Deficiency of sterol 27-hydroxylase leads to the reduced production of Chenodeoxycholic Acid, subsequently resulted in the upregulation of cholesterol 7α-hydroxylase (CYP7A1). More over, upregulation of this rate-limiting enzyme in the classic bile acid pathway results in the elevated level of 7α-Hydoxy-4-cholesten-3-one, an efficient precursor to cholestanol. There are no consensus data on the prevalence of CTX, the previous estimated incidence is 3-5/100,000 worldwide. 

Chenodeoxycholic Acid's main effect is to reduce the saturation of bile cholesterol. CTX could present at any age and its prevalence may be much higher than previously recognized. Bilateral Achilles tendon xanthomas, early-onset cataracts and neurological symptoms such as dementia and cerebellar ataxia are typical triad of CTX. Imaging studies have a significant role in prompt diagnosis. MRI and cerebellar magnetic resonance spectroscopic (MRS) imaging demonstrated abnormal structural/metabolic changes in brains of the CTX patients.Single photon emission computed tomography (SPECT) imaging of CTX cases showed presynaptic do pa minergic deficit associated with asymmetric parkinsonism symptom. However PET analysis of CTX is rarely reported. Several hundred of confirmed cases and 50 different mutations of the CYP27A1 gene have been reported worldwide Since Van Bogaert reported the first patient in 1937. In this study, we describe the clinical characteristics, pathology, whole body PET-CT neuroimaging and one novel mutation of the CYP27A1 gene in a Chinese family with CTX.

Gallstone mainly cholesterol stones or mixed stones consisting mainly of cholesterol, gallstones mainly seen in adults, especially for female, particularly maternal and taking birth control pills are common. Treatment: Small stones can be RONGSHI medicine RONGSHI as chenodeoxycholic acid, ursodeoxycholic acid, etc., and traditional Chinese medicine, others in vitro dissolution therapy gravel, stone or minimally invasive surgery reserved gallbladder, surgical removal of the gallbladder treatment.