Does percutaneous drainage of malignant obstructive uropathy improve renal function? A retrospective records review

Abstract

Background: Malignant conditions of the pelvis and/or abdomen can cause ureteric obstruction and associated impaired renal function, which can be managed by performing percutaneous nephrostomy (PCN) tube insertion. This is often in a palliative setting and the available literature is still divided on the benefit that these procedures provide. The main objective of this study was to assess the changes in estimated glomerular filtration rate (eGFR) over the first six months following PCN for malignant ureteric obstruction. We also explored the role of urinary tract infections (UTIs) in the changes of eGFR following PCN.

Methods: Retrospective folder review of patients who had PCN procedures at Groote Schuur Hospital for malignant obstructive uropathy from January 2015 to December 2017. For each included patient, eGFR was recorded at baseline pre PCN, and at its best and worst value in the first six months after PCN, as well as the presence of confirmed UTIs.

Results: Fifty-four male and 36 female patients were included in the study, with a combined mean age of 56 years. The most common cancers in men were bladder (59%), while the most common cancers in women were cervix (64%). Pre-PCN eGFR, median (IQR), was 9 ml/min/1.73 m2 (5, 26). Post-PCN eGFR improved to 48 ml/min/1.73 m2 (30, 75) before deteriorating to 23 ml/min/1.73 m2 (9, 44) within the six-month follow-up window. The patients who developed UTI post PCN had 6.15 ml/min/1.73 m2 (95% CI: 0.87, 11.43) lower eGFR at their worst measurement.

Conclusion: Most patients’ renal function initially improved post-PCN, before deteriorating towards pre-PCN eGFR values within six months. Intercurrent UTIs are associated with a poor renal function response within six months post-PCN. These findings highlight the importance of shared decision making as to who will benefit from an intervention.