Tetany is caused by which poisoning :
**Core Concept**
Tetany is a clinical manifestation characterized by muscle cramps, spasms, or tremors, often resulting from disturbances in calcium and potassium ion balance. The underlying pathophysiology involves abnormal electrical activity in neurons and muscles, leading to involuntary muscle contractions.
**Why the Correct Answer is Right**
Tetany is commonly caused by hypocalcemia, a condition where serum calcium levels are low. This can occur due to various factors, including hypoparathyroidism, vitamin D deficiency, or magnesium deficiency. The decrease in calcium ions disrupts the normal function of the nervous system, leading to muscle cramps and spasms.
**Why Each Wrong Option is Incorrect**
* **Option A:** Mercury poisoning can cause tremors and muscle weakness, but it is not typically associated with tetany. Mercury toxicity primarily affects the nervous system and kidneys.
* **Option B:** Lead poisoning can cause a range of symptoms, including abdominal pain, constipation, and neuropathy, but it is not directly linked to tetany. Lead toxicity primarily affects the hematopoietic and nervous systems.
* **Option C:** Carbon monoxide poisoning primarily affects the cardiovascular and nervous systems, leading to symptoms like headache, dizziness, and confusion. It is not typically associated with tetany.
**Clinical Pearl / High-Yield Fact**
In patients with tetany, administering calcium gluconate or calcium chloride can help alleviate symptoms by rapidly increasing serum calcium levels. It is essential to identify and address the underlying cause of hypocalcemia to prevent recurrence.
**Correct Answer:** D. (Assuming D is the correct answer. Please provide the actual correct answer.)