Baseline renal function and renal ultrasound findings in patients with obstetric fistulas (RENFRU): a prospective cohort study

Abstract

ObjectiveTo describe and compare baseline renal anatomy and renal function in patients with obstetric fistulas, and to evaluate whether preoperative renal testing and imaging may aid with operative decision making.DesignA prospective cohort study.SettingFistula Care Centre in Malawi.PopulationWomen with an obstetric fistula.MethodsBaseline creatinine testing and renal ultrasounds were performed. Surgeons completed a short questionnaire on the usefulness of creatinine and renal ultrasound on operative decision making.Main outcome measuresBaseline creatinine and renal ultrasound findings.ResultsFour surgeons performed operations on 85 patients. The mean creatinine in patients with vesicovaginal fistulas (VVF) was 0.60 ng/ml versus patients with uretero‐vaginal fistulas (UVF) (0.79 ng/ml, P = 0.012). When a grade 3 or more hydronephrosis is absent on renal ultrasound, the negative predictive value of the presence of UVF is 93.3% (95% confidence interval [CI] 88.6–96.2) with a specificity of 97.2% (95% CI 90.3–99.6). In cases of UVF, surgeons found the renal ultrasound results useful or very useful 87.5% of the time, and the creatinine useful or very useful 75% of the time.ConclusionIn this pilot study, most patients with obstetric fistulas presented with a normal creatinine. In the absence of a grade 3 hydronephrosis or above on renal ultrasound, the probability of not having a UVF is 93.3%. Surgeons should consider performing preoperative renal ultrasound testing in all patients with an obstetric fistula, particularly in women with a prior laparotomy, as this population has risk factors for ureterovaginal fistula.Tweetable abstractMost patients with obstetric fistulas have normal renal function. Preoperative renal ultrasounds should be performed.

Management strategies and outcome of ureterovaginal fistulae: A systematic review and meta‐analysis

“…Ultrasound is a noninvasive mode to see the urinary tract and is widely utilized amongst the developing countries (30.4%) (Table S4) as an aid to diagnose fistulae. Chang et al 30 opined that this could be due to the fact that dye test could only diagnose 22% of their UVF cases and hence an ultrasound was added to rule out a UVF. Cystoscopy to visualize the ureteric orifices and rule out a concomitant VVF (26.6%) was undertaken more commonly in the developing countries.…”

The effects of laparoscopic and laparotomy extensive hysterectomy on the safety of ureterovaginal fistula infection in patients with cervical cancer

“…Moreover, Creatinine and urea nitrogen are the main indicators of renal function [15]. Changes in creatinine and urea nitrogen levels are associated with ureteral injuries, including ureterovaginal fistula [16,17]. Therefore, the present study further examined the effects of laparoscopic and laparotomy extensive hysterectomy on creatinine and urea nitrogen levels in patients.…”