A 38-year-old woman from rural India presents with glossitis, angular cheilitis, and seborrheic dermatitis around the nasolabial folds. She reports a diet predominantly of polished rice and legumes. Regarding the B-vitamin deficiency states, all of the following are correctly matched with their cutaneous manifestations EXCEPT:

Explanation

## Identifying the Incorrect Statement **Key Point:** Thiamine (vitamin B₁) deficiency primarily manifests with neurological and cardiovascular symptoms (Wernicke–Korsakoff syndrome, beriberi), NOT dermatitis as a primary cutaneous sign. Dermatitis is not a characteristic feature of thiamine deficiency. ## B-Vitamin Deficiency: Cutaneous Manifestations | Vitamin | Deficiency State | Cutaneous Signs | Other Features | |---------|------------------|-----------------|----------------| | **B₁ (Thiamine)** | Beriberi, Wernicke–Korsakoff | None (neurological/cardiac) | Polyneuropathy, ataxia, ophthalmoplegia, heart failure | | **B₂ (Riboflavin)** | Ariboflavinosis | Cheilosis, angular cheilitis, glossitis, seborrheic dermatitis | Photophobia, corneal vascularization | | **B₃ (Niacin)** | Pellagra | Dermatitis (sun-exposed areas), hyperpigmentation | Diarrhea, dementia, death (4 Ds) | | **B₆ (Pyridoxine)** | Pyridoxine deficiency | Seborrheic dermatitis, glossitis, cheilitis | Peripheral neuropathy, seizures | **High-Yield:** The mnemonic **"4 Ds of Pellagra"** (Dermatitis, Diarrhea, Dementia, Death) is specific to niacin deficiency and is a NEET PG favourite. ## Clinical Pearl **Warning:** Do not confuse thiamine deficiency with other B-vitamins. Thiamine causes: - Wet beriberi → high-output cardiac failure, pulmonary edema - Dry beriberi → peripheral neuropathy, Wernicke–Korsakoff syndrome - **NO dermatitis** Riboflavin and pyridoxine both cause seborrheic dermatitis and glossitis, making them clinically similar in cutaneous presentation. [cite:Park 26e Ch 9]