Wei Ching Khor1, Suat Moi Puah1, Tse Hsien Koh2, Jin Ai Mary Anne Tan1, Savithiri D Puthucheary1,3, Kek Heng Chua1. 1. 1 Department of Biomedical Science, Faculty of Medicine, University of Malaya , Kuala Lumpur, Malaysia . 2. 2 Department of Microbiology, Singapore General Hospital , Singapore, Singapore . 3. 3 Department of Medical Microbiology, Faculty of Medicine, University of Malaya , Kuala Lumpur, Malaysia .
Abstract
OBJECTIVE: The objective of this study was to examine the species distribution, genetic relatedness, virulence gene profiles, antimicrobial sensitivities, and resistance gene distribution of clinical Aeromonas strains from Singapore and Malaysia. METHODS: A total of 210 Aeromonas clinical isolates were investigated: 116 from Singapore General Hospital and 94 archived clinical isolates from University of Malaya Medical Center, Malaysia. The isolates were genetically identified based on the gcat gene screening and the partial sequences of the rpoD housekeeping gene. Genetic relatedness, distribution of 15 virulence genes and 4 beta-lactamase resistance genes, and susceptibility patterns to 11 antimicrobial agents were compared. RESULTS: Of the 210 Aeromonas isolates, A. dhakensis-94 (45%) was the dominant species in Singapore and Malaysia. Species composition was similar and enterobacterial repetitive intergenic consensus-PCR did not show genetic relatedness between strains from the two countries. Of the 15 virulence genes, A. dhakensis and A. hydrophila harbored the most compared with other species. Different combinations of 9 virulence genes (exu, fla, lip, eno, alt, dam, hlyA, aexU, and ascV) were present in A. dhakensis, A. hydrophila, and A. veronii from both the countries. Distribution of virulence genes was species and anatomic site related. Majority (>80%) of the strains were susceptible to all antimicrobial agents tested, except amoxicillin and cephalothin. A. dhakensis strains from Malaysia significantly harbored the cphA gene compared with A. dhakensis from Singapore. Multidrug resistance was mostly detected in strains from peritoneal fluids of dialysis patients. CONCLUSION: This study revealed A. dhakensis as the dominant species isolated in both geographic regions, and that it carried a high number of virulence genes. It also highlights the geographic-related differences of virulence gene distribution and antimicrobial resistance profiles of clinical Aeromonas strains from Singapore and Malaysia.
OBJECTIVE: The objective of this study was to examine the species distribution, genetic relatedness, virulence gene profiles, antimicrobial sensitivities, and resistance gene distribution of clinical Aeromonas strains from Singapore and Malaysia. METHODS: A total of 210 Aeromonas clinical isolates were investigated: 116 from Singapore General Hospital and 94 archived clinical isolates from University of Malaya Medical Center, Malaysia. The isolates were genetically identified based on the gcat gene screening and the partial sequences of the rpoD housekeeping gene. Genetic relatedness, distribution of 15 virulence genes and 4 beta-lactamase resistance genes, and susceptibility patterns to 11 antimicrobial agents were compared. RESULTS: Of the 210 Aeromonas isolates, A. dhakensis-94 (45%) was the dominant species in Singapore and Malaysia. Species composition was similar and enterobacterial repetitive intergenic consensus-PCR did not show genetic relatedness between strains from the two countries. Of the 15 virulence genes, A. dhakensis and A. hydrophila harbored the most compared with other species. Different combinations of 9 virulence genes (exu, fla, lip, eno, alt, dam, hlyA, aexU, and ascV) were present in A. dhakensis, A. hydrophila, and A. veronii from both the countries. Distribution of virulence genes was species and anatomic site related. Majority (>80%) of the strains were susceptible to all antimicrobial agents tested, except amoxicillin and cephalothin. A. dhakensis strains from Malaysia significantly harbored the cphA gene compared with A. dhakensis from Singapore. Multidrug resistance was mostly detected in strains from peritoneal fluids of dialysis patients. CONCLUSION: This study revealed A. dhakensis as the dominant species isolated in both geographic regions, and that it carried a high number of virulence genes. It also highlights the geographic-related differences of virulence gene distribution and antimicrobial resistance profiles of clinical Aeromonas strains from Singapore and Malaysia.
Authors: Tien Tien Vicky Lau; Jin-Ai Mary Anne Tan; S D Puthucheary; Suat-Moi Puah; Kek-Heng Chua Journal: Braz J Microbiol Date: 2020-08-07 Impact factor: 2.476