Objectives: To prove the need for the quantitative full-microflora semen analysis for determining the role of microorganisms in the etiology of asymptomatic inflammatory prostatitis, and to correlate the seminal white blood cell (WBC) counts with interleukin 6 (IL-6) levels.
Methods: Thirty-seven men with asymptomatic inflammatory (National Institutes of Health [NIH] IV category) prostatitis and 32 controls were investigated by using routine semen analysis, IL-6 levels of seminal plasma, and quantitative microbiological analysis of semen.
Results: The IL-6 concentration in seminal plasma was significantly higher in NIH IV category prostatitis patients than in the controls, and was in good correlation with the WBC count in semen (r=0.74, p<0.001). In most of the specimens, the counts of anaerobic microorganisms were equal to or outnumbered the aerobic ones. One to eight different microorganisms could be found in any particular semen sample, and the total concentration of microorganisms ranged from 2.0 to 7.5log(10)CFU/ml. Both parameters were significantly higher in NIH IV category prostatitis patients than in controls (median: 4.8 vs. 3.9log(10)CFU for total concentration, p<0.001; median: 5 vs. 3 for number of different species, p=0.004).
Conclusions: Unlike the controls the NIH IV category prostatitis patients harbour abundant polymicrobial microbiocenosis in their semen, containing anaerobic, microaerophilic and aerobic bacteria. Detection of IL-6 in seminal plasma serves as an additional tool for diagnosing NIH IV category prostatitis.