Median chain acyl Co A dehydrogenase deficiency is characterised by all except
**Core Concept**
Median chain acyl CoA dehydrogenase (MCAD) deficiency is a rare genetic disorder caused by a deficiency of the enzyme medium-chain acyl-CoA dehydrogenase, which is crucial for the breakdown of medium-chain fatty acids during beta-oxidation. This deficiency leads to the accumulation of medium-chain acyl-CoA derivatives, causing a range of clinical manifestations.
**Why the Correct Answer is Right**
MCAD deficiency typically presents in infancy or early childhood, with symptoms including hypoketotic hypoglycemia, hepatomegaly, and sudden episodes of vomiting, lethargy, and even coma. The condition is often triggered by fasting, illness, or stress. The enzyme deficiency affects the breakdown of medium-chain fatty acids, leading to their accumulation and subsequent toxicity.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because MCAD deficiency is indeed characterized by hypoketotic hypoglycemia, which is a hallmark of the condition. Hypoketotic hypoglycemia occurs due to the impaired breakdown of fatty acids, leading to a decrease in ketone production and an increase in glucose utilization.
**Option B:** This option is incorrect because MCAD deficiency is often associated with hepatomegaly, which is a result of the accumulation of medium-chain acyl-CoA derivatives in the liver.
**Option C:** This option is incorrect because MCAD deficiency can indeed cause sudden episodes of vomiting, lethargy, and even coma, particularly during periods of fasting or illness.
**Clinical Pearl / High-Yield Fact**
A key clinical feature of MCAD deficiency is its association with sudden, unexplained episodes of illness, often triggered by fasting or stress. Recognizing this pattern is crucial for early diagnosis and treatment.
**Correct Answer: A**