Introduction

Lower urinary tract obstruction (LUTO) is associated with impairment of kidney and bladder function, leading to adverse long-term outcomes. Early proactive management with timely urinary diversion, if necessary, is important, especially after failed initial ablation. This study aims to explore the impact of secondary diversion compared to primary diversion on kidney and bladder function in infants with LUTO.

Methods

After retrospective review of a LUTO database between 1999 to 2022, 51 patients with primary or secondary diversion were captured. Primary outcomes included creatinine values, end-stage renal disease (ESRD), degree of urinary tract dilatation, need for renal replacement therapy and use of clean intermittent catheterization (CIC). Comparative statistics are shown as mean + standard deviation (SD).

Results

A total of 51 patients receiving primary (n=37) or secondary diversion (n=14) with a postoperative mean follow-up of 5.6 + 5.1 years demonstrated. Comparable creatinine levels were reported preoperatively (p=0.1141), 30 days (p=0.4529) and 1 year postoperatively (p=0.4712). There were no differences in creatinine at 1 year of age (p=0.2573), time to nadir (p=0.0788) and nadir creatinine levels (p=0.3069) between both groups. Secondary diversion was associated with older ages at nadir creatinine (p=0.0255), closure of diversion (p=0.0434) and persistent high-grade hydronephrosis (HN, p=0.0109) at last follow-up. Likelihood of ESRD (p=0.2717), CIC (p=0.1665) and UTI rates (p=0.2069) were not impacted by delayed diversion.

Conclusion

Comparison of outcomes for primary and secondary diversion in LUTO patients suggests no impairment in short-term renal function. Although early diversion should be preferred with regard to long-term kidney function, these results demonstrate that secondary diversion can still have a positive impact on short-term outcomes. 

However, long-term follow-up data are required to assess if the persistence of high-grade HN in the majority of patients with secondary diversion is ultimately associated with an impairment of kidney function at later ages raising the need for earlier and more proactive management in these infants.