Glycogen storage disease type IV (Andersen disease) is caused by a deficiency of the glycogen branching enzyme. We report a case in which liver biopsy played a key role in establishing the diagnosis. A 2-year-old girl presented to our hospital with hepatomegaly. Despite extensive testing, no definitive diagnosis was made, prompting a liver biopsy. The biopsy tissue revealed characteristic cytoplasmic inclusions. Genetic analysis identified a mutation in the GBE1 gene, confirming the diagnosis of glycogen storage disease type IV. Various special stains were helpful in characterizing the accumulated substances.
Ishikawa et al. (Mon,) studied this question.