Is dermatophyte infection on the hair presenting with burning and pain rather than pruritus (itching) more common?

Dermatophyte Hair Infections Presenting with Pain and Burning

Painful, burning sensations in dermatophyte hair infections are most commonly associated with inflammatory variants of tinea capitis, particularly kerion, rather than the typical pruritic presentation. 1

Clinical Presentations of Tinea Capitis

Non-inflammatory Variants (Typically Pruritic)

• Grey patch: Caused by Microsporum species with fine scaling and patchy circular alopecia
• Black dot: Caused by Trichophyton species with fine scale and broken-off hair stubs
• Diffuse scale: Resembles dandruff with minimal alopecia

Inflammatory Variants (Often Painful/Burning)

• Kerion: A painful, boggy, inflammatory mass with associated alopecia

  • Presents as solitary or multiple plaques studded with pustules and matted with thick crust
  • Often accompanied by painful regional lymphadenopathy
  • Represents a delayed host inflammatory response to the dermatophyte
  • Commonly misdiagnosed as bacterial abscess 1

• Diffuse pustular: Patchy alopecia with scattered pustules or low-grade folliculitis

  • Associated with painful regional lymphadenopathy

Causative Organisms and Pain Correlation

• Kerion was traditionally associated with zoophilic, large-spore ectothrix species (T. mentagrophytes, T. verrucosum)
• In recent years, endothrix infections with T. tonsurans or T. violaceum have become more common causes of painful inflammatory presentations, particularly in urban areas 1
• Favus: A chronic inflammatory tinea capitis typically caused by T. schoenleinii
  • Characterized by yellow, crusted, cup-shaped lesions ("scutula")
  • Can result in cicatricial alopecia and may present with pain

Diagnostic Approach for Painful Dermatophyte Hair Infections

1. Clinical examination: Look for boggy, inflammatory masses with pustules and crusting

2. Sampling:

   • Pluck hairs from affected areas
   • Use blunt scalpel to remove hair and scalp scale
   • Consider scalp brushings or gauze swabs 1

3. Laboratory diagnosis:

   • Microscopy with 10-30% potassium hydroxide preparation
   • Culture on Sabouraud agar (with cycloheximide)
   • Dermoscopy may help visualize "comma-shaped" hairs in ectothrix infections or corkscrew hairs in Afro-Caribbean children 1

Clinical Pearls and Pitfalls

• Common pitfall: Misdiagnosing kerion as bacterial abscess, leading to inappropriate management
• Important consideration: Secondary bacterial infection can occur alongside the fungal infection
• Treatment note: A pruritic, papular "id" eruption (dermatophytid) may appear around the outer helix of the ear during treatment initiation - this represents a cell-mediated host response and should not be confused with a drug reaction 1
• Diagnostic challenge: The clinical signs of tinea capitis can be subtle, making diagnosis challenging, especially in inflammatory variants

Summary

While pruritus (itching) is the most common symptom in non-inflammatory tinea capitis, pain and burning sensations are hallmark symptoms of inflammatory variants, particularly kerion. The inflammatory response represents the host's delayed reaction to the dermatophyte infection, causing the painful, boggy masses characteristic of these presentations. Proper diagnosis through clinical examination and laboratory confirmation is essential to avoid misdiagnosis and ensure appropriate treatment.