[Lyme disease could mimic dermatomyositis].

UNLABELLED: We report a dermatomyositis associated with Lyme disease.

OBSERVATION: A 73-years-old woman has developed for 5 months an asthenia, a periorbital oedema and a forearm's skin infiltration without other signs suggesting of dermatomyositis. Laboratory studies showed an elevation of muscular enzymes, and inflammation signs. The skin and the muscles biopsies were compatible with the diagnostic of dermatomyositis. The patient was seropositive for Lyme disease. The patient was efficiently treated with doxycycline.

DISCUSSION: Lyme disease could mimic a dermatomyositis. Indeed, Lyme disease should be considered as a differential diagnosis of dermatomyositis.