Abstract Our subject presented at 11 months of age, following a varicella zoster infection, with acute on chronic liver disease and was found to have raised serum chitotriosidase. White cell enzyme analysis for Gaucher, Niemann Pick A, B and lysosomal acid lipase deficiency were normal. Niemann Pick type C (NPC) disease was considered as a provisional diagnosis and liver transplantation assessment deferred until recovery from varicella and results of mutational analysis of NPC gene were available. Liver biopsy at a later date showed findings suggestive of glycogen storage disease (GSD) type IV but he was too unstable for an urgent liver transplantation and sadly passed away at the age of 13 months. The classic hepatic subtype of glycogen storage disorder type IV (GSD IV) is a rare metabolic cause of early‐onset liver disease and raised chitotriosidase. There are very few reports of raised chito in GSD IV. Liver transplantation has a favourable outcome for the hepatic subtype of GSD IV and early diagnosis in our subject could have potentially altered the outcome.
