Reevaluating Muscle Biopsies in the Diagnosis of Pompe Disease: A Corroborative Report.

BACKGROUND Previous reports suggest that although a diagnostic muscle biopsy can confirm the presence of Pompe disease, the absence of a definitive biopsy result does not rule out the diagnosis. METHODS In this study, we reviewed patients with a limb-girdle syndrome who demonstrated nonspecific abnormalities of muscle, without evidence of the classical changes of acid maltase deficiency. These patients were rescreened for Pompe disease using dried blood spot (DBS) testing. RESULTS Twenty-seven patients provided blood samples for the DBS test. Four patients underwent subsequent genetic testing. Genetic analysis demonstrated that one patient tested positive for Pompe disease and one patient had one copy of a pathogenic variant. CONCLUSIONS In conclusion, the ability of a diagnostic muscle biopsy to definitively rule out the presence of Pompe disease is limited. There is a role for a screening DBS in all patients presenting with a limb-girdle syndrome without a clear diagnosis.