Urethral discomfort without inflammatory response, the possible causes are urethral stones, non-bacterial pathogens infection, urethral syndrome, chronic prostatitis and so on. 1. Urethral calculi: small urethral calculi are not easily embedded and cause significant pain when discharged with urine, but may cause friction damage to the urethral mucosa, and cause discomfort symptoms. 2. Non-bacterial pathogen infection: mycoplasma, chlamydia and other non-bacterial pathogen infection, may not cause obvious inflammatory reaction, so the relevant bacterial culture and inflammation laboratory indicators may not be abnormal, but can stimulate the urethra to produce uncomfortable symptoms. 3. Urethral syndrome: Urethral syndrome is mostly seen in women, patients with urinary frequency, urgency, urethral discomfort and other urinary tract irritation symptoms, but several times urine bacteriological examination are negative, may be related to the forced urethral muscle or bladder sphincter function incoordination, gynecological diseases, perianal disease, neurological anxiety and other factors. 4. Chronic prostatitis: Chronic prostatitis can be divided into bacterial and non-bacterial, and the latter often has no relevant inflammatory indicators of abnormality, the urine culture is no bacterial growth, but there will be long-term repeated perineal discomfort, urethral pain, urinary frequency, urinary discomfort. Urethral discomfort but no inflammatory response to a number of reasons, it is recommended that patients go to the hospital as soon as possible, timely identification of the causes to be targeted treatment.