Evaluation of the direct and indirect mixed antiglobulin reaction with latex particles for the diagnosis of immunological infertility.

The direct Mixed Antiglobulin Reaction (MAR test) is a simple method for the detection of auto-antibodies attached to spermatozoa in fresh semen. The test was improved by using IgG-coated latex particles (SpermMAR) instead of coated red blood cells. A positive direct MAR test with adherence of latex particles to 40% or more of the motile spermatozoa was found in 16 out of 312 men (5%) consulting for infertility, but never in fertile controls. The percentage of motile spermatozoa reacting with the coated latex particles was correlated significantly with the serum titre of sperm agglutinins assessed by the tray agglutination test. The direct MAR test on semen was highly specific but rather insensitive, particularly if the serum titre of agglutinins was low. The same kit (SpermMAR) can be used to detect circulating sperm antibodies in serum of male or female patients with the indirect mixed antiglobulin reaction. The indirect MAR test discriminated clearly between serum with low (less than 1/32) or high (greater than 1/32) titres of circulating agglutinins assessed by the tray agglutination test. Considering their simplicity and accuracy, both the direct test on semen and the indirect spermMAR test on serum should be included in the routine evaluation of the infertile couple.