Ureteropelvic Junction Obstruction Mimicking an Intraabdominal Mass in a Child

Giant hydronephrosis is a rare entity that may mimic benign and progressive intraabdominal cystic masses. It is defined as the presence of more than 1 liter of fluid in the collecting system of the kidney. Despite the increase in the use of antenatal ultrasound, giant hydronephrosis may still be seen in the pediatric population. Here, we report a case of giant hydronephrosis due to ureteropelvic junction obstruction mimicking an intraabdominal mass in an 11-year-old male who presented with abdominal pain and other gastrointestinal symptoms.