B35.6 Tinea cruris

Name of the Condition

• Tinea cruris
  
  • Common name(s): Jock itch

Summary

Tinea cruris is a fungal infection affecting the skin of the groin, inner thighs, and buttocks. It is characterized by an itchy, red rash that may spread to adjacent areas. The condition is caused by dermatophyte fungi and is more common in warm, moist environments.

Causes

Tinea cruris is caused by dermatophyte fungi, most commonly Trichophyton rubrum and Epidermophyton floccosum. These fungi thrive in warm, damp areas and invade the keratinized layers of the skin, leading to infection. Transmission often occurs through direct contact with infected individuals, contaminated clothing, or shared surfaces like towels.

Risk Factors

• Prolonged exposure to moisture (e.g., sweating, wet clothing)
• Tight or restrictive clothing
• Participation in activities with shared surfaces (e.g., locker rooms, swimming pools)
• Weakened immune system
• Close contact with infected individuals or animals

Symptoms

• Itchy, red rash in the groin, inner thighs, or buttocks
• Scaly, raised, or ring-like patches with clear skin in the center
• Burning or discomfort in affected areas
• Rash that may spread to the abdomen or thighs

Diagnosis

Diagnosis typically involves a physical examination of the affected area. A skin scraping for microscopic analysis (KOH test) or fungal culture may be performed to confirm the presence of dermatophytes. Clinical presentation is often sufficient for diagnosis in uncomplicated cases.

Treatment Options

• Topical antifungal creams or ointments for localized infections.
• Oral antifungal medications for severe, widespread, or recurrent cases.
• Keeping the affected area clean and dry to promote healing.

Prognosis and Follow-Up

With appropriate treatment, tinea cruris usually resolves within 2–4 weeks. Recurrence is common if preventive measures are not followed. Follow-up may be recommended to ensure complete resolution and to address any persistent symptoms.

Complications

• Secondary bacterial infections from scratching
• Spread of infection to other body areas (e.g., feet, hands)
• Chronic or recurrent infections in immunocompromised individuals

Lifestyle & Prevention

• Keep the groin area clean and dry, especially after exercise.
• Wear loose-fitting, breathable clothing.
• Avoid sharing personal items like towels or clothing.
• Use antifungal powders or sprays in high-risk environments (e.g., locker rooms).

When to Seek Professional Help

Seek medical attention if symptoms worsen, do not improve with over-the-counter treatments, or if there are signs of secondary infection (e.g., pus, increased pain, fever).

Tips for Medical Coders

Document the location (groin, inner thighs, buttocks) and clinical findings (e.g., rash, itching) to support the diagnosis. Ensure the code B35.6 is used for tinea cruris and not confused with other dermatophyte infections affecting different body areas.