Giant hydronephrosis due to ureteropelvic junction obstruction: A rare case report, and a review of the literature

Abstract

The hydronephrotic kidney, resulting from a ureteropelvic junction obstruction (UPJO), presents commonly as a clinical condition, with the presence of usually no more than 1-2 liters in the collecting system, but a very small number of cases of giant hydronephroses (GHs) has been reported in adults. A GH is defined as the adult renal pelvis containing >1 liter of urine, or at least 1.5% of the body weight. In the majority of cases, the range of the hydronephrotic kidney remains restricted to the renal area. However, the patient described in the present case report had a range for the hydronephrotic kidney which occupied almost the entire abdominal cavity (~24 l), and cases such as these are rarely presented; therefore the aim of the present case study was to document a clear case of GH resulting from UPJO, also accompanied by a review of the current literature. Case report An 18-year-old woman patient was admitted to hospital with complaints of abdominal distension, and the patient had experienced intermittent mild abdominal pain since birth. The abdominal girth had slowly increased in diameter over the previous 18 years, and the patient's general condition of health was poor, presenting symptoms including fatigue, fever, nausea, vomiting, decreased appetite and weight loss. No specific urinary or bowel dysfunction was identified. Clinically, the diagnosis of a giant hydronephrose (GH) was made, and upon physical examination, an extremely distended abdomen was revealed, with a palpable mass in the all-flank region (Fig. 1A). Bowel sounds could not be auscultated, and neither was there any shifting dullness. An examination of the other systems failed to disclose any noteworthy phenomena. The blood laboratory analyses revealed a concentration of blood urea nitrogen of 30.1 mg/dl, and a level of creatinine of 1.56 mg/dl. The level of hemoglobin was 12 g/dl, and the hematocrit was determined to be 45.7%, whereas tumor markers were all revealed to be in normal range, The results of the urine analysis revealed a red blood cell count of 32/high power field (HPF) a white blood cell count of 6/HPF and a yeast cell count of 5/HPF. Blood sugar, phosphate, liver function , serum calcium, serum amylase and electrolyte analyses all yielded results within the normal limits. A diagnostic aspiration performed from the area of abdominal swelling revealed the presence of urine. Ultrasonography revealed the presence of a massive hypoechoic lesion occupying almost the entire abdomen, which exerted pressure on the bowel on the left-hand side. The left kidney appeared normal, although the right kidney could not be identified. A cystic lesion revealed multiple septations, which were likely to have arisen from the right kidney. A computerized tomography (CT) scan revealed a large abdominal mass of water density in the all-abdomen area, which comprised a huge cystic mass (41.5x30.5x30.5 cm; Fig. 2A-C) that, in the right kidney, occupied almost the entire abdominal cavity. This mass had displaced the small intestine, colon, pancreas, spleen and the left kidney. After admission, the cystic mass was punctured, and a total of ~24 l urinal fluid was drained by urethral catheterization over a period of 8 days (3 liters each day). There was an improvement in the general condition of the patient: The distended abdomen decreased in size (Fig. 1B), the level of urea declined to 1.42 g/l, and the level of creatinine was 63 mg/l. The results of subsequent laboratory analyses and urine culture were normal. A subsequent CT scan revealed an almost complete disappearance of the hydronephrosis (Fig. 2D). A right nephrectomy was performed: When an incision was made in the right lumbar region, the cyst presented as a retroperitoneal soft cystic dilatation mass, lacking in definition, measuring almost 30x20x15 cm (Fig. 3), which was able to adhere to adjacent organs, including the liver and the pelvic cavity, lifting the cecum and the ascending colon. The ureter was normal, and ureteropelvic junction obstruction (UPJO) was established as the cause of GH. The pathological tissue sections are shown in Fig. 4.