The syndrome of hypergammaglobulinemia M, eosinophilia, edema, and fatigue. Immunologic studies and long-term evaluation of two patients.

2 patients with an elevated serum IgM, eosinophilia, nonpitting edema, and fatigue previously reported, were reevaluated. Their clinical course remains relatively benign without evidence of organ damage after 19 patient years of evaluation. Corticosteroid therapy suppresses clinical manifestation, although IgM levels remain elevated. The numbers of T and B cells are normal. T cell function as studied by phytohemagglutinin stimulation of lymphocytes was normal.