Contamination of perfusion fluid and its impact on kidney transplantation: an observational study from a single Brazilian center.

Infections represent a major cause of morbidity and mortality in kidney transplant recipients. Preservation fluid (PF) contamination is considered a potential infectious source; however, its clinical relevance remains controversial. To evaluate whether PF contamination acts as a source of early post-transplant infections (within 30 days) and its association with acute rejection, graft loss, and mortality within 90 days. This was a retrospective, observational, and descriptive study based on medical records of patients aged ≥18 years who underwent kidney transplantation between January 2021 and December 2023. Collected variables included demographic, clinical, and post-transplant outcome data. Among 246 recipients with available PF culture data, 27.6% (68/246) presented with PF contamination. Gram-positive cocci accounted for 64.7% of isolates, Gram-negative bacilli, for 35.3%, and fungi, for 2.9%. Coagulase-negative staphylococci (CoNS) were the most frequent isolate (36.8%). Microbiological concordance between PF isolates and pathogens responsible for early infection were observed in 13.23% (9/68) of cases, with Klebsiella pneumoniae being the predominant pathogen (66.6%). Although the infection rate was higher among patients with positive PF cultures (72%) compared to those with negative cultures (64%), this difference was not statistically significant (p = 0.2992). No significant associations were found with mortality (p = 1.000), graft loss (p = 0.8199), or acute rejection (p = 0.5635). PF contamination was frequent and may contribute to early post-transplant infections, reinforcing the importance of microbiological surveillance and preventive strategies.