100mg twice daily or minocycline 100mg twice daily for 2-4 weeks due to anti-inflammatory and antimicrobial effects 2
• Alternative if tetracyclines contraindicated: Clindamycin 150-300mg three times daily 2
• Consider MRSA coverage given the severity and if local resistance patterns warrant it 1

Topical Adjunctive Treatment

• Apply topical clindamycin 1% solution/gel twice daily to affected areas 2
• Warm compresses 3-4 times daily to promote drainage and reduce inflammation 2

Prevention of Recurrence

Given the clear precipitating factor of pubic hair shaving, prevention counseling is critical 2:

• Use proper lubrication when shaving and consider alternative hair removal methods 2
• Avoid manipulation of the skin to reduce secondary infection risk 2
• Use gentle pH-neutral soaps and tepid water for cleansing 2
• Wear loose-fitting cotton clothing to reduce friction and moisture 2

If recurrent episodes develop, implement decolonization protocol 1, 2:

• Intranasal mupirocin twice daily for 5 days each month (reduces recurrences by ~50%) 1, 2
• Daily chlorhexidine washes during active infection 2
• Decontamination of towels, sheets, and clothing 2

Common Pitfalls to Avoid

Do not rely on topical antibiotics alone for this presentation - the presence of multiple lesions, deep tissue involvement (furuncles), and lymphadenopathy mandates systemic therapy 1, 2. Simple folliculitis might respond to topical treatment, but this has clearly progressed beyond that stage 2.

Do not apply topical corticosteroids - while the inflammation may be tempting to treat with steroids, they will worsen bacterial infection 2.

Do not neglect surgical drainage - antibiotics alone are insufficient for established furuncles; the pus must be evacuated 1.