Nail’s involvement is NOT a feature of: March 2003
**Core Concept**
Involvement of the nails can be a manifestation of systemic diseases or conditions, but it is not a characteristic feature of all dermatological or systemic disorders. Nail changes can be seen in conditions such as psoriasis, lichen planus, and systemic lupus erythematosus.
**Why the Correct Answer is Right**
The correct answer is related to a condition where nail involvement is not typically observed. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that primarily affects the skin, joints, kidneys, and other organs. Nail changes are not a common feature of SLE, although they can occur in some cases.
**Why Each Wrong Option is Incorrect**
**Option A:** Psoriasis is a chronic skin condition characterized by scaling, erythema, and nail changes. Nail involvement in psoriasis is common, with features such as pitting, onycholysis, and subungual hyperkeratosis. Therefore, option A is incorrect because nail involvement is a feature of psoriasis.
**Option B:** Lichen planus is an inflammatory condition that affects the skin, mucous membranes, and nails. Nail changes in lichen planus can include thinning, brittleness, and scarring. Thus, option B is incorrect because nail involvement is a characteristic of lichen planus.
**Option C:** This option is blank, so we cannot evaluate it yet.
**Clinical Pearl / High-Yield Fact**
Nail changes can be a subtle but important clue to systemic disease, and a thorough examination of the nails should be included in the evaluation of patients with suspected systemic illness.
**Correct Answer:** C