A single centre experience of percutaneous nephrolithotomy in infants and its long-term outcomes

Abstract

Renal stones in infants requiring Percutaneous nephrolithotomy (PCNL) is rare. There is insufficient literature on the long-term implications of PCNL in growing kidneys of these children. To review our experience of PCNL amongst infants i.e., < 1year of age and to analyse the safety and efficacy of this procedure and assess its long-term renal outcomes. This was a retrospective analysis of a prospectively maintained data base between 2005 and 2020. All infants with unilateral renal stones >12mm underwent PCNL. Changes in the serum creatinine, estimated glomerular filtration rate and renal size prior to the PCNL and at the last follow up were monitored. The demographics, clinical profile, operative details, post-operative complications and follow up data were collated and analyzed. 86 children were diagnosed with renal stones of whom, 24 infants met our inclusion criteria and were included in the review. The average age was 9.75 months with fever being the commonest presenting symptom. Five infants were diagnosed with metabolic abnormalities, hypercalciuria being the commonest. Majority of the infants (22) had single stones and the lower calyx was the commonest site (50%). The mean stone burden was 19.5mm. The stone free rate was 91% during the primary PCNL, which increased to 100% after re-do PCNL. The overall complication rate was 16% which was graded by the modified Clavien Dindo scale for surgical complications. The median follow up period was 144 months and average age at the last follow up was 10.5 years. At the last follow up, a mean serum creatinine of 0.4mg/dl, mean estimated glomerular filtration rate of 98ml/min/1.72m2 and a mean renal size of 8.3cm was recorded, which was comparable to that of a normal child, thus signifying no deterioration of renal functions and renal growth. Three children showed the presence of cortical scars on an isotope scan at follow up. However, all the 24 operated renal units demonstrated preserved renal functions. PCNL performed during infancy does not hinder the growth potential of the kidney. Each of the 24 children achieved the target renal size and estimated glomerular filtration rate corresponding to the duration and body size at the end of the follow-up. Thus, PCNL in infants <1 year of age is safe and effective with no adverse effects at long term follow-up.