Moth eaten alopecia is seen in –
Moth-eaten alopecia refers to a pattern of hair loss that looks patchy with irregular, scattered areas of baldness. I remember that certain fungal infections can lead to this. Tinea capitis, which is a fungal infection of the scalp, often presents with this type of alopecia. The term "moth-eaten" comes from the way the infected hair breaks off at the scalp, leaving a scattered, patchy appearance.
Now, looking at the options (though they're not provided here), I need to think about other conditions that cause hair loss. Conditions like alopecia areata can cause patchy hair loss, but it's usually smooth and not moth-eaten. Androgenetic alopecia is more of a diffuse thinning. Conditions like lichen planopilaris might lead to scarring alopecia but not typically the moth-eaten pattern.
The key here is the association with fungal infections, specifically tinea capitis. The correct answer should be tinea capitis. The other options would be incorrect because they don't present with the same clinical features. The clinical pearl here is that fungal infections often have a distinct pattern of hair breakage, which is a telltale sign for tinea capitis.
**Core Concept**
Moth-eaten alopecia is a clinical descriptor for patchy, irregular hair loss with broken hair shafts, typically caused by **tinea capitis** (fungal infection of the scalp). It results from fungal invasion of hair follicles leading to hair shaft destruction and exclamation mark hairs.
**Why the Correct Answer is Right**
Tinea capitis, caused by dermatophytes like *Trichophyton* or *Microsporum*, infects hair follicles and shafts. The infection weakens the hair, causing it to break at the scalp surface, creating a "moth-eaten" appearance. Microscopy with potassium hydroxide (KOH) or fungal culture confirms diagnosis. This differs from alopecia areata (smooth, round patches) or scarring alopecia (permanent hair loss with follicular scarring).
**Why Each Wrong Option is Incorrect**
**Option A:** *Alopecia areata* presents with smooth, round patches, not broken hair.
**Option B:** *Androgenetic alopecia* causes diffuse thinning, not patchy, moth-eaten loss.
**Option C:** *Lichen planopilaris* leads to scarring alopecia with perifollicular erythema, not broken hair.
**Clinical Pearl / High-Yield Fact**
Moth-eaten alopecia is a **red flag for tinea capitis** in children. Always use Wood’s lamp or KOH prep to confirm fungal etiology before assuming an autoimmune cause. Remember: **fungus → broken hair; alopecia areata → smooth patches**.
**Correct Answer: C. Tinea capitis**