OBJECTIVETo analyze a case of cerebrotendinous xanthomatosis (CTX) with mental retardation as the initial neurological symptom.

METHODSMedical imaging, histopathological assay and genetic testing were carried out to analyze the patient.

RESULTSNeurological manifestations of the 27-year-old male patient were initiated by mental retardation and subsequently memory lapses, ataxia, spastic paraplegia and fuzzy language. Other symptoms included cataract, xanthomatosis in Achilles tendon, kidney stones and high arches. The total bile acid in serum has risen to 14.7 umol/L. There were symmetrical abnormal signals in bilateral cerebellar dentate nuclei, hypointensities on T1WI and DWI and mixed signals on T2WI. Cholesterol crystallization and cholesterol granulomatous inflammation were found upon pathological examination of the Achilles tendon. The patient was found to have carried a compound heterozygous mutation of the CTX gene, which consisted of two novel mutations including c.379C>T (p.Arg127Trp) in exon 2 and c.1174G>A (p.Glu392Lys) in exon 6 of the CYP27A1 gene.

CONCLUSIONClinicians should be alert to cerebrotendinous xanthomatosis when the patient has mental retardation caused by genetic and metabolic factors beginning at a young age, particularly accompanied with tendinous xanthomatosis and cataracts. CTX can be readily diagnosed by histopathological assay and sequencing of the CYP27A1 gene.

Adult ; Cholestanetriol 26-Monooxygenase ; genetics ; Humans ; Intellectual Disability ; etiology ; Male ; Xanthomatosis, Cerebrotendinous ; complications ; genetics

Objective: Clinical manifestations, imaging findings, pathologic features, and genetic mutations of Chinese adult patients with cerebrotendinous xanthomatosis (CTX) were analyzed in order to achieve a greater understanding of CTX that can improve early detection, diagnosis, and treatment. Methods: Clinical data including medical history, neurologic and auxiliary examinations, imaging findings, and genetic profile were collected for an adult patient with CTX admitted to the Sixth Medical Center of Chinese People's Liberation Army General Hospital in August 2020. Additionally, a systematic review of genetically diagnosed Chinese adult CTX cases reported in major databases in China and other countries was performed and age of onset, first symptoms, common signs and symptoms, pathologic findings, imaging changes, and gene mutations were analyzed. Results: The proband was a 39-year-old female with extensive, early-onset nervous system manifestations including cognitive dysfunction and ataxia. Systemic lesions included juvenile cataract and a tendon mass. Cranial magnetic resonance imaging revealed cerebral atrophy, symmetric white matter changes predominantly in the pyramidal tract, and lesions in the cerebellar dentate nucleus. A novel homozygous mutation in the sterol-27-hydroxylase (CYP27A1) gene (c.1477-2A>C) was identified. There were no family members with similar clinical presentation although some were carriers of the c.1477-2A>C mutation. The patient showed a good response to deoxycholic acid treatment. Totally there were 56 cases of adult CTX patients in China, mostly in East China (31/56, 55.4%), at a male-to-female ratio of 1.8 to 1. Multiple organs and tissues including nervous system, tendon, lens, lung, and skeletal muscle were affected in these cases. The most common neurologic manifestations were cognitive dysfunction (44/52, 84.6%) and ataxia (44/51, 86.3%). The cases were characterized by early onset, chronic progressive damage of multiple systems, long disease course, and delayed diagnosis, making the disease difficult to manage clinically and resulting in poor prognosis. The 2 most common genetic mutations in Chinese adult CTX patients were c.1263+1G>A and c.379C>T. Exon 2 of the CYP27A1 gene was identified as a mutation hot spot. Conclusions: Chinese adult patients with CTX have complex clinical characteristics, a long diagnostic cycle, and various CYP27A1 gene mutations. Early diagnosis and intervention can improve the prognosis of these patients.
Humans ; Male ; Adult ; Female ; Xanthomatosis, Cerebrotendinous/pathology* ; Pedigree ; Cholestanetriol 26-Monooxygenase/genetics* ; Mutation ; Ataxia

Adult ; Aged ; China ; epidemiology ; Cholestanetriol 26-Monooxygenase ; genetics ; Cytochrome P450 Family 2 ; genetics ; Female ; Humans ; Male ; Middle Aged ; Polymorphism, Genetic ; Rural Population ; statistics & numerical data ; Vitamin D ; blood ; Vitamin D Deficiency ; epidemiology