A congenital megaureter is an anomaly of the urinary tract characterized by an abnormally dilated ureter, usually accompanied by renal pelvis dilation. A substantial number of patients are asymptomatic, whereas the development of urinary tract infections, together with hematuria, fever, and abdominal pain are main findings in symptomatic cases. The diagnosis can be made through imaging studies, with grey-scale ultrasonography, voiding cystourethrography, and intravenous urography serving as the procedures of choice.
Congenital anomalies of the urinary tract are considered to be rather common in the general population, with an incidence of 1 in 500 individuals . A congenital megaureter, an important cause of obstructive uropathy in the neonatal and pediatric population , is defined as abnormal dilation of the ureter, together with dilation of the renal pelvis in most cases . Several types have been described in the literature - obstructed or nonobstructed and refluxing or nonrefluxing   . The clinical presentation of a congenital ureter is often asymptomatic and the majority of patients are incidentally diagnosed on prenatal ultrasonography . When the congenital megaureter is not visualized during this period, recognition might be delayed until adulthood due to the absence of complaints  . Symptomatic cases, on the other hand, may manifest as more frequent urinary tract infections (UTIs), recurrent urolithiasis, nonspecific abdominal pain, and fever  . Hematuria (both microscopic, and in the presence of calculi, macroscopic) can also be a part of the clinical presentation . Renal failure is rarely seen due to congenital megaureter, but renal dysplasia and hydronephrosis are reported as more severe complications  .
Imaging studies are the cornerstone for recognizing a congenital megaureter, but the role of the physician in raising clinical suspicion through a detailed physical examination and history taking is essential in order to make a presumptive diagnosis . Signs and symptoms (if present) should be assessed during the interview with the patient (although the young age of the patient often necessitates collection of information from the parent) and during the physical exam, after which several procedures can be employed. Grey-scale ultrasonography (US), being noninvasive and readily used both in the prenatal and postnatal setting, is widely described as the optimal method for detecting a congenital megaureter  . In addition, several other methods are recommended    :
In addition, magnetic resonance urography (MRU), intravenous pyelography (IVP) and X-ray urography, but also computed tomography (CT) have all been described as very good methods to confirm a congenital megaureter, dilation of the renal pelvis and urolithiasis   .