CEREBROTENDINOUS XANTHOMATOSIS

CTX; Van Bogaert-Scherer-Epstein Disease; Xanthomatosis Cerebrotendinous; Cerebral Cholesterosis; Cerebrotendinous Cholesterinosis; Cholestanol Storage Disease; Cholestanolosis; Sterol 27-hydroxylase Deficiency

Cerebrotendinous Xanthomatosis (CTX) is an inherited lipid storage disorder where the body lacks the enzyme to break down different forms of cholesterol, leading to lipid accumulation in all tissues in the central nervous system, as well as in the tendons, skin, lungs, and bones. Xanthomas (fatty yellow nodules) in the tendons begin to form in early adulthood. People with CTX are also at an increased risk of developing cardiovascular disease.

Diagnostic testing: The diagnosis of CTX is established by:

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  Clinical examination;

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  Molecular genetic testing for the CYP27A1 gene;

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  Biochemical testing;

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  High cholesterol concentration;

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  Normal-to-low plasma cholesterol concentration;

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  Decreased chenodeoxycholic acid;

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  Increased concentration of bile alcohols and glyconjugates; and

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  Increased concentrations of colestanol and apolipoprotein B in cerebrospinal fluid.

Physical findings:

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  Cataracts;

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  Xanthomas in the Achilles tendon, patella, elbow, hand, and neck tendons;

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  Cognitive impairments;

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  Dementia;

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  Spasticity;

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  Ataxia; and

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  Peripheral neuropathy.

ICD-9: 272.2

Cataracts develop in childhood or adolescence, and xanthoma formation tends to develop in the second and third decades of life. Neurological impairments involving seizures, dementia, and involuntary reflexes and movement begin in the third decade of life and progress until death. The severity of CTX varies widely with the cause of death usually due to myocardial infarction and progressive mental deterioration.

There is no current cure for CTX. Treatment focuses on the management of disease symptoms. Cataract extraction is typically required in at least one eye by the age of 50 years. Seizures, spasticity, and parkinsonism are treated symptomatically.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Laboratory studies of CYP27A1 gene activity; and

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  Imaging studies such as an MRI or CT scan of the brain showing diffuse atrophy in the cerebellum, basal ganglia, and cerebrum.

Suggested Listings for Evaluation: