Functional outcomes of pediatric laparoscopic pyeloplasty: post-operative functional recovery is superior in infants compared to older children

Abstract

Aim

Laparoscopic pyeloplasty (LP) is less popular and considered less successful in infants compared to older children. There are few reports analyzing the functional results of LP in relation to age of surgery. The aim of this paper is to compare the functional results of LP in infants (group 1) with children over 1 year of age (group 2).

Material and methods

The data of all children undergoing LP between August 2016 and July 2019 were retrospectively analyzed for patient details and follow-up. Only children (n = 135) with at least 1-year follow-up and completed post-operative ultrasound and diuretic renogram were included. All children underwent pre-operative and post-operative ultrasound and diuretic renogram; pre-operative, operative and post-operative parameters were compared between both groups. Statistical analysis was done using software; Mann–Whitney U test, Student t test, and Fisher’s exact test were applied.

Results

There were 71 infants (group 1) and 64 children > 1 year (group 2). Pre-operatively, all kidneys had SFU grade 3 or 4 HDN and 131/135 kidneys had a renal pelvic APD > 20 mm; all kidneys had unequivocal obstruction on DR. At surgery, the preferred drainage method was intra-operative antegrade placement of a JJ stent in 68 (96%) group 1 and 63 (98%) group 2 children. The remaining 4 cases (3 group 1, 1 group 2) had a nephrostomy with trans-anastomotic external stent placement, because the JJ stent could not be negotiated into the bladder. The demographic data and comparison of pre- and post-operative parameters between both groups are summarized in Tables 1 and 2, respectively. Group 1 had significantly more children with antenatal diagnosis of HDN (87% vs 56%, p = 0.0005). The 36 children with antenatal diagnosis in group 2 were initially followed expectantly; the indication for pyeloplasty was deterioration of SRF on serial DR, urinary infection, and pain, in 13, 14, and 9 children, respectively. The operating time was significantly longer in group 2 (p = 0.0001). There was no difference in the success of LP or complication rate in both groups. Group 2 had significantly more children with extrinsic obstruction (1.4% vs 17%, p = 0.001). All children underwent post-operative US and DR; a significant reduction in hydronephrosis (APD) on follow-up was noted in both groups (p = 0.0001). The mean pre-operative SRF in both groups was comparable (p = 0.088). The mean SRF in both groups improved significantly after LP; however, the mean post-operative SRF was significantly higher in group 1 when compared to group 2 (p = 0.0001). Furthermore, group 1 had significantly more kidneys demonstrating > 10% increase in SRF after LP (53% vs 26%, p = 0.0003).

Conclusions

The safety profile and success of LP in infants was comparable to older children. Infant LP took shorter time to perform, while older children had increased incidence of extrinsic obstruction. Infant kidneys demonstrated better functional improvement than older children after LP. These findings should encourage more surgeons to utilize LP for pyeloplasty even in infants.