Background: Schnitzler's syndrome is a rare etiology of chronic urticaria. The disease is characterized by the association of chronic urticaria, intermittent chronic fever, bone pain, osteosclerotic bone lesions and IgM monoclonal gammapathy. More than fifty patients with this syndrome have been reported since Schnitzler reported the first case in 1974, but neuropathies are seen only in a few cases.
Case report: Our patient developed, eight years after the diagnosis of Schnitzler'syndrome, a peripheral sensitive neuropathy. Anti-myelin-associated glycoprotein antibodies were not significant. A nerve biopsy specimen has revealed aspecific demyelinization. Direct and indirect immunofluorescence were negative. We conclused is that our patient presented chronic inflammatory demyelinating polyneuropathy.
Discussion: We found one published case of Schnitzler's syndrome and myelin-associated glycoprotein reactive peripheral neuropathy. The diagnosis of chronic inflammatory demyelinating polyneuropathy is a diagnosis of elimination. It is not the most common neuropathy associated with monoclonal gammapathy. To the best of our knowledge, it is the first case of Schnitzler's syndrome with this type of neuropathy. But there are some descriptions of chronic inflammatory demyelinating polyneuropathy presenting autoantibody activity against a myelin component, up to two years after the diagnosis of IgM monoclonal gammapathy.