Morbidity and significant bacteriuria after urodynamic studies

Abstract

Introduction: Urodynamic pressure flow studies (PFS) are increasingly utilised in assessing patients with lower urinary tract (LUT) dysfunction. Although minimally invasive, there is theoretical risk of morbidity and infection. This paper looks at the morbidity, the incidence and natural history of significant bacteriuria (SBU) occurring after PFS. Materials and Methods: Patients undergoing PFS in a General Hospital and meeting entry criteria were enrolled with informed consent. Each had urine culture specimens collected at the time of PFS (D0), 3 (D3) and 7 (D7) days after PFS and a 7-day symptom log. Results: Ninety-three patients (44 males and 49 females), with a mean age of 52.2 years (range, 17 to 89) were evaluated. Twenty-five per cent (23/93) developed irritative LUT symptoms after PFS, but only 2/23 had a positive urine culture. All symptoms in culture-negative patients resolved within 5 days and none had sought medical treatment. The overall incidence of SBU was 13.9% (13/93) of whom 11/13 (95.7%) were asymptomatic. Majority of SBUs were detected on D3 but 30% developed late (D7). All asymptomatic SBUs were treated expectantly and 70% (7/11) resolved spontaneously by D14. 81.8% of organisms cultured were coliforms, and 18.2% enterococcus. There was no statistically significant correlation between age, sex, post-void residual and bladder outlet obstruction (diagnosed by PFS) and post-PFS morbidity or SBU. Conclusion: Symptoms occurring after PFS are mild, transient and rarely associated with infection. SBU after PFS is largely asymptomatic and self-resolving. Given the extremely low rate of symptomatic infection, antibiotic prophylaxis is not necessary.