Infection control management and surveillance of carbapenem-resistant Gram-negative bacteria in hematopoietic stem cell recipients

Hematopoietic stem cell transplantation (HSCT) is a curative treatment option for selected diseases of the hematopoietic system. In the context of HSCT, bloodstream infections caused by Gram-negative bacteria (GNB) significantly contribute to morbidity and mortality. Antibiotic treatment of bloodstream infections with carbapenem-resistant (CR) GNB presents a particular challenge. As a part of our infection control management, the admission of a patient who was known to be colonized with a CR Acinetobacter baumannii triggered an active weekly screening of all patients to determine the prevalence and potential transmission of CR GNB and CR Acinetobacter baumannii in particular. Over a 3 month period a total of 71 patients were regularly screened for colonization with CR GNB. Including the index patient, a total of three patients showed CR GNB colonization representing a prevalence of 4.2%. Nosocomial transmission of CR Acinetobacter baumannii or other CR GNB was not observed. However, the index patient developed a subsequent bloodstream infection with the CR Acinetobacter baumannii, therefore empiric antibiotic therapy based on the known resistance profile was initiated. A weekly prevalence screening for CR GNB might be an effective monitoring tool for potential transmission, may enhance existing infection control management concepts and may support the decision making for empiric antibiotic therapy.