Arterio-Ureteral Fistula: A Rare Elusive Cause of Significant Hematuria.

Arterioureteral fistula (AUF) is a direct communication between the ureter and an artery and is a rare cause of catastrophic, life-threatening haematuria. Fistulation may occur between the ureter and the abdominal aorta, common iliac, external and internal iliac, and inferior mesenteric arteries, and is typically observed in patients with a prior history of pelvic radiotherapy, oncological pelvic surgeries, aortoiliac vascular procedures, and pelvic exenteration. There is also an increased frequency of cases amongst patients who have undergone urological diversion surgeries and in those with chronic indwelling ureteric stents requiring repeated exchange. As AUF is so rarely encountered in clinical practice, the urologist may fail to appreciate its presence until late in the patient's presentation; such diagnostic delay is associated with high mortality and thus rapid clinical suspicion and investigative action are necessary. There are sporadic cases of this rare entity mentioned in literature. In this report, we present two cases as well as a review of the literature. A 73-year-old female presented with repeated episodic haematuria for a week in whom the cause of symptoms remained persistently elusive despite repeated imaging and operative approaches. An eventual diagnosis of a secondary right internal iliac-ureteral fistula was ascertained on a subsequent digital subtraction angiography of the renal tract. The fistula was embolised using an endovascular approach. The patient remained stable post emobilisation and was successfully discharged shortly after the procedure. In the second case, a 51-year-old female, presented with hematuria from her ileal conduit for a few days. Initially, the cause of symptoms was thought to be due to ureteric stents. During a change in her stents, brisk bleeding led to further investigation including an iliac angiogram confirming bleeding from the left common iliac artery. She had a covered common iliac artery stent, which successfully controlled her bleeding This report emphasizes the diagnostic difficulty of AUF, outlines the management principles of this rare disease, and aims to increase awareness of this rare yet potentially lethal phenomenon among practitioners of urology and interventional radiology.

A Prospective Multi-institutional Study Using a Novel Safety Valve for the Prevention of Catheter Balloon Inflation Injury of the Urethra.

PURPOSE: We prospectively assessed the ability of a novel transurethral catheterization safety valve to prevent urethral catheter balloon injury in a multi-institutional clinical setting. MATERIALS AND METHODS: A prospective, multi-institution study was conducted. The safety valve was introduced for urinary catheterization in 6 hospital groups (4 in Ireland; 2 in the UK). The safety valve allows fluid in the catheter system to vent through a pressure relief valve if attempted intraurethral inflation of the catheter's anchoring balloon occurs. Device usage was studied over a 12-month period, with data recorded using a 7-item data sticker containing a scannable QR code. "Venting" through the safety valve during catheterization was indicative of prevention of a urethral injury. An embedded 3-month study was conducted in 3 centers, with any catheter balloon injuries occurring during catheterization without safety valve use referred to the on-call urology team recorded. Health economic analyses were also performed. RESULTS: During the overall 12-month device study phase, 994 urethral catheterizations were performed across study sites. Twenty-two (2.2%) episodes of safety valve venting were recorded. No urethral injuries occurred in these patients. In the embedded 3-month study, 18 catheter balloon injuries were recorded in association with catheterizations performed without the safety valve. Based on confirmed and device-prevented urethral injuries, the injury rate for urethral catheterization without safety valve use was calculated to be 5.5/1,000 catheterizations. CONCLUSIONS: The safety valve has the potential to eliminate catheter balloon injury if widely adopted. It represents a simple, effective, and innovative solution to this recurring problem applicable to all patient cohorts.

A Prospective Multi-Institutional Evaluation of Iatrogenic Urethral Catheterization Injuries.

OBJECTIVES: To perform a multi-institutional investigation of incidence and outcomes of urethral trauma sustained during attempted catheterization. PATIENTS & METHODS: A prospective, multi-center study was conducted over a designated 3-4 month period, incorporating seven academic hospitals across the UK and Ireland. Cases of urethral trauma arising from attempted catheterization were recorded. Variables included sites of injury, management strategies and short-term clinical outcomes. The catheterization injury rate was calculated based on the estimated total number of catheterizations occurring in each center per month. Anonymised data were collated, evaluated and described. RESULTS: Sixty-six urethral catheterization injuries were identified (7 centers; mean 3.43 months). The mean injury rate was 6.2 ± 3.8 per 1000 catheterizations (3.18-14.42/1000). All injured patients were male, mean age 76.1 ± 13.1 years. Urethral catheterization injuries occurred in multiple hospital/community settings, most commonly Emergency Departments (36%) and medical/surgical wards (30%). Urological intervention was required in 94.7% (54/57), with suprapubic catheterization required in 12.3% (n = 7). More than half of patients (55.56%) were discharged with an urethral catheter, fully or partially attributable to the urethral catheter injury. At least one further healthcare encounter on account of the injury was required for 90% of patients post-discharge. CONCLUSIONS: This is the largest study of its kind and confirms that iatrogenic urethral trauma is a recurring medical error seen universally across institutions, healthcare systems and countries. In addition, urethral catheter injury results in significant patient morbidity with a substantial financial burden to healthcare services. Future innovation to improve the safety of urinary catheterization is warranted.