Semen granulocyte elastase: its relevance for the diagnosis and prognosis of silent genital tract inflammation

Elastase–inhibitor complex was assessed by immunoassay in the seminal plasma of 312 men attending the outpatient infertility clinic. Using receiver operating characteristic (ROC) curve analysis, elastase at the cut-off value of ≥290 ng/ml was shown to be efficient (sensitivity 79.5%, specificity 74.4%) in the detection of genital tract inflammation as defined by leukocytospermia (>1×106 leukocytes/ml). The prevalence of increased elastase in 292 infertile men was significantly higher (34%) as compared with that (5%) observed in 20 fertile men (P = 0.02). Moreover, high elastase concentration (≥290 ng/ml) was observed in 66 of the 264 men (25%) without leukocytospermia. A significant positive correlation was found between elastase concentration and patient age (r = 0.202, P < 0.0001) and the number of leukocytes (r = 0.330, P < 0.0001). A negative correlation was found between elastase concentration and semen volume (r = –0.146, P = 0.01) and the percentage of spermatozoa with single-stranded DNA (r = –0.194, P = 0.024), but there was no correlation between elastase and sperm reactive oxygen species production. A higher seminal elastase concentration was significantly associated with tubal damage in female partners (P < 0.001). After norfloxacine antibiotic therapy, decrease in elastase concentration was observed in 15 (25%) of the 60 treated patients. Tubal damage in the partner negatively affected the response to antibiotic therapy. In conclusion, granulocyte elastase is a reliable screening test for silent genital tract inflammation of the couple. The elastase–inhibitor complex may have a protective effect in reducing sperm DNA denaturation.