Cerebrotendinous xanthomatosis

Cerebrotendinous xanthomatosis is a rare autosomal recessive lipid-storage disease caused by mutations in the sterol 27-hydroxylase gene. The accumula tion of cholestanol in various tissues characterizes this disease. Diagnosi s is based on determination of urinary bile alcohols. Therapy with chenodeo xycholic acid may arrest the progression of the disease. A 55-year-old woma n presented with a slowly progressive paraparesia and two firm subcutaneous tumors over the Knees. Her medical history revealed difficulty in standing and walking since infancy; bilateral juvenile cataracts, and mental retard ation. Histopathologic examination of one subcutaneous tumor was consistent with tendinous xanthoma. Substantial elevation of urinary bile alcohols co nfirmed the diagnosis. Treatment with oral chenodeoxycholic acid was starte d, with only mild improvement of spasticity Recognition of tendon xanthomas in a young patient with neurologic symptoms or cataracts (or both) is cruc ial to start early treatment and to avoid irreversible neurologic sequelae.