Bacteremia During the First Year After Solid Organ Transplantation: An Epidemiological Update
Authors: Neofytos Dionysios , Stampf Susanne , Hoessly Linard D , D’Asaro Matilde , Tang Gael Nguyen , Boggian Katia , Hirzel Cedric , Khanna Nina , Manuel Oriol , Mueller Nicolas J , Van Delden Christian ,   for the Swiss Transplant Cohort Study, Amico Patrizia , Aubert John-David , Banz Vanessa , Beckmann Sonja , Beldi Guido , Berger Christoph , Berishvili Ekaterine , Berzigotti Annalisa , Binet Isabelle , Bochud Pierre-Yves , Branca Sanda , Bucher Heiner , Carrel Thierry , Catana Emmanuelle , Cairoli Anne , Chalandon Yves , De Geest Sabina , De Seigneux Sophie , Dickenmann Michael , Dreifuss Joëlle Lynn , Duchosal Michel , Fehr Thomas , Ferrari-Lacraz Sylvie , Frossard Jaromil , Garzoni Christian , Golshayan Déla , Goossens Nicolas , Haidar Fadi , Halter Jörg , Heim Dominik , Hess Christoph , Hillinger Sven , Hirsch Hans , Hirt Patricia , Hofbauer Günther , Hoessly Linard , Huynh-Do Uyen , Immer Franz , Koller Michael , Laesser Bettina , Lamoth Frédéric , Lehmann Roger , Leichtle Alexander , Manuel Oriol , Marti Hans-Peter , Martinelli Michele , McLin Valérie , Mellac Katell , Merçay Aurélia , Mettler Karin , Müller Nicolas , Müller-Arndt Ulrike , Müllhaupt Beat , Nägeli Mirjam , Oldani Graziano , Pascual Manuel , Passweg Jakob , Pazeller Rosemarie , Posfay-Barbe Klara , Rick Juliane , Rosselet Anne , Rossi Simona , Rothlin Silvia , Ruschitzka Frank , Schachtner Thomas , Schaub Stefan , Scherrer Alexandra , Schneidawind Dominik , Schnyder Aurelia , Schuurmans Macé , Schwab Simon , Sengstag Thierry , Simonetta Federico , Steiger Jürg , Stirnimann Guido , Stürzinger Ueli , Van Delden Christian , Venetz Jean-Pierre , Villard Jean , Vionnet Julien , Wick Madeleine , Wilhelm Markus , Yerly Patrick 
Published: May 2023

Abstract

Background
There are limited contemporary data on the epidemiology and outcomes of bacteremia in solid organ transplant recipients (SOTr).

Methods
Using the Swiss Transplant Cohort Study registry from 2008 to 2019, we performed a retrospective nested multicenter cohort study to describe the epidemiology of bacteremia in SOTr during the first year post-transplant.

Results
Of 4383 patients, 415 (9.5%) with 557 cases of bacteremia due to 627 pathogens were identified. One-year incidence was 9.5%, 12.8%, 11.4%, 9.8%, 8.3%, and 5.9% for all, heart, liver, lung, kidney, and kidney-pancreas SOTr, respectively (P = .003). Incidence decreased during the study period (hazard ratio, 0.66; P &lt; .001). One-year incidence due to gram-negative bacilli (GNB), gram-positive cocci (GPC), and gram-positive bacilli (GPB) was 5.62%, 2.81%, and 0.23%, respectively. Seven (of 28, 25%) Staphylococcus aureus isolates were methicillin-resistant, 2/67 (3%) enterococci were vancomycin-resistant, and 32/250 (12.8%) GNB produced extended-spectrum beta-lactamases. Risk factors for bacteremia within 1 year post-transplant included age, diabetes, cardiopulmonary diseases, surgical/medical post-transplant complications, rejection, and fungal infections. Predictors for bacteremia during the first 30 days post-transplant included surgical post-transplant complications, rejection, deceased donor, and liver and lung transplantation. Transplantation in 2014–2019, CMV donor-negative/recipient-negative serology, and cotrimoxazole Pneumocystis prophylaxis were protective against bacteremia. Thirty-day mortality in SOTr with bacteremia was 3% and did not differ by SOT type.

Conclusions
Almost 1/10 SOTr may develop bacteremia during the first year post-transplant associated with low mortality. Lower bacteremia rates have been observed since 2014 and in patients receiving cotrimoxazole prophylaxis. Variabilities in incidence, timing, and pathogen of bacteremia across different SOT types may be used to tailor prophylactic and clinical approaches.