Phenotypic and Genotypic Investigation of Carbapenem-Resistant <i>Acinetobacter baumannii</i> in Maharaj Nakhon Si Thammarat Hospital, Thailand

Sirijan Santajit; Phuangthip Bhoopong; Thida Kong-Ngoen; Witawat Tunyong; Dararat Horpet; Wanfudhla Paehoh-ele; Tasneem Zahedeng; Pornpan Pumirat; Nitat Sookrung; Woranich Hinthong; Nitaya Indrawattana

doi:10.3390/antibiotics12030580

Antibiotics (Mar 2023)

Phenotypic and Genotypic Investigation of Carbapenem-Resistant <i>Acinetobacter baumannii</i> in Maharaj Nakhon Si Thammarat Hospital, Thailand

Sirijan Santajit,
Phuangthip Bhoopong,
Thida Kong-Ngoen,
Witawat Tunyong,
Dararat Horpet,
Wanfudhla Paehoh-ele,
Tasneem Zahedeng,
Pornpan Pumirat,
Nitat Sookrung,
Woranich Hinthong,
Nitaya Indrawattana

Affiliations

Sirijan Santajit: Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand
Phuangthip Bhoopong: Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand
Thida Kong-Ngoen: Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
Witawat Tunyong: Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
Dararat Horpet: Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand
Wanfudhla Paehoh-ele: Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand
Tasneem Zahedeng: Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand
Pornpan Pumirat: Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
Nitat Sookrung: Siriraj Center of Research Excellence in Allergy and Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
Woranich Hinthong: Princess Srisavangavadhana College of Medicine, Chulabhorn Royal Academy, Bangkok 10210, Thailand
Nitaya Indrawattana: Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand

DOI: https://doi.org/10.3390/antibiotics12030580
Journal volume & issue: Vol. 12, no. 3
p. 580

Abstract

Read online

(1) Background: Acinetobacter baumannii is well known as a causative agent of severe hospital-acquired infections, especially in intensive care units. The present study characterised the genetic traits of biofilm-forming carbapenem-resistant A. baumannii (CRAB) clinical isolates. Additionally, this study determined the prevalence of biofilm-producing A. baumannii isolates from a tertiary care hospital and investigated the association of biofilms with the distribution of biofilm-related and antibiotic resistance-associated genotypes. (2) Methods: The 995 non-duplicate A. baumannii isolates were identified, and their susceptibilities to different antibiotics were determined using the disk diffusion method. Using the modified microtiter plate assay, the CRAB isolates were investigated for their biofilm formation ability. Hemolysin and protease activities were determined. CRABs were subjected to polymerase chain reaction (PCR) assays targeting blaVIM, blaNDM, blaIMP, blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, csuE and pgaB genes. Individual CRAB isolates were identified for their DNA fingerprint by repetitive element sequence-based (REP)-PCR. (3) Results: Among all A. baumannii isolates, 172 CRABs were identified. The major antibiotic resistance gene among the CRAB isolates was blaOXA-51-like (100%). Ninety-nine isolates (57.56%) were biofilm producers. The most prevalent biofilm gene was pgaB (79.65%), followed by csuE (76.74%). Evidence of virulence phenotypes revealed that all CRAB exhibited proteolytic activity; however, only four isolates (2.33%) were positive for the hemolytic-producing phenotype. REP-PCR showed that 172 CRAB isolates can be divided into 36-DNA fingerprint patterns. (4) Conclusions: The predominance of biofilm-producing CRAB isolates identified in this study is concerning. The characterisation of risk factors could aid in controlling the continual selection and spreading of the A. baumannii phenotype in hospitals, thereby improving patient care quality.

Published in Antibiotics

ISSN: 2079-6382 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Medicine: Therapeutics. Pharmacology
Website: http://www.mdpi.com/journal/antibiotics

About the journal

Abstract

Keywords