POSITIVE MYELOPEROXIDASE STAINING (ENDTZ TEST) AS AN INDICATOR OF EXCESSIVE REACTIVE OXYGEN SPECIES FORMATION IN SEMEN

Purpose: Although the significance of leukocytospermia in semen remain s controversial, evidence exists that white blood cells (WBCs) may adv ersely affect sperm function and act as a potential cofactor in male i nfertility. Nevertheless, the mechanisms by which leukocytes may alter sperm function in vitro is unknown. Recent investigations suggest tha t reactive oxygen species (ROS) generated by the polymorphonuclear (PM N) granulocytes could adversely affect sperm function. The objective o f this study was to investigate the relationship between the presence of leukocytospermia as determined by the Endtz test and the excessive formation of ROS. Methods: The WBC concentration and ROS formation in human semen, obtained from men consulting for infertility, were assess ed and compared to that of normal donors. ROS was measured by a chemil uminescence assay using luminol and a Berthold luminometer. The WBC co ncentration was determined with a myeloperoxidase staining technique ( Endtz test). Specimens were obtained from 94 subjects (20 donors, 74 p atients). Results: Of the 20 donors, 2 were Endtz positive and ROS pos itive; 18 were Endtz negative with 2 (11%) ROS positive. In the patien t group (n = 74), 26 (35%) were ROS positive, and 17 were Endtz positi ve and found to be ROS positive. Of the 57 Endtz-negative patients, 9 (15%) were ROS positive. The positive Endtz rest results correlated st rongly with positive ROS formation in patients and donors (P < 0.001). Conclusions: Our results indicate that the simple, cost-efficient End tz test could be used as an indicator of excessive ROS formation in se men.