We describe a patient with cerebrotendinous xanthomatosis (CTX) who saw a Rheumatologist because of joint and muscle pain in the lower limbs. Clinical examination did not reveal any classic joint disease; however, tendon lesions and clumsy gait were noted. The patient presented with a swollen Achilles tendon bilaterally and a parapareto-spastic gait; Babinski sign was positive on the right side, and hyperreflexia of both lower limbs could be demonstrated. As bilateral cataracts were present, we have interpreted the aforementioned signs as CTX with spinal involvement; mean plasma cholesterol was increased, thus confirming the diagnosis. The primary biochemical abnormality of this disease is a defect in the synthesis of bile acids; therefore, chenodeoxycholic acid (CDCA) has been tried, and beneficial effects following CDCA treatment, especially in the early stages of CTX, have been reported in the literature. We report this case because of the severity and the rarity of this disease, and also because of its hereditary transmission. Our aim is to underline the need of a precocious diagnosis, in order to prevent a further progression of the disease; this therapeutic goal can now be achieved, thanks to the therapeutic regimens recently developed