Bilateral primary nonrefluxing unobstructed megaureter in an adult: a case report and review of the literature.

BACKGROUND: Bilateral primary nonrefluxing unobstructed megaureter is a rare condition in adults, often identified during evaluation for nonspecific symptoms. Primary nonrefluxing unobstructed megaureter is more commonly diagnosed in pediatric populations, typically through antenatal imaging. CASE PRESENTATION: A 43-year-old South Asian male presented with persistent dull left loin pain lasting 2 weeks. His medical history consisted solely of recently diagnosed type 2 diabetes mellitus, well-controlled with metformin. Imaging studies revealed bilateral distal ureteral dilatation accompanied by hydronephrosis in both kidneys. A computed tomography urogram demonstrated dilated extrarenal pelvis and ureters, with no evidence of obstruction or secondary causes. A mercaptoacetyltriglycine (MAG)-3 renal scan confirmed normal renogram curves, leading to the diagnosis of bilateral primary nonrefluxing unobstructed megaureter. The patient was managed conservatively with regular follow-up, given the absence of significant complications. CONCLUSION: Primary nonrefluxing unobstructed megaureter, while often resolving spontaneously in pediatric cases, requires careful diagnostic evaluation in adults to exclude secondary causes. Conservative management is appropriate in asymptomatic patients or those without significant functional impairment. This case emphasizes the value of comprehensive imaging, including ultrasound, computed tomography and renal scintigraphy, in identifying primary nonrefluxing unobstructed megaureter and guiding management. Long-term follow-up remains essential to monitor for potential complications. Although rare, it is crucial to consider primary megaureter in adult patients presenting with renal-related issues, recognizing that, in exceptionally rare cases, it may present as bilateral, nonobstructive, and nonrefluxing.