Researchers published a case on the successful use of 5 years of alglucosidase alfa enzyme replacement therapy (ERT) in a woman who with late-onset Pompe disease (LOPD) who had been misdiagnosed for 3 decades.

The case report, published in Molecular Genetics and Metabolism Reports, reinforces other studies that suggest patients with slowly progressive limb-girdle and/or respiratory muscle weakness should be tested for Pompe disease with dried blood spot (DBS) screening.

“We report on our experience with an LOPD patient diagnosed after three decades of progressive symptoms,” the authors wrote. “She was treated with ERT (Myozyme) over five years with sustained ambulatory benefit to date.”

Continue Reading

The case involved a 57-year-old woman with a diagnosis of “probable polymyositis” since the age of 26 years. She had been treated with oral cyclophosphamide and prednisone for the previous year. Over the previous 15 years, she had seen 4 different neurologists and had had 2 muscle biopsies performed due to the lack of a clear diagnosis.

Read more about Pompe disease diagnosis

The fourth and final neurologist considered Pompe disease and DBS screening confirmed the diagnosis. Genetic testing further supported this conclusion.

Eighteen months after the diagnosis, the patient was started on alglucosidase alfa at 20 mg/kg and she has now been on the treatment for 5 years. Her condition gradually improved to the point where she can live independently with the help of a cane or walker and noninvasive ventilation at night.

The authors recommend increasing awareness among neurologists regarding the phenotypic presentation of Pompe disease. In particular, the presence of progressive limb-girdle type weakness should alert clinicians to the possibility of Pompe disease and could facilitate earlier diagnoses, which have been shown to be highly beneficial to patients.


Majaraj M, Skidmore D, Croul S, et al. Benefit of 5 years of enzyme replacement therapy in advanced late onset Pompe. A case report of misdiagnosis for three decades with acute respiratory failure at presentation. Mol Genet Metab Rep. Published online July 18, 2022. doi:10.1016/j.ymgmr.2022.100896