Subject Recruitment and Urine Collection
This cross-sectional study began following Institutional Review Board approval. Participants gave verbal and written research consent for chart abstraction and urine collection with analysis for research purposes. Between June 2020 and August 2020, adult patients aged 18 or above, diagnosed with OAB were recruited into this study at Nanfang Hospital in China. Patients must complain of urinary urgency, with or without urgency incontinence, usually with frequency and nocturia, in the absence of infection or other pathological changes, in accordance with the 2010 ICS definition of OAB.10 We excluded women who had UTI (based on routine urine test and urine culture) or history of recurrent UTI, antibiotic exposure in the past 4 weeks, immunologic deficiency, neurological bladder, genitourinary cancer, pelvic radiation, urinary stones, untreated symptomatic pelvic organ prolapse (POP) greater than POP-Q stage II, or pregnancy. All participants were required to finish Overactive Bladder Symptom Score (OABSS), and divided into mild and moderate/severe group by total score and the higher the score, the more severe the symptoms of OAB. Scores ≤ 5 were defined as mild symptom, and Scores > 5 were defined as moderate/severe symptom.
Urine was collected using aseptic technique with a sterile catheter by a trained and licensed practitioner. The total volume of urine was emptied from the participant’s bladders and was kept at 4℃, and immediately transferred to laboratory within an hour for centrifugation at 16,000g for 10 min and the resulting pellet were stored at −80℃ until further processing.