Question

Casal's necklace is a clinical sign associated with the deficiency of which vitamin?

• A. Cyanocobalamin
• B. Pyridoxine
• C. Riboflavin
• D. Niacin

Hint:

Casal’s necklace = Pellagra = Niacin (Vitamin B3) deficiency.

Answer 1

The Correct Option is D

Step 1: Understanding Casal's Necklace.
Casal's necklace is a hyperpigmented dermatitis seen around the neck in a necklace-like distributionIt typically occurs in sun-exposed areas and is a classical dermatological manifestation
Step 2: Association with Pellagra.
This sign is characteristic of PellagraPellagra occurs due to deficiency of Niacin (Vitamin B3) or its precursor tryptophanThe classical triad of pellagra is remembered as the 3 D’s — Dermatitis, Diarrhea, and Dementia
Step 3: Analysis of Options.
(A) Cyanocobalamin deficiency causes megaloblastic anemia and neurological symptoms
(B) Pyridoxine deficiency leads to neuropathy and sideroblastic anemia
(C) Riboflavin deficiency causes cheilosis and glossitis
(D) Niacin deficiency causes pellagra with Casal’s necklace
Step 4: Conclusion.
Therefore, Casal's necklace is associated with Niacin deficiency