Article

Bacteremia due to extended-spectrum-β-lactamase-producing Aeromonas spp. at a medical center in Southern Taiwan.

Department of Internal Medicine, National Cheng Kung University Medical College and Hospital, Tainan, Taiwan.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.57). 10/2011; 55(12):5813-8. DOI: 10.1128/AAC.00634-11
Source: PubMed

ABSTRACT Although extended-spectrum-β-lactamase (ESBL)-producing aeromonads have been increasingly reported in recent years, most of them were isolates from case reports or environmental isolates. To investigate the prevalence of ESBL producers among Aeromonas blood isolates and the genes encoding ESBLs, consecutive nonduplicate Aeromonas blood isolates collected at a medical center in southern Taiwan from March 2004 to December 2008 were studied. The ESBL phenotypes were examined by clavulanate combination disk test and the cefepime-clavulanate ESBL Etest. The presence of ESBL-encoding genes, including bla(TEM), bla(PER), bla(CTX-M), and bla(SHV) genes, was evaluated by PCR and sequence analysis. The results showed that 4 (2.6%) of 156 Aeromonas blood isolates, 1 Aeromonas hydrophila isolate and 3 Aeromonas caviae isolates, expressed an ESBL-producing phenotype. The ESBL gene in two A. caviae isolates was bla(PER-3), which was located in both chromosomes and plasmids, as demonstrated by Southern hybridization. Of four patients with ESBL-producing Aeromonas bacteremia, two presented with catheter-related phlebitis and the other two with primary bacteremia. Three patients had been treated with initial noncarbapenem β-lactams for 5 to 10 days, and all survived. In conclusion, ESBL producers exist among Aeromonas blood isolates, and clinical suspicion of ESBL production should be raised in treating infections due to cefotaxime-resistant Aeromonas isolates.

0 Bookmarks
 · 
164 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Salmonella spp. infections are considered as the most common food-borne disease globally. The contamination of food products with Salmonella has given rise to severe health and economic challenges. This study assessed the prevalence of Salmonella in the faeces of cows and goats in the Eastern Cape province of South Africa, their antibiotic resistance patterns as well as antibiotic-resistant gene determinant. Antibiotic disc was used for antibiogram profiles while polymerase chain reaction was employed for the detection of antibiotic-resistant genes. A total of 150 Salmonella were isolated from the faecal samples. Eighty two (55 %) isolates were recovered from cow faeces while 68 (45 %) were isolated from goat faeces. All Salmonella isolates were sensitive to ciprofloxacin (100 %) while 95 % were sensitive to ofloxacin. Also, a high sensitivity of 93 and 89 % was observed against nalidixic acid and ofloxacin, respectively. Salmonella isolates demonstrated moderate sensitivity against cephalothin (70 %), chloramphenicol (75 %) and minocycline (68 %) while 49 % were resistant to tetracycline and erythromycin. The prevalence of the antibiotic-resistant genes in Salmonella isolates were detected as follows: integron conserved segment 28 % (42/150), bla TEM gene 19.3 % (29/150), bla pse1 7.3 % (11/150) and bla amp C 4.7 % (7/150). The results obtained in the study imply that cow and goat faeces could be potential reservoirs of Salmonella and could possibly cause infections as a result of contamination of food products. There is a need for a surveillance system to track resistance patterns of Salmonella circulating in South Africa.
    Tropical Animal Health and Production 10/2014; · 0.97 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aeromonas dhakensis, often phenotypically identified as A. hydrophila, is an important human pathogen. The present study aimed to compare the clinical and biological features of A. dhakensis and A. hydrophila isolates from human wounds. A total of 80 of Aeromonas wound isolates collected between January 2004 and April 2011 were analyzed. The species was identified by the DNA sequence matching of rpoD and gyrB (or rpoB if necessary). Most of the Aeromonas isolates were identified as A. dhakensis (37, 46.3%), and 13 (16.3%) as A. hydrophila. Both these two species alone can cause severe skin and soft-tissue infections. More A. dhakensis isolates were found in wounds exposed to environmental water (32.4% vs. 0%, P=0.042). More biofilm formation was noted among A. dhakensis isolates (mean OD570 , 1.23±0.09 vs. 0.78±0.21, P=0.03). The minimal inhibitory concentrations of ceftriaxone, imipenem, and gentamicin for A. dhakensis isolates were higher (P values <0.0001, 0.04, and 0.01, respectively). The survival rates of Caenorhabditis elegans co-incubated by A. dhakensis from day 1 to day 3 were lower than those of worms infected with A. hydrophila in liquid toxicity assays (all P values <0.01). A. dhakensis isolates exhibited more cytotoxicity, as measured by the released leukocyte lactate dehydrogenase levels in human normal skin fibroblast cell lines (29.6±1.2% vs. 20.6±0.6%, P<0.0001). The cytotoxin gene ast was primarily present in A. hydrophila isolates (100% vs. 2.7%, P<0.0001). In summary, A. dhakensis is the predominant species among Aeromonas wound isolates, and more virulent than A. hydrophila. This article is protected by copyright. All rights reserved.
    Clinical Microbiology and Infection 11/2013; · 4.58 Impact Factor
  • Source
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 04/2014; · 3.22 Impact Factor

Full-text (2 Sources)

Download
40 Downloads
Available from
May 21, 2014