[Intramuscular vascular malformations as a differential diagnosis of focal myositis].

[focal myositis]

Focal myositis constitutes an original and rare pathological entity , characterized by a localized inflammation within skeletal muscle , presenting as a soft tissue painful tumefaction . Diagnosis requires histological confirmation because of its non-specific clinical feature and the numerous differential diagnoses .We report a 27 year -old man who presented with suggestive symptoms of focal myositis . MR imaging and echography were compatible with this diagnosis but also demonstrated the existence of a vascular component within the tumefaction . The diagnosis of a benign vascular malformation with intramuscular development was made by a surgically guided biopsy .Vascular malformations are histologically heterogeneous with extremely variable clinical expressions . When they develop within skeletal muscle , they may mimic focal myositis . Hence , their diagnosis has to be evoked before performing muscle biopsy , because of the potential hemorrhagic risk .