Background: Because the prevalence of chronic prostatitis (CP) subgroup can not be determined by routine epidemiologic methods (questionnaires), little research has been done with regard to each subtype of CP. In addition, further description of prostate cytokines may help to characterize the different types of prostatitis, and improve our understanding of the prostate immune responses in patients with type-IIIA, type-IIIB and type-IV CP.
Methods and findings: The study population comprised 2,887 men aged 18-78 years at second phase recruitment of a population-based cohort in China. The CP patients and healthy controls were defined by the National Institutes of Health Chronic Prostatitis Symptom Index. Meanwhile, EPS specimens were collected and the leukocyte in EPS was counted. We analyzed the levels of 47 cytokines in the EPS in 118 individuals (30/health, 30/type-IIIB, 29/type-IIIA, 29/type-III IV) randomly selected from present population. Prevalence of CP (26.78%/total, 1.49%/type-IIIA, 6.27%/type-IIIB and 19.02%/type-IV) is prevalent in China, and the prevalence of prostate inflammation (type-IIIA or type-IV CP) between the symptomatic men (type-IIIA/type-IIIA + IIIB, 19.20%) and asymptomatic men (type-IV/type-IV + health, 20.62%) is similar. While IL-1β, IL-6, IL-8, IL-15, IL-17, basic FGF, G-CSF, MCP-1, MIP-1α, MIP-1β, TNF-α, IL-1α, IL-16 and IL-18 levels were much higher in the type-IIIA and type-IV patient groups than in the type-IIIB and control groups, the levels of GM-CSF, PDGF-BB, SCGF-β and TNF-β was significantly lower in the type-IIIA and type-IV groups. The level of IL-1ra was clearly lower in the type-IIIB group, but LIF and β-NGF were elevated in type-IIIB groups of patients compared to controls type-IIIA and type-IV groups.
Conclusions: We think that type-IIIA and type-IV CP may have a similar pathogenesis, but type-IIIB CP may be a different disease with different pathogenesis.
