Impact on clinical outcome of segmental vs diffuse parenchymal thinning in infants with prenatal urinary tract dilation

Objective: To determine the difference in renal function and rate of surgical intervention between neonates with diffuse and segmental parenchymal thinning. Materials and Methods: First postnatal ultrasonography images of neonates with prenatal urinary tract dilation were evaluated and measurements taken. Neonates with parenchymal thinning were categorised into segmental and diffuse parenchymal thinning groups using the medullary to intermedullary ratio. A statistical correlation of differential renal function and rate of surgical intervention between the two groups was calculated and evaluated using an independent t-test and Kaplan-Meier curve with Log-rank test, respectively. Results: Of the 20 neonates, 10 had segmental parenchymal thinning, while the other 10 had diffuse parenchymal thinning. Mean differential renal function was 49.3% in the segmental parenchymal thinning group compared to 45.8% in the diffuse group (p = 0.400). Five patients (50%) from the segmental parenchymal thinning group underwent pyeloplasty in comparison to seven patients (70%) from the diffuse group (p = 0.430) Conclusion: There were no significant differences in renal function or rate of surgical intervention between neonates with segmental parenchymal thinning and diffuse parenchymal thinning. Neonates with segmental parenchymal thinning need to be monitored as closely as those with diffuse parenchymal thinning for early detection of renal deterioration and to identify potential need for surgical intervention.