Role of toxoplasmosis in the aetiology of some cardiac diseases: an immunobiological investigation.

The Sabin-Feldman dye test was used to show the presence of toxoplasma antibodies in 183 patients with cardiac disease, as well as in two control groups (A and B), comprising 183 and 2186 healthy subjects, respectively. Toxoplasma specific antibodies were found in 157 (86%) patients with cardiac disease, 39 (21%) of whom had high titres. The prevalence of toxoplasma antibodies was considerably lower than that of control groups: 94 (51%) in group A and 1276 (58%) in group B. High titres were present in 8 (4%) and 83 (4%), respectively. Immunofluorescence antibody testing showed IgM antibodies in five patients, three of whom had the organism itself recovered from the blood or lymph nodes. Chronic or latent toxoplasma infection as a cause of cardiac disease is not as uncommon as is generally thought.