Congenital neuromuscular variant of glycogen storage disease type IV presenting as hypertrophic cardiomyopathy

variants. Enzymatic testing demonstrated reduced GBE activity, and histopathological findings showed myocardial Periodic acid-Schiff-positive and diastase-resistant inclusions, confirming the diagnosis. Neurological symptoms developed later, increasing the suspicion of a metabolic disorder.This case represents a unique presentation of this variant of GSD IV, primarily manifesting with hypertrophic cardiomyopathy. It underscores the importance of considering metabolic disorders in infants with cardiomyopathy, even when neurological symptoms are initially absent.