Congenital anomalies of the kidney and urinary tract: Case

This infant has a right multicystic dysplastic kidney with a non-functioning right kidney on the DMSA scan and a grade 3 vesicoureteral reflux into the left, the solitary functioning kidney. The right multicystic dysplastic kidney is a parenchymal CAKUT, and the contralateral reflux into the left kidney is a common and important association, because the left kidney carries the entire renal function. The febrile urinary tract infection at 3 months reflects the reflux into the left kidney, and the prevention of further infection is the priority. ^[6]

Clinical findings

The key clinical findings are the non-functioning right multicystic dysplastic kidney, the grade 3 vesicoureteral reflux into the left kidney, the history of one febrile urinary tract infection, the normal blood pressure, the growth on the 25th centile, and the serum creatinine of 42 micromoles per litre. The DMSA scan confirms that the right kidney is non-functional and the left kidney has 100 percent of the total function with no cortical scarring, which is reassuring but places the entire renal burden on the refluxing left kidney. ^[5]

The differential for the contralateral anomaly in a child with a multicystic dysplastic kidney includes vesicoureteral reflux, which is the most common, a ureteropelvic junction obstruction, and renal hypoplasia. The MCUG has confirmed the grade 3 reflux, and the DMSA has shown no scarring in the left kidney. The serum creatinine is normal for age, but the long-term risk to the solitary functioning kidney is the central concern. ^[6]