A Middle aged man comes to OPD with paraesthesia of hands and feet, hyperkeratosis of palms, rain drop pigmentation and transverse line on nails. Most likely the person is having –
**Core Concept**
The patient's symptoms are characteristic of a neurodegenerative disorder affecting the peripheral nervous system, likely due to a deficiency of a specific nutrient essential for nerve function.
**Why the Correct Answer is Right**
The patient's symptoms, including paresthesia of hands and feet, hyperkeratosis of palms, raindrop pigmentation, and transverse lines on nails, are classic signs of a condition known as **Acid Maltase Deficiency (Pompe Disease)** is incorrect, but the correct diagnosis is **Acid Maltase Deficiency is not the answer, the correct answer is** **A.** **Pernicious Anemia is not the answer, the correct answer is** **A.** **Cobalamin deficiency**.
Cobalamin or Vitamin B12 deficiency leads to a megaloblastic anemia, and also affects the nervous system, causing paresthesia, neuropathy, and other neurological symptoms. The skin changes, such as hyperkeratosis of palms and raindrop pigmentation, are thought to be due to the accumulation of methylmalonic acid, a byproduct of fatty acid metabolism that is elevated in vitamin B12 deficiency.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while it is a cause of peripheral neuropathy, it does not account for the specific skin changes and nail abnormalities seen in this patient.
**Option B:** This option is incorrect because it is a cause of a different type of anemia and does not explain the patient's neurological symptoms.
**Option C:** This option is incorrect because while it is a cause of peripheral neuropathy, it does not account for the specific skin changes and nail abnormalities seen in this patient.
**Clinical Pearl / High-Yield Fact**
Vitamin B12 deficiency is often associated with a megaloblastic anemia, but it can also cause a range of neurological symptoms, including paresthesia, neuropathy, and cognitive impairment. The skin and nail changes seen in this patient are thought to be due to the accumulation of methylmalonic acid, a byproduct of fatty acid metabolism that is elevated in vitamin B12 deficiency.
**Correct Answer:** A.