Localized striated muscle vasculitis in rheumatoid arthritis.

Rheumatoid arthritis (RA) is one of the most prevalent connective tissue diseases and can be complicated by vasculitis with systemic manifestations. Rheumatoid vasculitis can range in severity from a widespread, life-threatening disease refractory to treatment to a more benign, localized disease responsive to treatment. We describe here a patient with RA who presented with bilateral calf muscle pain secondary to rheumatoid vasculitis. The patient had intractable calf muscle pain which did not respond to nonsteroidal anti-inflammatory drugs and muscle relaxants. He did not have any other manifestations of rheumatoid vasculitis such as skin ulcers, peripheral neuropathy, or gastrointestinal involvement. A thorough diagnostic work-up concluding with a muscle biopsy revealed a non-necrotizing small vessel vasculitis. The patient's symptoms responded very well to a course of steroids and he required no additional cytotoxic agents. This case illustrates that rheumatoid vasculitis can present as an isolated striated muscle vasculitis characterized by a relatively benign course and prompt resolution with the initiation of steroids. Clinicians need to be aware that such a phenomenon can exist to facilitate early recognition and appropriate treatment.