title: Effect of enzyme replacement therapy on isokinetic strength for all major muscle groups in four patients with Pompe disease-a long-term follow-up.
abstract: Pompe disease is a rare, inherited metabolic myopathy characterized by progressive weakness of the proximal limb and respiratory muscles. We report the findings from four patients with late-onset Pompe disease treated with α-glucosidase (Myozyme) for 2 (n=2) and 6 (n=2) years, and monitored with isokinetic dynamometry, 6-minute walking test (6MWT), and vital capacity. Patients were evaluated after 6, 12, 24, 36, 48, 60, and 72months. In two patients, muscle size estimated by MRI and DXA scanning was also performed prior to and following 6months of treatment. After 2years of α-glucosidase treatment, maximal isokinetic muscle strength increased by 11% (0%-50%) [median (range)] and 6MWT improved by 18% (2%-40%). In the two patients treated for 6years, the increase in muscle strength stabilized at 40% and 6MWT stabilized at 32%. The improvements primarily occurred during the first 6months of treatment. Interestingly, the weakest muscle groups seemed to benefit more than those less affected, and greater improvements occurred for flexor muscles compared to extensor muscles. Vital capacity did not improve on treatment.
authors.affiliation: Clinical Neurology Research Group, Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, 8000 Aarhus C., Denmark; Institute of Clinical Medicine, Aarhus University, Brendstrupgårdsvej 100, 8200 Aarhus N., Denmark. Electronic address: christer.andreassen@ki.au.dk.
authors.forename: Christer Swan
authors.initials: CS
authors.lastname: Andreassen
authors.affiliation: Clinical Neurology Research Group, Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, 8000 Aarhus C., Denmark. Electronic address: jschlytter@gmail.com.
authors.forename: Jacob Mørup
authors.initials: JM
authors.lastname: Schlütter
authors.affiliation: Neuromuscular Research Unit, Department of Neurology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark. Electronic address: john.vissing@regionh.dk.
authors.forename: John
authors.initials: J
authors.lastname: Vissing
authors.affiliation: Clinical Neurology Research Group, Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, 8000 Aarhus C., Denmark. Electronic address: hennande@rm.dk.
authors.forename: Henning
authors.initials: H
authors.lastname: Andersen
mesh_terms: D000328:Adult; D056947:Enzyme Replacement Therapy; D005260:Female; D005500:Follow-Up Studies; D006009:Glycogen Storage Disease Type II / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000187:drug effects; D053580:Muscle Strength / Q000187:drug effects* / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D000520:alpha-Glucosidases / Q000627:therapeutic use*
chemical_list: C509951:GAA protein, human; D000520:alpha-Glucosidases
keywords: Enzyme replacement therapy; Late-onset Pompe disease; Muscle strength; Muscle volume; Respiratory function; Walking capacity