Background: Pompe disease is a lysosomal glycogen storage disease (GSDII) characterized by deficiency of acid glucosidase, resulting in lysosomal glycogen accumulation in multiple tissues, with cardiac and skeletal muscles being the most seriously affected. It manifests itself as a spectrum in multiple age groups including infancy, childhood and adulthood.
Case Report: We present a case of infantile Pompe disease that was detected at a four month well visit in the presence of hypotonia and failure to thrive.
Conclusions: Pompe disease can be diagnosed clinically by plotting growth parameters and performing developmental screening accurately. Enzyme replacement is the only available medical treatment for Pompe disease. High index of suspicion is necessary in diagnosing Pompe disease.

Keywords: Failure to Thrive, hypotonia, Developmental delay