title: Myotonia congenita and myoadenylate deaminase deficiency: case report.
abstract: Approximately 1-2% of the population has a deficiency of the enzyme myoadenylate deaminase. Early reports suggested that patients with myoadenylate deaminase deficiency had various forms of myalgia, and exercise intolerance. However, a deficiency of the enzyme has been described in many conditions, including myopathies, neuropathies, and motor neuron disease. We report a patient with clinical diagnosis of myotonia congenita and absent myoadenylate deaminase reaction on the muscle biopsy. This is the first description of myoadenilate deaminase deficiency with myotonia congenita. Myoadenylate deaminase deficiency is the most common enzymatic deficit of muscle, and the association with other neuromuscular diseases is coincidental.
authors.affiliation: Division of Neurology and Neuromuscular Disorders, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil. scola@hc.ufpr.br
authors.forename: Rosana Herminia
authors.initials: RH
authors.lastname: Scola
authors.forename: Fabio Massaiti
authors.initials: FM
authors.lastname: Iwamoto
authors.forename: Carlos Henrique
authors.initials: CH
authors.lastname: Camargo
authors.forename: Walter Oleschko
authors.initials: WO
authors.lastname: Arruda
authors.forename: Lineu Cesar
authors.initials: LC
authors.lastname: Werneck
mesh_terms: D000659:AMP Deaminase / Q000172:deficiency*; D001706:Biopsy; D002648:Child; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000201:enzymology / Q000473:pathology; D009224:Myotonia Congenita / Q000201:enzymology* / Q000473:pathology
chemical_list: D000659:AMP Deaminase