ELEVATED LEVELS OF SERUM IMMUNOGLOBULINS IN ASYMPTOMATIC CARRIERS OF CLOSTRIDIUM-DIFFICILE

Serum levels of IgA, IgM, and polyvalent immunoglobulins reactive with Clostridium difficile were determined by ELISA for asymptomatic carri ers (n = 5), symptomatic individuals (n = 21), and a pool of 30 ''norm al'' individuals. Mean IgA concentrations expressed as optical density (OD +/- SD) were significantly higher (P < .001) for asymptomatic car riers (1.252 +/- 0.516) than for symptomatic patients (0.374 +/- 0.145 ). Mean serum IgM levels also were significantly higher (P < .001) for carriers (1.456 +/- 0.582) than for symptomatic patients (0.727 +/- 0 .331), as were mean values for polyvalent immunoglobulins (2.25 +/- 0. 718 for carriers vs. 1.457 +/- 0.574 for symptomatic patients; P < .05 ). Although the patient populations were small, the levels of immunogl obulins reactive with C. difficile antigens differed significantly. Th is difference might reflect the ability of the host to mount an immune response and might be a factor influencing whether a patient develops disease due to this organism. The ability to detect differences in im munoglobulin levels might also help differentiate infection from colon ization.