The use of urine protein electrophoresis or immunoelectrophoresis of concentrated urine specimens to detect the gamma heavy-chain fragments may be necessary to make the diagnosis. Clinical features include fever, lymphadenopathy, infections caused by hypogammaglobulinemia, and autoimmune hemolytic anemia, all in the context of a variety of lymphoproliferative disorders. This condition has been termed Mediterranean lymphoma because it often occurs in the southeastern portion of that region. The sites that are clinically involved are the areas where secretory IgA is normally localized, predominantly the gastrointestinal tract and, to a lesser extent, the respiratory tract. The intestinal lamina propria is infiltrated with plasmacytoid lymphocytes, and immunoelectrophoresis reveals a monoclonal alpha heavy chain that is not associated with kappa or lambda light chains.
Patients have diarrhea, malabsorption, and abdominal pain.
Therapy with the melphalan-prednisone regimen may be beneficial in such cases. The role of aggressive chemotherapy is being tested. Heavy-chain disease involves the overproduction of the heavy chain of IgM. Clinically, most patients appear to have chronic lymphocytic leukemia. Patients with monoclonal immunoglobulin deposition disease usually present with renal disease, which is characterized by azotemia, proteinuria, and hypertension. Some patients also have cardiac, neurologic, hepatic, and GI manifestations.