[McArdle's disease revealed by acute low back pain].

GSD 5 is a disease characterized essentially by muscular fatigability during exercise. The case reported here is original in the clinical circumstances leading to the diagnosis, i.e., inaugural acute low back pain with rhabdomyolysis. This symptomatology had already been described before, but in a patient whose diagnosis was already known. Spinal MRI showed non-specific muscle inflammation and necrosis. Muscle biopsy only found necrosis but no pathological elements typical of the diagnosis. If the symptoms are suggestive, it may be preferable to directly perform a non-ischaemic forearm exercise test, in order to go directly to molecular genetic analysis. There is no specific curative treatment of GSD 5. However, some measures can be implemented to limit the symptoms, such as learning physical exercises, limiting intense efforts and adopting dietary recommendations.