Cerebrotendinous xanthomatosis: a treatable hereditary neuro‐metabolic disease

Cerebrotendinous xanthomatosis is a rare autosomal recessive hereditary disease that is caused by a mutation in the gene encoding the mitochondrial enzyme sterol 27hydroxylase (CYP27). The CYP27 gene is located on chromosome 2q35-qter and is responsible for the conversion of cholesterol into cholic and chenodeoxycholic acid. Cerebrotendinous xanthomatosis results in increased levels of serum cholestanol, a cholesterol precursor, and increased deposition of cholestanol and cholesterol in various tissues, especially the lenses, tendons, and the central nervous system. The principal manifestations of Cerebrotendinous xanthomatosis include juvenile cataracts, tendon xanthomas, and progressive neurological symptoms. Early recognition of this condition is essential because cholic and chenodeoxycholic acid replacement therapy can prevent Cerebrotendinous xanthomatosis -induced brain damage, which leads to severe neurological dysfunction and death. We present the case of a patient with clinical, radiological, and biochemical evidence of Cerebrotendinous xanthomatosis and his response to cholic and chenodeoxycholic acid treatment.