Pediatric Hair Disorders: Tinea Capitis and Traction Alopecia

Overview / Definition Tinea capitis is a fungal infection of the scalp caused primarily by dermatophytes, leading to hair loss and scalp inflammation. Traction alopecia, on the other hand, is a type of hair loss caused by prolonged tension on the hair follicles, often due to hairstyles that pull on the hair. Epidemiology Tinea capitis is most prevalent in children aged 3 to 14 years, with a higher incidence in African American children. It is more common in males than females. Traction alopecia can affect individuals of all ages but is particularly observed in young girls and women who frequently wear tight hairstyles. Tinea capitis: Prevalence ranges from 3% to 10% in children. Traction alopecia: Common in girls aged 5-12 years with tight braids or ponytails. Pathophysiology / Mechanism The pathophysiology of tinea capitis involves the invasion of hair follicles and keratinized tissue by dermatophytes, leading to an inflammatory response. Common causative agents include Trichophyton tonsurans and Microsporum canis. In contrast, traction alopecia results from mechanical stress on the hair follicles, leading to inflammation, follicular miniaturization, and eventual hair loss. Clinical Presentation Pediatric patients with tinea capitis may present with: Scaly patches on the scalp with hair loss Black dot alopecia (broken hair shafts) Kerion (a painful, inflammatory mass) Pruritus or itching In contrast, children with traction alopecia may exhibit: Localized areas of hair loss, typically at the hairline or on the scalp. Thinning of hair around the temples or nape of the neck. Follicular scarring in chronic cases. Diagnosis / Workup Diagnosis of tinea capitis is primarily clinical but may require: Wood's lamp examination (for Microsporum canis) Fungal culture of scalp hair or skin scraping Direct microscopic examination (KOH prep) of hair samples Traction alopecia is usually diagnosed based on history and clinical examination. A biopsy may be necessary in atypical cases