Finally, we found that the expression of CXCL13 was positively correlated with PV and tPSA, with no relation to other parameters, including age, body mass index (BMI), free PSA (fPSA), the maximum flow rate (Qmax), residual urine (RUV), international prostate symptom score (IPSS) or nocturnal enuresis. The gene discussed is CXCL13; the disease is prostatitis.