Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive inborn lipid storage disorder due to various pathogenic mutations in the CYP27A1 gene. Although the symptoms begin commonly in infancy, CTX diagnosis is often delayed. In this study, we report 7 Turkish CTX patients who had a delayed diagnosis despite early clinical signs and belonged to 6 unrelated families.We have retrospectively evaluated clinical, laboratory, imaging, and genetic findings of CTX patients, which were collected from 2 centers specialized in movement disorders: the Department of Neurology, Faculty of Medicine, Istanbul University, and the Department of Neurology, Faculty of Medicine, Mersin University.All patients were diagnosed with CTX after neurological symptom development, and their mean age at diagnosis was 38.7 ± 9.6 years, despite a mean onset age of 12.4 ± 10.6 years. The mean follow-up period was 28 months (range: 3-60 months). The most common initial clinical abnormalities in our cohort were unexplained chronic diarrhea (42%), febrile convulsion (42%), juvenile cataract (85%), childhood depression and autism (14%), parkinsonism (14%), and intellectual disability (100%). The most prominent neurological findings were the pyramidal-cerebellar syndrome (85%) and extrapyramidal signs (42%). All patients were genetically confirmed. Serum cholestanol levels were elevated in all patients and decreased after chenodeoxycholic acid (CDCA) treatment in 6 patients.This cohort is the largest CTX case series in Turkey. All cases showed improvement in gastrointestinal symptoms as a response to CDCA treatment and stabilization on neurological symptoms, i.e., no further progression of neurological abnormalities were noted during this treatment. Therefore, early diagnosis and treatment is crucial in preventing clinical deterioration.
