Evaluation of the Outcome of Pyeloplasty in Children with Poorly Functioning Kidneys due to Unilateral Ureteropelvic Junction Obstruction.

Abstract

To analyze the outcome of upfront pyeloplasty in kidneys of children with unilateral ureteropelvic junction obstruction (UPJO). Thirty-three consecutive cases with split renal function (SRF) of ≤20% on dynamic renal scintigraphy (DRS) underwent upfront pyeloplasty with a nephrostomy tube and trans-anastomotic stent. Outcome was analyzed based on symptomatic relief, nephrostomy output, surgical complications and changes noted in pre-and post-operative findings on renal ultrasound (US), and DRS. The most common symptom was abdominal lump in <5-year age group (79%) and abdominal pain in >5-year age group (93%). Postoperatively, symptoms were relieved in all (100%), parenchymal thickness (PT) on US improved in 82% and SRF improved significantly (>5%) in 75.8% of patients. The improvement was more significant in patients with abdominal lump and large kidneys. The mean nephrostomy output showed an inverse relationship with age at pyeloplasty and a direct correlation with the change in PT and SRF. The degree of improvement in SRF also was inversely related to the age at pyeloplasty with a significantly better outcome in <2-year-age. Although age at pyeloplasty, nephrostomy output and change in PT individually showed significant correlation with change in SRF, multiple regression analysis showed PT as the only significant factor. Upfront pyeloplasty should be the first option in children with poorly functioning kidneys as it has a favorable outcome in almost all the cases with a very low incidence of complications. The degree of improvement in SRF can be predicted by the nephrostomy output and improvement in PT on US.