Cell-mediated immune status of children with recurrent infection.

Objective: To evaluate the cell-mediated immune status of children with recurrent respiratory tract infections.

Design: We evaluated the cell-mediated immune status of 76 patients referred because of recurrent infection. Patients were divided into those with serologic abnormalities and those without such findings. Twenty-three healthy children served as control subjects. Studies of lymphocyte phenotype included CD4+ CD29+ cells (an immunologically mature phenotype), lymphocyte proliferation studies, cytokine production including interleukin-2 (IL-2), IL-4, IL-6, and interferon gamma), and measurement of in vitro IgM and IgG synthesis.

Results: Lymphocyte proliferation and T-cell phenotype were similar in both patient groups as well as in control subjects. The proportions of CD4+ CD29+ cells at different ages were similar in all groups. Patients with serologic abnormalities (e.g., partial IgA deficiency, partial IgG subclass deficiency) produced more IL-2 and IL-4 than did other patients. The control population had greater spontaneous IgM and IgG synthesis than the patient groups.

Conclusion: Routine studies of T-cell function of patients with recurrent infection provide little information useful in making clinical decisions.