Measurement of Toxoplasma IgM by a microparticle capture enzyme immuno-assay.

The microparticle capture enzyme immuno-assay (MEIA) is an automated system for measuring specific antibody by interaction with antigen-coated particles. An MEIA method for detecting toxoplasma-specific IgM was compared with established reference methods. The MEIA had an acceptable level of sensitivity and reproducibility and was easier to perform than conventional tests, but it required expensive, dedicated equipment and, in our study, false positive results were recorded with 7% of samples. MEIA could be used to investigate immunocompetent patients with suspected toxoplasmosis but positive findings should be confirmed by an alternative form of assay. The technique is not suitable for the investigation of neonates, for which a more sensitive method is required.