Tinea capitis
📖 About
- Very common superficial fungal infection of the scalp.
- Primarily affects children, especially in communities with overcrowding and socio-economic deprivation.
🧬 Aetiology
- Caused by dermatophytes (fungi that invade keratinised tissues).
- Most common: Trichophyton tonsurans (anthropophilic).
- Occasionally: Microsporum canis (zoophilic, spread from cats/dogs 🐱🐶).
- Transmission: direct contact or via fomites (hats, combs, bedding).
🩺 Clinical Features
- Starts as a small papule at the base of a hair follicle → spreads to form a scaly circular plaque (“ringworm”).
- Within the lesion: brittle, broken “exclamation mark” hairs ✂️.
- Confluent patches of alopecia may develop, often itchy.
- Kerion: severe inflammatory reaction → boggy, tender, granulomatous mass studded with sterile pustules.
- Systemic signs may include fever 🌡️ and regional lymphadenopathy.
- Risk of permanent scarring alopecia if untreated.
🔍 Differentials
- Alopecia areata (smooth scalp, no scaling or inflammation).
- Psoriasis or seborrhoeic dermatitis of scalp.
- Bacterial folliculitis or impetigo.
- Discoid lupus erythematosus (scarring alopecia with scaling).
🧪 Investigations
- Wood’s lamp: Microsporum species fluoresce dull green.
- KOH preparation: shows fungal spores and hyphae.
- Culture on Sabouraud medium with antibiotics confirms the species.
💊 Management
- Systemic therapy is essential (topical agents alone are inadequate).
- First-line: Oral Griseofulvin for 6–12 weeks.
- Alternatives: Terbinafine, Fluconazole, or Itraconazole (useful in resistant cases).
- Adjunct: Selenium sulfide or ketoconazole shampoo twice weekly to reduce spore shedding and transmission.
- Public health: treat household contacts if symptomatic, avoid sharing combs, bedding, hats.
📚 References
🧾 Clinical Case Reports – Tinea Capitis
Case 1 – Inflammatory Type (Kerion) 🔥 A 7-year-old boy presents with a tender, boggy swelling on the scalp with
pustules, hair loss, and regional lymphadenopathy. Fungal culture grows Microsporum canis.
👉 Diagnosis: Tinea capitis – kerion.
👉 Management: oral griseofulvin + topical antifungal shampoo; monitor for scarring alopecia.
Case 2 – Non-Inflammatory Type 🌙
A 9-year-old girl is noted to have patchy hair loss with fine scaling but minimal erythema.
Woods lamp shows green fluorescence, and culture isolates Trichophyton tonsurans.
👉 Diagnosis: Tinea capitis – grey patch type.
👉 Management: oral terbinafine + antifungal shampoo for contacts.
