High Frequencies of Drug-resistant Pathogens in Blood Stream Infections Associated with Hematologic Disorders: Five-year single institutional surveillance from 2010 to 2014

Abstract

In order to improve the management of infectious complications associated with hematologic disorders, we conducted a retrospective 5-year analysis of Blood Culture (BC) tests obtained from febrile patients with hematological disorders treated in our institute between 2010 and 2014. BCs were performed using the BacT/ALERT 3D system (bioMérieux, Marcy l'Etoile, France) and identification and antibiotic susceptibility testing were performed using VITEK2 (bioMérieux). In 8,549 BC tests obtained from 1,517 febrile events, 325 BC tests showed positive results in 154 febrile episodes with 91 patients. In BC-positive episodes, the incidence of BC-positivity for 3 consecutive BC tests per febrile episode was 98.1 %. The frequencies of Gram-positive and Gram-negative bacteria as the causative pathogen were almost equal (44.5 % vs 43.3 %). The frequency of drug-resistant bacteria, such as either methicillin-resistant cocci or extended spectrum beta-lactamase producing organism, was more than 50 %. The use of a central venous catheter showed a positive relationship with the methicillin-resistant cocci in our series. Our study found increasing frequencies of drug-resistant bacteria as the pathogens of blood stream infection in hematological disorders. These results are instructive for the appropriate selection of empiric antibiotic therapy for febrile events in patients with hematologic malignancies.