Epidemiology and emerging resistance in bacterial bloodstream infections in patients with hematologic malignancies

• Published in: Infectious diseases (London, England) England), 2015-01, Vol.47 (10), p.686-693
• Main Authors: Kara, Özgür, Zarakolu, Pinar, Aşçioğlu, Sibel, Etgül, Sezgin, Uz, Burak, Büyükaşik, Yahya, Akova, Murat
• Format: Article
• Language: English
• Subjects: Acinetobacter - drug effects; Acinetobacter - isolation & purification; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; antimicrobial resistance; bacteremia; Bacteremia - complications; Bacteremia - epidemiology; Bacteremia - microbiology; Bloodstream infection; Drug Resistance, Bacterial; Escherichia coli - isolation & purification; Female; Gram-Negative Bacteria - classification; Gram-Negative Bacteria - drug effects; Gram-Negative Bacteria - isolation & purification; Gram-Positive Bacteria - classification; Gram-Positive Bacteria - drug effects; Gram-Positive Bacteria - isolation & purification; hematologic malignancy; Hematologic Neoplasms - complications; Humans; Klebsiella - isolation & purification; Klebsiella - pathogenicity; Male; Microbial Sensitivity Tests; Middle Aged; neutropenia; Neutropenia - complications; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - isolation & purification; Staphylococcus aureus - isolation & purification; Tertiary Care Centers; Time Factors; Turkey - epidemiology; Young Adult
• ISSN: 2374-4235; 2374-4243
• DOI: 10.3109/23744235.2015.1051105

Background: The objective of this study was determine the frequency of bloodstream infections (BSIs) and the causative bacteria and their resistance patterns in patients with hematological malignancies (HMs) in a large tertiary care university hospital in Turkey over a 5-year period. Methods: A total of 2098 patients with HMs with 3703 neutropenic episodes were included. Patients were classified as high-risk (n = 843) and low-risk (n = 1255) groups and evaluated for frequency of BSIs, causative bacteria, and their resistance patterns. Results: The frequency of BSIs was 14.5%. The frequency of gram-negative BSIs in high-risk and low-risk groups was 10.7% and 5.4% (p < 0.001), respectively. The frequency of gram-positive BSIs in high-risk and low-risk groups was 7.0% and 3.9% (p < 0.001), respectively. Gram-negative bacteria predominated (52.6%), with Escherichia coli (17.3%) and Klebsiella spp. (11.0%) as the most frequent organisms. Coagulase-negative staphylococci (10.4%) and Corynebacterium spp. (6.3%) were the most common gram-positive bacteria (35.8%). The rate of extended-spectrum beta-lactamase (ESBL) production was 45% for E. coli and 58% for Klebsiella spp. Quinolone resistance was 58% for E. coli and 11% for Klebsiella spp.. The overall frequency of ceftazidime resistance in Pseudomonas aeruginosa was 28%, and 87% of Acinetobacter spp. were multidrug-resistant. Of Staphylococcus aureus isolates, 24.8% were resistant to methicillin. Conclusion: The dominating causes of BSIs in patients with HMs in our hospital are resistant gram-negative bacteria, which has made empirical antimicrobial choice a highly challenging issue in this patient population.