Predictors of shock and mortality in solid organ transplant recipients with bacteremia caused by non-lactose-fermenting gram-negative bacilli

Abstract

Background: More data on bacteremia due to non-lactose fermenting gram-negative bacilli (NLF GNB) in solid organ transplant (SOT) recipients are needed. We aimed to investigate the epidemiology, microbiology, and risk factors for mortality and septic shock due to NLF GNB bacteremia in SOT recipients. Methods: We performed a retrospective, doublecenter study over a 12-year study period. The risk factors for mortality and septic shock in SOT recipients with NLF GNB bacteremia were assessed with multivariate logistic regression analysis. Results: A total of 230 episodes of bloodstream infections (BSIs) occurred in 159 SOT recipients. Fifty episodes of NLF GNB bacteremia were detected in 47 SOT recipients, with a predominance of Acinetobacter baumanii (27 isolates, 54.0%). The antibiotic resistance rate of all NLF GNB to 10 of 12 antibiotics investigated was more than 50%. The independent risk factors associated with septic shock were platelet count < 50 000/mm3 (odds ratio (OR) = 14.41, 95% confidence interval (CI) = 2.64 - 78.71, p = 0.002) and late-onset bacteremia (time of onset more than 2 months post-transplant) (OR = 10.87, 95% CI = 1.79 - 65.89, p = 0.009). Lung focus (OR = 32.91, 95% CI = 2.56 - 423.18, p = 0.007) and septic shock (OR = 70.38, 95% CI = 4.21 - 1176.21, p = 0.003) were risk factors for bacteremia-related mortality. Conclusions: The drug resistance of the pathogens and the morbidity and mortality rates of NLF GNB bacteremia were high in SOT recipients. For septic shock, associated risk factors were thrombocytopenia and late-onset bacteremia. The risk factors significantly associated with mortality were lung focus and septic shock.