Extended-spectrum beta-lactamase-producing bacteria isolated from hematologic patients in Manaus, State of Amazonas, Brazil

Abstract

Antibiotic therapy in hematologic patients, often weak and susceptible to a wide range of infections, particularly nosocomial infections derived from long hospitalization periods, is a challenging issue. This paper presents ESBL-producing strains isolated from such hematologic patients treated at the Amazon Hematology and Hemotherapy Foundation (HEMOAM) in the Brazilian Amazon Region to identify the ESBL genes carried by them as well as the susceptibility to 11 antimicrobial agents using the E-test method. A total of 146 clinical samples were obtained from July 2007 to August 2008, when 17 gram-negative strains were isolated in our institution. The most frequent isolates confirmed by biochemical tests and 16S rRNA sequencing were E. coli (8/17), Serratia spp. (3/17) and B.cepacia (2/17). All gram-negative strains were tested for extended-spectrum-beta-lactamases (ESBLs), where: (12/17) strains carried ESBL; among these, (8/12) isolates carried blaTEM, blaCTX-M, blaOXA, blaSHV genes, (1/12) blaTEM gene and (3/12) blaTEM, blaCTX-M, blaOXA genes. Antibiotic resistance was found in (15/17) of the isolates for tetracycline, (12/17) for ciprofloxacin, (1/17) resistance for cefoxitin and chloramphenicol, (1/17) for amikacin and (3/17) cefepime. This research showed the presence of gram-negative ESBL-producing bacteria infecting hematologic patients in HEMOAM. These strains carried the blaTEM, blaSHV, blaCTX-M and blaOXA genes and were resistant to different antibiotics used in the treatment. This finding was based on a period of 13 months, during which clinical samples from specific populations were obtained. Therefore, caution is required when generalizing the results that must be based on posological orientations and new breakpoints for disk diffusion and microdilution published by CLSI 2010

The First Report of Extended-Spectrum β-Lactamase (ESBL) Genes in an Escherichia coli Isolate from a One-Month-Old Infant with Acute Lymphoblastic Leukemia (ALL) in Iran

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Prevalence and Characterization of Extended Spectrum Beta-Lactamase Production in Clinical Isolates of Klebsiella pneumonia

“…Reported frequency of ESBL producing Klebsiella species in India ranged from 14-100% [16,19]. Prevalence of ESBL producing Klebsiella around the world varies between 3%-8% to 100% [35,45]. The easiest approach to genetic detection of β-lactamases is the amplification of the whole β-lactamase (bla) gene or its parts using PCR with oligonucleotide primers that are specific for the target gene.…”

Extended spectrum beta-lactamase production and plasmid mediated quinolone resistance among lactose non-fermenting nterobacteriaceae isolated from poultry sources in Calabar, Nigeria

“…The quality control strain used was E. coli ATTC 25922. The susceptibility of the isolates to the antimicrobial agents was determined by means of the Kirby-Bauer disk diffusion method as described by the Clinical and Laboratory Standard Institute (Ferreira et al, 2011) Transferring 4 to 5 confirmed Salmonella colonies in a tube containing 2.5 ml sterile normal saline by means of a sterile inoculating loop to prepare a bacterial lawn. The suspension was vortexed and its turbidity compared with barium chloride (0.5 McFarland Turbidity Standard; 1.0 × 10 8 CFU/µL).…”