Objective: Levels of urinary prostatic exosomal protein (PSEP) were detected to evaluate the clinical potential of PSEP as a diagnostic marker of chronic prostatitis (CP).
Materials and methods: The level of urinary PSEP was measured in 412 cases by an enzyme-linked immunosorbent assay kit, including 202 controls and 210 CP cases. Of the CP patients, 116 cases met the definition of the USA National Institutes of Health category III (NIH-III), with 60 cases of NIH-IIIA and 56 cases of NIH-IIIB. The ages, body mass indexes (BMI), white blood cell (WBC) levels in expressed prostatic secretions (EPS), lecithin body counts in EPS, urine PSEP levels both before and after prostate massage obtained from the CP patients and NIH-CPSI scores were analyzed.
Results: In the diagnosis of CP, the PSEP contents in the urine samples before and after prostate massage manifested a sensitivity of 86.93% vs. 61.06%, and a total coincidence rate of 85.24% vs. 61.06%, respectively. The area under the ROC curve was 0.926 vs. 0.709 for the before and after massage PSEP contents, respectively. Besides, during the follow-up of patients with CP, the improvement in symptoms was not correlated with the level changes of PSEP.
Conclusion: Measurement of PSEP levels for the clinical diagnosis of CP is objective and painless. It could be a novel, simple, and noninvasive method for the diagnosis of CP. However, differences in fluid intake may result in a concentration or dilution of urine, which would ultimately affect the judgment of PSEP results.
Keywords: Chronic prostatitis; Diagnosis; Prostate; Prostatic exosomal protein.