Urinary tract infection after urodynamic studies in women: incidence and natural history

Objective To study the incidence, natural history and symptomatic effects of bacteriuria after urodynamic studies in women. Patients and methods In a prospective study in the urogynaecology clinic of a large District General Hospital, 214 women (mean age 52.3 years, range 23–81) underwent urodynamic studies. Bacteriuria was detected by semiquantitative culture at 2 and 7 days after the test. Women completed a 7-day diary of symptoms and events. Results The incidence of bacteriuria after urodynamic studies was 7.9%. Bacteriuria was transient in four of 17 women but persisted in nine and developed late in four; only one of 17 infections gave rise to symptoms. Irritative bladder symptoms after the test occurred in 34% of women, but only three went to their doctors because of concern about a possible urinary tract infection. Advancing age was the only variable associated with bacteriuria after urodynamic studies (P=0.05). Menopausal status, past history of urinary tract infection, number of urethral instrumentations required, order number in a session, peak urinary flow rate and urodynamic diagnosis were not associated variables. Conclusions In a large series of women presenting to a urogynaecology clinic, urodynamic investigations were associated with a high incidence of transient irritative symptoms but a low incidence of bacteriuria (8%). Infection was asymptomatic in most patients, but its natural history was unpredictable. Transient, persistent and late cases of bacteriuria all occurred. In this population, urodynamic studies are associated with a low level of morbidity.