Diagnostic différentiel en cas de présomption de myopathie atypique des équidés : illustration au travers de cas référés à la Faculté de Médecine Vétérinaire de l’Université de Liège au cours du printemps 2003

Atypical myopathy is a frequently fatal disease inducing extensive and severe muscular damage, occurring during autumn and spring in grazing horses. The main features of the syndrome are the sudden onset of non pathognomonic symptoms such as weakness, stiffness, sudation, recumbency and when observed, emission of dark urine. Confirmation of the diagnosis is of paramount importance since the disease can be recurrent on limited geographic area. This paper discusses the methodology applied on 7 clinical cases referred with a symptomatology suggestive of atypical myopathy to the Faculty of Veterinary Medicine at Liege University during the spring 2003. Two of those cases were confirmed for atypical myopathy. A presumption of atypical myopathy may be drawn on history and clinical signs. On living animals, the serum concentration of the creatinine phosphokinase enzyme is the most useful biochemical tests as an aid to diagnosis because it confirms the presence of muscle damage. Nevertheless, the definitive diagnosis requires the histological examination of specific muscular samples obtained post-mortem.