Favus is type of:
**Core Concept**
Favus, also known as crusted scrotal or elephantiasis of the scalp, is a chronic and severe form of fungal infection of the scalp. It is characterized by the formation of thick, crusty scabs and is caused by the growth of a specific type of fungus.
**Why the Correct Answer is Right**
Favus is a type of tinea capitis, which is a fungal infection of the scalp. The causative organism is usually Trichophyton schoenleinii, a dermatophyte that infects the hair shaft and surrounding tissue, leading to the formation of crusts and scabs. The infection progresses slowly and can lead to significant scarring and hair loss if left untreated.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Favus is not a type of eczema, although it can present with similar symptoms such as itching and crusting.
**Option B:** This option is incorrect because Favus is not a type of impetigo, which is a bacterial infection of the skin that presents with red sores and crusting.
**Option C:** This option is incorrect because Favus is not a type of psoriasis, which is a chronic autoimmune condition that presents with scaly, red patches on the skin.
**Clinical Pearl / High-Yield Fact**
Favus is also known as "crusted scrotal" due to its characteristic appearance, and it is often associated with poor hygiene and malnutrition.
**Correct Answer:** C. Tinea capitis