Clinical Improvement in a 12-Year-Old Girl with Pompe Disease Following Treatment with Avalglucosidase Alfa: A Case Report

초록

Introduction Pompe disease is a progressive metabolic disorder characterized by glycogen accumulation in muscle tissue, leading to severe muscle weakness, respiratory failure, and cardiomyopathy. This case reports the significant clinical improvement observed following the administration of avalglucosidase alfa to a 12-year-old girl with Pompe disease. Case Report The patient, who had a history of cleft lip and palate surgery, was admitted with fever and dyspnea and diagnosed pneumonia. Normal cognitive function was found, and her growth was below the 1st percentile. She had no significant difficulty walking but had been having difficulty with physical activities such as climbing stairs. She was admitted for 3 weeks. One month after discharge, she was readmitted with pneumonia and underwent trachemostomy due to repeated failed extubation. A neurological evaluation, including electromyography and brain imaging, was normal. Urinary organic acid tyrosine metabolites were increased, and plasma amino acid levels were normal. Alpha-D-glucosidase activity was decreased, and genetic testing revealed a pathogenic variant in the GAA gene (c.2173C > T, p.Arg725Trp; c.2189+1G > A in exon 15), confirming Pompe disease. The patient was started on alpha-glucosidase treatment every two weeks, but her clinical condition did not improve as expected after several doses. After her fourth dose, she developed pneumonia, and her six-minute walk test results worsened. Starting with her sixth dose, her treatment regimen was adjusted to a newly developed enzyme replacement therapy (ERT), avalglucosidase alfa. After her sixth dose, her frequency of respiratory infections decreased significantly, and she no longer required hospitalization for pneumonia. Seven months after the switch, she was able to remain without mechanical ventilation for more than 1 hour during the day. After nine months, the patient was minimally dependent on the ventilator during the day and only used the dev