Relationship and significance of specific immunoglobulin M antibody response in clinical and subclinical melioidosis.

Thirty-six hospitalized patients with circulating antibody to pseudomonas pseudomallei were classified as having either clinical or subclinical melioidosis after full clinical examinations and supplementary radiological and culture investigations. Qualitative estimations of immunoglobulin M (IgM) antibody response were determined by complement fixation, indirect hemagglutination, and immunofluorescence, and the estimations were correlated with the clinical findings in each patient. An attempt was made to appraise the importance of IgM antibody, as determined by each test, in establishing the diagnosis of clinical melioidosis. Results obtained from serological tests were of no value in differentiating between active and latent infections. However, the IgM-immunofluorescent test appeared to be relevant to the diagnosis of clinical melioidosis, since the presence and absence of IgM-immunofluorescent antibody bore a close relation to clinical and subclinical disease, respectively. Surveillance studies indicated that the IgM-immunofluorescent test may be of value in monitoring the activity and treatment of the infection, since the results of the test were generally negative 3 to 6 months after administration of chemotherapy appropriate for melioidosis.