X-linked immunodeficiency with increased IgM: clinical, ethnic, and immunologic heterogeneity.

Two cases of immunodeficiency with increased IgM are reported. Patient 1 was a black male 3.5 years old who had recurrent pyogenic infections, failure to thrive, oral thrush, and systemic cryptococcal infection. Patient 2 was a 9-year-old white female who had recurrent cervical abscesses. Serum immunoglobulin determinations by radial immunodiffusion in both patients showed marked depression of IgG and IgA and marked elevation of IgM. A low molecular weight circulating monomeric IgM was demonstrated by immunoelectrophoresis and gel filtration in the second patient; this was not present in the first case. In vitro impairment of cellular immunity was observed in both patients. Administration of dialyzable leukocyte extracts (transfer factor) led to improvement of cell-mediated immunity in patient 1. The etiology of this syndrome apparently has several different genetic bases. These patients demonstrate heterogeneity in genetic, ethnic, immunologic, and other features of the syndrome.