Skeletal alterations, developmental delay and new mutations in juvenile-onset Pompe disease.

Pompe disease is an autosomal recessive disorder caused by a deficiency of acid α-glucosidase. In addition to the severe infantile form with cardiac involvement, late-onset variants can affect older children, adolescents (aged >1 year old) or adults. Patients with juvenile (a subgroup of late-onset type) Pompe disease typically do not have cardiac alterations e.g. hypertrophic cardiomyopathy, and the diagnosis is often difficult because it can clinically resemble myriad other neuromuscular disorders. A high level of clinical suspicion is necessary for a timely and accurate diagnosis. We describe 3 interesting cases of patients with juvenile-onset Pompe disease who presented some uncommon clinical features e.g. skeletal alterations and developmental delay, and describe a new genetic variant. Juvenile-onset Pompe disease may be accompanied by uncommon clinical signs that could delay the diagnosis of Pompe disease due to the global pictures resembling other metabolic disorders.