Published in:
Open Access
01-12-2019 | Niemann-Pick Disease | Research article
Oxysterol/chitotriosidase based selective screening for Niemann-Pick type C in infantile cholestasis syndrome patients
Authors:
Anna V. Degtyareva, Tatiana Y. Proshlyakova, Marina S. Gautier, Dmitry N. Degtyarev, Elena A. Kamenets, Galina V. Baydakova, Denis V. Rebrikov, Ekaterina Y. Zakharova
Published in:
BMC Medical Genetics
|
Issue 1/2019
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Abstract
Background
Niemann-Pick disease type C (NP-C) is an inherited neurodegenerative disease (1 per 100 000 newborns) caused by NPC proteins impairment that leads to unesterified cholesterol accumulation in late endosomal/lysosomal compartments. To date the NP-C diagnostics is usually based on cholesterol detection in fibroblasts using an invasive and time-consuming Filipin staining and we need more arguments to widely introduce oxysterols as a biomarkers in NP-C.
Methods
Insofar as NP-C represents about 8% of all infant cholestases, in this prospective observational study we tried to re-assess the specificity plasma oxysterol and chitotriosidase as a biochemical screening markers of NP-C in children with cholestasis syndrome of unknown origin. For 108 patients (aged from 2 weeks to 7 years) the levels of cholestane-3β,5α,6β-triol (C-triol) and chitotriosidase (ChT) were measured. For patients with elevated C-triol and/or ChT the NPC1 and NPC2 genes were Sanger-sequenced and 47 additional genes (from the custom liver damage panel) were NGS-sequenced.
Results
Increased C-triol level (> 50 ng/ml) was detected in 4 (of 108) infants with cholestasis syndrome of unknown origin, with following molecular genetic NP-C diagnosis for one patient. Plasma cholesterol significantly correlates with C-triol (p < 0.05). NGS of high C-triol infants identified three patients with mutations in JAG1 (Alagille syndrome) and ABCB11 (Byler disease) genes. Increased ChT activity was detected in 8 (of 108) patients with various aetiologies, including NP-C, Byler disease and biliary atresia.
Conclusion
Combined analysis of ChT activity and C-triol levels is an effective method for identifying NP-C.