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Duplicated or Ectopic Renal Collecting System in Two Adult Emergency Department Patients
Rebecca G Theophanous1, Alexander T Limkakeng1, Joshua S Broder1
1Division of Emergency Medicine, Department of Surgery, Duke University Medical Center, Durham, North Carolina.
Insights
Duplicated ureters, a rare adult diagnosis, can cause flank pain and hydronephrosis. Early recognition in emergency settings is crucial to prevent kidney damage.
Area of Science:
- Urology
- Radiology
- Emergency Medicine
Background:
- Duplicated renal collecting system is a urological anomaly more common in children than adults.
- Diagnosis in pregnant adults is infrequent, and awareness among point-of-care ultrasonography users in emergency departments may be limited.
- This condition can lead to differential hydronephrosis and unequal renal function, potentially causing missed diagnoses if only one ureter is identified.
Background:
Duplicated renal collecting system is a urological anomaly often found in pediatric patients. It is less commonly diagnosed in adulthood, particularly in a pregnant patient. Many point-of-care ultrasonography users may not be aware of this diagnosis, particularly in patients in the emergency department. It is important to recognize the duplicated system because in general, patients will often have hydronephrosis in only one renal pole rather than the entire kidney, which corresponds to an unequal renal function as documented on renal nuclear medicine functional scans. As a consequence, if the sonographer only identifies one ureter and incompletely visualizes the kidney, obstruction of one of the duplicated structures may be missed.
Case Report:
We report 2 cases of duplicated ureter in patients in the emergency department who present with flank pain and urinary symptoms. Both patients were adult females, one pregnant, with duplicated ureter and severe right upper pole hydroureteronephrosis. The first patient was admitted for intravenous antibiotic therapy for pyelonephritis in pregnancy. The second was discharged with oral antibiotics and urgent urologic follow-up. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Duplicated ureter should be considered in patients with recurrent urinary tract infections or enuresis. Point-of-care ultrasonography users should note the differential hydronephrosis between upper and lower renal poles and may visualize duplicate or ectopic ureteronephrosis or ureterocele. Patients should be prescribed prophylactic antibiotics and have urgent urologic follow-up because the untreated condition can lead to irreversible renal damage.
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