Cerebrotendinous Xanthomatosis, Blood Spot

Use

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder of bile acid synthesis resulting from the deficiency of the mitochondrial enzyme, sterol 27-hydrolase. It leads to increased storage of cholestenol and ketosterol bile acid precursors in tissues and deficiency of chenodeoxycholic acid. This test is crucial for evaluating patients suspected of CTX, as it measures elevated levels of bile acid precursors such as 7-alpha-hydroxy-4-cholesten-3-one (7a-C4) and 7-alpha,12-alpha-dihydroxycholest-4-en-3-one (7a12aC4) in dried blood spot specimens. Diagnosis and early treatment with chenodeoxycholic acid can improve clinical outcomes.