title: Serum alanine aminotransferase in skeletal muscle diseases.
abstract: Although elevation of the levels of serum alanine aminotransferase (ALT) following liver injury is well known, confusion exists concerning skeletal muscle injury as the cause of this rise. We reviewed the records of 16 patients who had muscle necrosis without evidence of liver disease. The patients were divided into three groups: extreme exercise, polymyositis, and seizures. All patients exhibited markedly elevated creatine kinase and lactate dehydrogenase levels consistent with muscle injury. In acute cases, aspartate aminotransferase (AST) and ALT were both elevated, and the AST/ALT ratio was greater than 3, but this ratio approached 1 after a few days because of a faster decline in AST. In conclusion, this difference in half-life accounts for the comparable AST and ALT levels in our cases with chronic muscle injury.
authors.affiliation: Division of Gastrointestinal and Liver Diseases, Department of Medicine, Keck School of Medicine of the University of Southern California, Los Angeles 90033, USA.
authors.forename: Rahul A
authors.initials: RA
authors.lastname: Nathwani
authors.forename: Shireen
authors.initials: S
authors.lastname: Pais
authors.forename: Telfer B
authors.initials: TB
authors.lastname: Reynolds
authors.forename: Neil
authors.initials: N
authors.lastname: Kaplowitz
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood*; D001219:Aspartate Aminotransferases / Q000097:blood; D002908:Chronic Disease; D003402:Creatine Kinase / Q000097:blood; D004830:Epilepsy, Tonic-Clonic / Q000201:enzymology*; D015444:Exercise; D005260:Female; D006207:Half-Life; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008499:Medical Records; D018482:Muscle, Skeletal / Q000201:enzymology / Q000473:pathology*; D009336:Necrosis; D017285:Polymyositis / Q000201:enzymology*; D012189:Retrospective Studies
chemical_list: D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D003402:Creatine Kinase