[Content of neutrophil elastase in EPS and seminal plasma: A combined predictor in the diagnosis of type IIIA prostatitis with secondary infertility].

Objective: To investigate the value of the content of neutrophil elastase (NE) in the expressed prostatic secretion (EPS) and seminal plasma (SP) as a combined predictor in the diagnosis of type IIIA prostatitis with secondary infertility.

Methods: This study included 62 fathers (group A) and 67 infertile men (group B), all with type IIIA prostatitis, and another 57 controls with no genitourinary tract disease (group C). We measured the NE contents in the EPS and SP, obtained the results of routine semen and EPS examinations and Chronic Prostatitis Symptom Index (CPSI), and calculated the ratio of EPS NE/SP NE by binary logistic regression analysis.

Results: The combined predictor of type IIIA prostatitis with secondary infertility was SP NE-2 × EPS NE. Among the 129 patients with type IIIA prostatitis, the combined predictor was correlated strongly negatively with the WBC count in the EPS (r = －0.914, P <0.01), negatively with CPSI, sperm concentration, sperm mobility and sperm viability (P <0.01), but not significantly with the WBC count or pH value in the SP (P >0.05). The mean values of the combined predictor in groups A, B, and C were －2 238 (95% CI: －2 595 to －2 054), －1 511 (95% CI: －1 778 to －1 307), and －148 (95% CI: －181 to －118), respectively, with statistically significant differences between the cases and controls as well as between groups A and B (P <0.01). The area under the ROC curve of the combined predictor for the diagnosis of type IIIA prostatitis with secondary infertility was 0.71 (P <0.001).

Conclusions: The content of neutrophil elastase in the EPS combined with that in the seminal plasma contributes to the diagnosis of type IIIA prostatitis with secondary infertility, which is superior to either the neutrophil elastase content in the EPS or that in the seminal plasma used alone.