Wencel, MarieShaibani, AzizGoyal, Namita A.Dimachkie, Mazen M.Trivedi, JayaJohnson, Nicholas E.Gutmann, LaurieWicklund, Matthew P.Bandyopadhay, SankarGenge, Angela L.Freimer, Miriam L.Goyal, NeelamPestronk, AlanFlorence, JulaineKaram, ChaficRalph, Jeffrey W.Rasheed, ZinahHays, MelissaHopkins, SteveMozaffar, Tahseen2023-09-222023-09-222021-10-18Wencel M, Shaibani A, Goyal NA, et al. Investigating Late-Onset Pompe Prevalence in Neuromuscular Medicine Academic Practices: The IPaNeMA Study. Neurol Genet. 2021;7(6):e623. Published 2021 Oct 18. doi:10.1212/NXG.0000000000000623https://hdl.handle.net/1805/35718Background and objectives: We investigated the prevalence of late-onset Pompe disease (LOPD) in patients presenting to 13 academic, tertiary neuromuscular practices in the United States and Canada. Methods: All successive patients presenting with proximal muscle weakness or isolated hyperCKemia and/or neck muscle weakness to these 13 centers were invited to participate in the study. Whole blood was tested for acid alpha-glucosidase (GAA) assay through the fluorometric method, and all cases with enzyme levels of ≤10 pmoL/punch/h were reflexed to molecular testing for mutations in the GAA gene. Clinical and demographic information was abstracted from their clinical visit and, along with study data, entered into a purpose-built REDCap database, and analyzed at the University of California, Irvine. Results: GAA enzyme assay results were available on 906 of the 921 participants who consented for the study. LOPD was confirmed in 9 participants (1% prevalence). Another 9 (1%) were determined to have pseudodeficiency of GAA, whereas 19 (1.9%) were found to be heterozygous for a pathogenic GAA mutation (carriers). Of the definite LOPD participants, 8 (89%) were Caucasian and were heterozygous for the common leaky (IVS1) splice site mutation in the GAA gene (c -32-13T>G), with a second mutation that was previously confirmed to be pathogenic. Discussion: The prevalence of LOPD in undiagnosed patients meeting the criteria of proximal muscle weakness, high creatine kinase, and/or neck weakness in academic, tertiary neuromuscular practices in the United States and Canada is estimated to be 1%, with an equal prevalence rate of pseudodeficiency alleles.en-USAttribution-NonCommercial-NoDerivatives 4.0 InternationalLate-onset Pompe disease (LOPDMuscle weaknessAcid alpha-glucosidase (GAA)Creatine kinaseArticle