Non-fermentative Gram-negative rods bacteremia in children with cancer: a 14-year single-center experience

Data on non-fermentative Gram-negative rods (NFGNR) bacteremia in children with malignancies are limited. The aim of this study was to present clinical picture, antimicrobial susceptibility pattern, risk factors for resistance and outcome in NFGNR bacteremia in children with cancer. All episodes of NFGNR bacteremia occurring during 2001-2014 in children with cancer in a tertiary-care hospital were retrospectively analyzed. Pseudomonas and Acinetobacter spp. resistant to three or more antibiotic classes and all Stenotrophomonas maltophilia (SM) were defined as multidrug-resistant bacteria (MDR). A total of 80 children (44 males, 0.8-18 years, median 5 years) developed 107 episodes (116 pathogens) of NFGNR bacteremia; Pseudomonas aeruginosa (PA) (51; 43.9%), Acinetobacter baumannii (AB) (21, 18.1%), SM (18, 15.5%); and others (27, 25.2%). The rate of NFGNR bacteremia in children with certain solid tumors (e.g. sarcoma, 12/134 (9.0%)) was comparable to that of hematological malignancies (52/429 (12.2%). Focal infection and septic shock occurred in 16 (14.9%) and four (3.7%) episodes, respectively. Thirty (25.8%) of 116 NFGNR were MDR. The most significant predictors of bacteremia with MDR PA or AB were severe neutropenia (< 100 cells/mm(3); OR 7.8, p = 0.002), hospital-acquired (OR 16.9, p < 0.0001) and breakthrough (OR 11.2, p < 0.0001) infection. Infection with MDR bacteria was associated with inappropriate empirical therapy. The 30-day mortality was 3/107 (2.8%), all in neutropenic patients with hematological malignancies. NFGNR bacteremia can present with nonspecific signs or symptoms. MDR NFGNRs are common and compromise treatment options, but mortality is relatively low. Knowledge of local epidemiology, pattern and risk factors for resistance is important to guide empirical therapy.