Risk Factors and Outcome of Gram-Negative Bloodstream Infection in Living-Donor Renal Transplant Recipients: A Case-Control Study From Pakistan.

Abstract

Gram-negative rods are the most common cause of bloodstream infection in renal transplant recipients. Acute rejection, urologic abnormalities, and ureteral stents are risk factors. Graft dysfunction is independently associated with gram-negative rod bloodstream infection. Our aim is to investigate the incidence, risk factors, and outcome among living donor renal transplant recipients from Pakistan. In this case-control study, we reviewed the medical records until June 2021 of renal transplant recipients seen from 2015 to 2019 for gram negative bacteremia. For every case, controls were matched by age, date of transplant, and sex. Demographics, risk factors, graft function, and mortality were compared. Clinical features, immunosuppression, source of blood stream infection, and microbiology were noted in cases. Of 1677 renal transplant recipients, 44 developed gram negative bacteremia. The incidence was 5.9 per 1000 person-years. Median time since transplant was 5 months. The most common source was urinary tract infection. On univariate analysis, antithymocyte globulin, urinary tract infection, and recurrent urinary tract infections were associated with gram negative bacteremia. On multivariate analysis, urinary tract infection (adjusted odds ratio = 3.46; 95% CI, 1.27-9.37) and recurrent urinary tract infections (adjusted odds ratio = 4.03; 95% CI, 1.15-14.15) were significant risk factors. We found no difference in 30-day mortality and estimated glomerular filtration rate on last follow-up between cases and controls. Kaplan-Meier survival curves showed significant differences in graft survival in patients with gram negative bacteremia. Escherichia coli was the most common organism, with 75% ceftriaxone and 13% imipenem resistance. The most significant risk factor for gram negative rod bloodstream infection was recurrent urinary tract infections. Timely treatment and prevention of recurrent urinary tract infections areimperative for prevention of gram negative bacteremia.