Schnitzler syndrome is a rare disorder. The disorder is diagnosed by a chronic red urticarial rash and elevated levels of monoclonal IgM gammopathy. Symptoms may include flairs of fever, joint inflammation, joint pain, bone pain, and enlarged lymph nodes. A monoclonal gammopathy is the uncontrolled growth of a single clone of plasma cells known as immunoglobulin M or IgM. These proteins are supposed to fight foreign substances in the body such as viruses and bacteria, which is why it is referred to as an autoimmune disorder.
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