A 8 year old child has localized non cicatrial alopecia over scalp with itching and scales. The diagnosis is :
**Localized Non-Cicatricial Alopecia**
**Core Concept**
Localized non-cicatricial alopecia in an 8-year-old child with scalp itching and scales suggests a condition that affects the scalp's hair follicles, leading to hair loss. This condition is often associated with an inflammatory process.
**Why the Correct Answer is Right**
The diagnosis is most likely **Psoriasis**. Psoriasis is a chronic autoimmune skin condition characterized by the rapid growth of skin cells, leading to thick, scaly skin. In children, scalp psoriasis can cause localized hair loss, itching, and scales. The condition is caused by an abnormal immune response, which leads to the activation of T cells and the release of pro-inflammatory cytokines.
**Why Each Wrong Option is Incorrect**
* **Option A:** Tinea capitis is a fungal infection of the scalp, typically presenting with hair loss, itching, and black dots (hair shafts broken off at the scalp surface). However, it does not typically cause scales.
* **Option B:** Lichen planopilaris is a form of lichen planus that affects the scalp, leading to inflammation and hair loss. However, it is less common in children and often presents with a different clinical appearance.
* **Option C:** Alopecia areata is an autoimmune condition that causes patchy hair loss, but it typically does not cause itching or scales.
**Clinical Pearl / High-Yield Fact**
In children, scalp psoriasis can be challenging to diagnose, and a biopsy may be necessary to confirm the diagnosis. A key clinical correlation is the presence of thick, scaly skin and hair loss in the same area.
**Correct Answer:** A. Psoriasis.