Commonest type of vitiligo –
First, I remember that vitiligo has different subtypes. The main types are generalized, segmental, and focal. Generalized vitiligo is the most common, affecting both sides of the body symmetrically. Segmental affects one side and is less common. Focal is rare and limited to a few areas. There's also acrofacial and mucosal types, but they might not be as common as generalized.
The question is asking for the commonest type. So the correct answer should be generalized vitiligo. The options given in the original question are A, B, C, D. Since the user didn't provide the options, I have to infer based on standard types. So the correct answer is generalized vitiligo.
Now, the core concept is the classification of vitiligo. The correct answer is generalized because it's the most prevalent form, usually symmetric, and involves multiple body areas. The other options like segmental or focal are less common. Clinical pearl would be to remember that generalized is the most common, and segmental is less so. I need to structure this into the required sections with the correct format.
**Core Concept**
Vitiligo is classified into generalized, segmental, focal, and other subtypes. The most prevalent form is determined by clinical patterns of depigmentation, with generalized vitiligo accounting for over 80% of cases due to its symmetric, widespread nature.
**Why the Correct Answer is Right**
Generalized vitiligo (Option C) involves symmetrical loss of pigment on both sides of the body, often starting at sites like hands, face, and genitalia. It is autoimmune-mediated, with T-cell destruction of melanocytes. Its high prevalence is due to systemic triggers (e.g., stress, genetic predisposition) and chronic, progressive course affecting multiple dermatomes.
**Why Each Wrong Option is Incorrect**
**Option A:** Segmental vitiligo affects only one side of the body and accounts for ~10% of cases, making it less common than generalized.
**Option B:** Focal vitiligo is localized to a single area, typically stable, and represents a minority of cases.
**Option D:** Acrofacial vitiligo, a subtype of generalized, is rare and characterized by depigmentation around nails and face.
**Clinical Pearl / High-Yield Fact**
Remember **G**eneralized > **S**egmental > **F**ocal > **A**crofacial in frequency. Generalized vitiligo is almost always bilateral, while segmental is unilateral and follows a dermatomal pattern.
**Correct Answer: C. Generalized vitiligo**