From diagnosis to remission: place of MRI in eosinophilic fasciitis.

Eosinophilic fasciitis is a rare disease, but it must be considered in patients with adult myalgia. Here, we report the case of 32-year-old man who presented with a 4-month history of bilateral myalgia of the lower limbs, which subsequently spread to the upper limbs. There was no specific medical history, no trauma, and no intense activity. Physical examination revealed induration of the skin with irreducible flexion of the fingers as observed in scleroderma. Laboratory examination showed peripheral eosinophilia associated with moderate elevation of both the erythrocyte sedimentation rate and C-reactive protein. No infectious, neoplastic, hemopathic, or immunological abnormality was detected. Magnetic resonance imaging (MRI) showed thickening of the muscular fascias of the thigh in high signal intensity on T2-weighted images, slightly enhanced after contrast agent injection on T1 images, without myositis. MRI-guided muscle biopsy demonstrated fascia infiltration characterized by mononuclear inflammatory cells and polynuclear eosinophils. A diagnosis of eosinophilic fasciitis was confirmed and the patient received prednisolone. One month later, he reported improvements in general health, pain, motion, joint mobility, and skin induration associated with normalization of both hypereosinophilia and biologic inflammation. After 12 months, clinical MRI and laboratory parameters were normal and the patient was considered to be in clinical remission.