Risk factors for mortality in patients with acute leukemia and bloodstream infections in the era of multiresistance

Objectives We assess the epidemiology and risk factors for mortality of bloodstream infection (BSI) in patients with acute leukemia (AL). Methods Prospectively collected data of a cohort study from July 2004 to February 2016. Multivariate analyses were performed. Results 589 episodes of BSI were documented in 357 AL patients, 55% caused by gram-positive bacteria (coagulase-negative staphylococci 35.7%, Enterococcus spp 10.8%) and 43.5% by gram-negative bacteria (E. coli 21%, PA 12%). We identified 110 (18.7%) multidrug-resistant (MDR) microorganisms, especially MDR-Pseudomonas aeruginosa (7%) and extended-spectrum beta-lactamase producing Enterobacteriaceae (7%). The 30-day mortality was 14.8%. Age (OR 3.1; 95% CI 1.7-5.7); chronic lung disease (4.8; 1.1-21.8); fatal prognosis according to McCabe index (13.9; 6.4-30.3); shock (3.8; 1.9-7.7); pulmonary infection (3.6; 1.3-9.9); and MDR-PA infections with inappropriate treatment (12.8; 4.1-40.5) were related to mortality. MDR-PA BSI was associated to prior antipseudomonal cephalosporin use (9.31; 4.38-19.79); current use of betalactams (2.01; 1.01-4.3); shock (2.63; 1.03-6.7) and pulmonary source of infection (9.6; 3.4-27.21). Conclusions MDR organisms were commonly isolated in BSI in AL. Inappropriate empiric antibiotic treatment for MDR-PA is the primary factor related to mortality that can be changed. New treatment strategies to improve the coverage of MDR-PA BSI should be considered in those patients with risk factors for this infection.