Understanding Kerion Celsi in Children: Diagnosis and Therapeutic Guidelines Through an Algorithm

Area of Science:

• Dermatology
• Mycology
• Pediatrics

Background:

• Kerion celsi (KC) is the inflammatory form of tinea capitis (TC), a common pediatric dermatophytosis.
• It represents 4%-10% of dermatophytoses in Mexico, frequently caused by *Microsporum canis* and *Trichophyton mentagrophytes*.

Observation:

• A six-year-old male presented with clinical signs of KC.
• Initial direct examination and fungal cultures were negative for definitive diagnosis.
• Histopathology revealed fungal elements (spores and hyphae) within and around hair shafts.

Findings:

• Despite negative initial tests, trichoscopy suggested *Microsporum* spp. infection.
• Treatment with itraconazole was initiated based on clinical suspicion and trichoscopic findings.
• The patient responded well to the antifungal therapy.

Implications:

• This case underscores the importance of considering KC in pediatric scalp infections, even with non-diagnostic initial tests.
• Trichoscopy can aid in suspecting causative agents when conventional methods fail.
• A proposed diagnostic and therapeutic algorithm may improve management of Kerion celsi.