Evaluation of Interleukin-8 (IL-8) as Indicator of Inflammation in Prostatic Secretions

W Hochreiter,1 R Nadler,1 A Koch,2 P Campbell,2, A Schaeffer1

Northwestern University Medical School, Departments of 1 Urology and 2Medicine, Chicago, IL

Introduction Chronic prostatitis/Chronic Pelvic Pain Syndrome (CPPS) is a disorder characterized by pelvic pain and varying degrees of inflammation in expressed prostatic secretions (EPS). To provide an objective parameter of inflammation we measured the inflammatory cytokine IL-8 in EPS of healthy men, men with benign prostatic hyperplasia (BPH), and men with prostatitis/CPPS.

Materials and Methods Thirty-seven men: healthy controls (n=8), BPH (n=4), acute bacterial prostatitis [NIH category 1] (n=2), inflammatory CPPS [NIH category Illa] (n=11), non-inflammatory CPPS [NIH category Illb] (n=8), and asymptomatic inflammatory prostatitis [NIH category IV] (n=4) were evaluated for EPS IL-8 by ELISA.

Results IL-8 was detectable in all patients (threshold of detection: 10 pg/ml). Mean IL-8 levels were similar in controls (3,084 pg/ml), BPH (3,665 pg/ml), and Illb (2,735 pg/ml). IL-8 levels were higher in categories 1(9,636 pg/ml), IIIa (10,774 pg/ml), and IV (1,0931pg/ml). There was a statistically significant difference between controls versus 1, Illa, and IV (p<0.05). Overall, there was a correlation between inflammatory reaction and IL-8, but no correlation between clinical symptoms and IL-8.

Conclusions IL-8 is frequently elevated in the EPS of men with acute bacterial prostatitis, CPPS Illa, and asymptomatic inflammatory prostatitis category IV. Known to be a direct mediator of leukocyte accumulation and activation at inflammatory sites, it suggests that IL-8 is at least in part responsible for the presence of inflammatory reaction in the prostate. It may help to better characterize the inflammatory responses in CPPS patients.