Table 1. Diagnostic criteria for cerebrotendinous xanthomatosis (Sekijima et al. ⁹⁾ ) .

A. Symptoms 1. Tendon xanthoma 2. Progressive neurological dysfunction a or mental retardation 3. Juvenile cataract 4. Juvenile coronary artery disease 5. Chronic unexplained diarrhea 6. Juvenile osteoporosis 7. Prolonged neonatal cholestasis B. Biochemical finding Elevated serum cholestanol level C. Genetic testing Pathogenic mutation in CYP27A1 gene (homozygosity or compound heterozygosity) D. Differential diagnosis Increased serum cholestanol level due to following diseases should be excluded ・Familial hypercholesterolemia ・Sitosterolemia ・Obstructive biliary tract disease ・Hypothyroidism Diagnostic category Definite: At least one of symptom in A and B+C+D Probable: At least one of symptom in A and B+D Possible: At least one of symptom in A and B

^a Representative progressive neurological dysfunction includes cognitive dysfunction, cerebellar symptoms, pyramidal symptoms, extrapyramidal symptoms, seizure, peripheral neuropathy, and sensory disturbance attributed to spinal cord.