Long-term treatment results of hydronephrosis in children operated in their first year of life. A systematic review

BACKGROUND: Congenital stenosis of the ureterоpelvic junction is the most common cause of hydronephrosis in children. AIM: This systematic review aimed to search and analyze modern literature from 1998 to 2021 on the treatment and postoperative follow-up of children with severe hydronephrosis in the first year of life and study the long-term results. MATERIALS AND METHODS: Literary sources were searched in PubMed, Web of Science, Scopus, Google Scholar, and eLibrary databases. The following keywords were used to search for English sources: congenital hydronephrosis, severe hydronephrosis, operative treatment, uretero-pelvic junction obstruction infant, children, neonatal, and infancy. Five full-text articles that meet the criteria were included for analysis. RESULTS: A total of 355 patients were included in the publications. Antenatal screening was described only in two studies. The average age of children at the time of surgery was five months (one to six months). All the authors noted that due to pyeloplasty in the first year of life, the renal parenchyma exhibited a significant increase in thickness; the indicators in dynamics increased by an average of 1.5 times during the year. The size of the renal pelvis decreased by 50%67%. The data of radioisotope scintigraphy were variable; however, in the long-term period, improvement in renal function was noted in all publications. CONCLUSIONS: This systematic review shows the long-term results of early pyeloplasty in congenital hydronephrosis in young children. A significant decrease in the pelvis and an increase in the thickness of the parenchyma were observed, both of which are an advantage for the restoration of renal function. However, no single algorithm can predict the recovery of renal parenchyma. An accurate assessment of renal parenchymal function should be confirmed by a prospective, randomized, long-term, follow-up study with a large number of cases.