Reduced graft survival in renal transplant patients with urinary tract infections - a meta-analysis

Renal transplant patients are prone to developing urinary tract infections (UTIs). However, the potential effect of a UTI on renal graft loss remains unclear.

We systematically surveyed the literature for a potential association between UTI and graft loss. Articles were identified in online databases using a specific search string, followed by post selection for meta-analysis following four inclusion criteria: 1) a clear definition of UTI and recurrent UTI, 2) n > 200, 3) patient age > 16 years and 4) inclusion of data on graft loss. Data on UTI and graft loss were extracted from the included studies for calculation of a combined weighted odds ratio (OR) using the Mantel-Haenszel method. This review was conducted according to the PRISMA 2020 statement.

Unfortunately, only eight of 108 papers met the inclusion criteria. These studies reported between 276 and 2,368 patients, primarily male, aged around 50 years. The two-year incidence of overall UTI varied from 16.5% at a 27.5-month follow-up to 30.1% at a 24-month follow-up from transplantation. Seven papers were included in the OR analysis; two found an association between UTI and graft loss and five did not. However, in the meta-analysis, the weighted OR for all seven studies was 1.340 (95% confidence interval: 1.050-1.720).

Filtering the literature for a strict definition of UTI allowed us to establish an association between UTI and graft loss in renal transplant patients. However, further investigation and stronger studies using the Goldman criteria are needed to allow stratification for UTI severity and effect on graft loss.