Comma hairs: a dermatoscopic marker for tinea capitis: a rapid diagnostic method.

Area of Science:

• Dermatology
• Dermatopathology
• Mycology

Background:

• Dermatoscopy and videodermatoscopy are established tools for diagnosing skin conditions.
• Differentiating tinea capitis (TC) from alopecia areata (AA) can be challenging.
• Videodermatoscopy offers potential for improved diagnostic accuracy.

Purpose of the Study:

• To identify characteristic videodermatoscopy features of tinea capitis (TC).
• To assess the utility of videodermatoscopy in differentiating TC from alopecia areata (AA).

Main Methods:

• Videodermatoscopic examination of two patients with Microsporum canis-induced TC.
• Comparison of TC videodermatoscopy findings with those from 12 patients with alopecia areata (AA).
• Mycological culture and Wood lamp examination confirmed TC diagnosis.

Main Results:

• Comma hairs (comma-like structures) were the most prominent videodermatoscopy feature in TC.
• Broken and dystrophic hairs were also observed in TC.
• Alopecia areata (AA) showed exclamation mark hairs, vellus hairs, dystrophic/cadaverized hairs, and yellow dots.

Conclusions:

• Comma hairs are a distinctive videodermatoscopy marker for Microsporum canis-induced tinea capitis.
• This feature was absent in alopecia areata, which is typically characterized by exclamation mark hairs.
• Videodermatoscopy can aid in distinguishing fungal infections from autoimmune hair loss.