The renal scan is more accurate when the baby is at least a month old. All babies with hydronephrosis should be kept on a regimen of preventive antibiotics until these evaluations are completed and the nature of hydronephrosis defined. The majority of these babies will outgrow their reflux in few years and should not need surgery unless they fail to outgrow reflux or develop breakthrough urinary infections. Most blockages eventually require surgical correction. In some babies obstruction appears to be mild, and they may be followed with repeat tests after a few months.
Some babies can have hydronephrosis without reflux or obstruction.
They may be followed with periodic ultrasounds to monitor the degree of hydronephrosis and growth of the kidneys. In babies with a duplication anomaly, the treatment options can vary, depending on several factors. In babies with MCDK, there appears to be a higher incidence of vesicoureteral reflux in the normal, opposite kidney, regardless of whether there is hydronephrosis. There is controversy whether a multicystic dysplastic kidney should be removed or left alone. In general, unless it is causing a problem with the baby s breathing or eating due to its large size and unless there is a question of tumor or blockage, it is usually left alone during infancy and monitored with periodic ultrasounds.