National Study Reveals Gram Negative Bacteremia on Contemporary Pediatric AML Protocol

Abstract

Abstract Background Bacteremia complicates more than 50% of childhood Acute myeloid leukemia (AML) patients with predominantly Gram-positive cocci )GPC). Objectives Assess bacteremia rates, risk factors, causative organisms, and antibiotic resistance in Israeli children with de-novo AML. Methods all chemotherapy courses for patients enrolled in the standard arm of the NOPHO-DBH 2012 AML protocol were included. Down syndrome, myelodysplastic syndrome, acute promyelocytic leukemia, secondary AML, and isolated granulocytic sarcoma were excluded. No routine antibacterial prophylaxis was applied. Results Among 69 patients, 7 had focal bacterial infections. Of the remaining 62, 77.4% had bacteremia episodes, ranging from 1 to 8 per patient. Out of 238 chemotherapy courses, 98 (41.2%) resulted in bacteremia, with 66 (67.3%) courses showing predominantly Gram-negative rods (GNR) and 28 (28.6%) courses with Gram-positive cocci (GPC). The most common was Escherichia coli; followed by Klebsiella spp. Older age, Arab ethnicity, and presenting white blood cell count were associated with an increased risk of bacteremia in a univariate analysis. Six patients (9.7%) died, 3 of whom were from Gram-negative infection. Bacteremia resulted in a 7-fold increase in intensive care unit admissions. Empiric antibiotic treatment using piperacillin-tazobactam and vancomycin provided sufficient coverage in 75.5% of cases. Improved coverage was attained with amikacin (90.8%) or the combination of vancomycin and meropenem (94.7%). Quinolones were effective against GNR isolates in 42 cases (61.8%). Conclusions De-novo AML patients face high mortality from predominantly GNR bacteremia. Specific interventions are needed to reduce rates, but limited susceptibility to quinolones hampers prophylactic use.