Vasculitic Mononeuritis Multiplex May Be Misdiagnosed as Carpal Tunnel Syndrome.

Vasculitis is a group of disorders characterized by inflammation and destruction of blood vessels, resulting in ischemic injury to the involved tissue. Sometimes, peripheral neuropathy is one of the first symptoms of systemic vasculitis. Although the classic form of peripheral nervous system vasculitis is mononeuritis multiplex, it can also present as a mononeuritis. In this case report, the patient presented with progressive rapid onset numbness in her right hand for 2 months. She underwent carpal tunnel decompression surgery with initial diagnosis of acute carpal tunnel syndrome but failed to respond to the surgery, and two month later, she presented with foot drop. The final diagnosis was vasculitic mononeuritis multiplex. The present case report demonstrates the importance of identification of median mononeuritis as one of the first presentations of vasculitic disorders and distinction from acute carpal tunnel syndrome. The natural history of many of the systemic vasculitides is rapidly progressive, and they are likely to be fatal without early treatment. In this regard, timely diagnosis of vasculitis is critical because of the vital role of early immunosuppressive therapy in preventing multiorgan damage and decreasing mortality rate.