What is the Difference Between Alopecia Areata and Tinea Capitis?

Alopecia areata and tinea capitis are two different causes of hair loss that can present as focal alopecia. The main differences between them are:

1. Appearance of the affected area: In alopecia areata, the lesion is round and smooth, while in tinea capitis, the skin can look slightly scaly and erythematous (red and inflamed).
2. Trichoscopic features: Trichoscopy is a non-invasive diagnostic method that allows the examination of hair and scalp. In tinea capitis, the most specific trichoscopic features are comma-shaped hairs, corkscrew hairs, and zigzag-shaped hairs. In alopecia areata, the most specific trichoscopic features are yellow dots, exclamation mark, and short vellus hairs.
3. Age and prevalence: Alopecia areata can occur at any age but is most common in children and young adults, with 30 to 48 percent of patients affected before 20 years of age. Tinea capitis, on the other hand, is more common in children and may also affect siblings at the same time.
4. Associated symptoms: Alopecia areata is not typically associated with itchiness, while tinea capitis may cause itching.

To differentiate between alopecia areata and tinea capitis, a scraping of the lesion can be performed to evaluate for fungi, which would indicate tinea capitis. Additionally, trichoscopy can be a useful method to differentiate between the two conditions.

Comparative Table: Alopecia Areata vs Tinea Capitis

Here is a table comparing the differences between Alopecia Areata and Tinea Capitis:

Alopecia Areata is an autoimmune disorder that causes unpredictable hair loss, while Tinea Capitis is a fungal infection that causes itchy, scaly, bald patches on the head. Both conditions cause non-scarring focal alopecia, with little inflammation or irritation. They can be diagnosed through physical examination and treated with medications like corticosteroids for Alopecia Areata and antifungal medications for Tinea Capitis.