The uronic acid level in urine is elevated in –
**Core Concept**
The question is testing the student's knowledge of mucopolysaccharidoses, specifically the association between uronic acid levels in urine and certain storage disorders. Uronic acid is a component of glycosaminoglycans (GAGs), which are polysaccharides found in connective tissue.
**Why the Correct Answer is Right**
The correct answer is related to Hurler syndrome, a type of mucopolysaccharidosis (MPS) caused by a deficiency of the enzyme alpha-L-iduronidase. This enzyme is responsible for breaking down GAGs, specifically dermatan sulfate and heparan sulfate, which contain uronic acid. Accumulation of these GAGs leads to elevated levels of uronic acid in urine, a characteristic diagnostic feature of Hurler syndrome.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not relate to the accumulation of GAGs or the specific enzyme deficiency causing Hurler syndrome.
**Option B:** This option is incorrect because it is not a recognized mucopolysaccharidosis associated with elevated uronic acid levels in urine.
**Option C:** This option is incorrect because it is not related to the storage disorder causing the elevation of uronic acid in urine.
**Clinical Pearl / High-Yield Fact**
A key aspect of Hurler syndrome is the accumulation of GAGs in various tissues, leading to progressive clouding of the cornea and eventual blindness, as well as skeletal and cardiac abnormalities. Early diagnosis is crucial to manage the disease and prevent long-term complications.
**Correct Answer: D. Hurler syndrome**