Molecular Typing of Multidrug-Resistant Acinetobacter baumannii Isolates from Clinical Specimens by ERIC-PCR and MLVA

• Published in: Current microbiology 2023-11, Vol.80 (11), p.355-355, Article 355
• Main Authors: Osanloo, Leili, Zeighami, Habib, Haghi, Fakhri, Shapouri, Reza, Shokri, Rasoul
• Format: Article
• Language: English
• Subjects: Acinetobacter baumannii; Aminoglycoside antibiotics; Aminoglycosides; Antibiotic resistance; Antibiotics; Biomedical and Life Sciences; Biotechnology; Clusters; Diffusion tests; Drug resistance; Genotyping; Immunocompromised hosts; Life Sciences; Microbiology; Multidrug resistance; Multidrug resistant organisms; Nosocomial infection; Patients; Polymerase chain reaction
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-023-03459-x

Acinetobacter baumannii , a Gram-negative and oxidase-negative bacterium, is a major cause of nosocomial infections, leading to high mortality rates in hospitalized patients. The use of 2 prominent molecular typing methods (i.e., enterobacterial repetitive intergenic consensus–polymerase chain reaction [ERIC-PCR] and multiple-locus variable-number tandem repeat [VNTR] analysis [MLVA]) for genotyping A. baumannii isolates has proven to be an effective approach in assessing the clonal relation of these isolates and managing their outbreaks. A total of 100 A. baumannii isolates were collected from immunocompromised patients hospitalized in the intensive care unit (ICU) of a hospital in Zanjan City, Iran. Their antibiotic resistance ability (especially aminoglycoside resistance) was studied by disc diffusion tests. The genetic typing of A. baumannii was studied using ERIC-PCR and MLVA methods. All isolates were resistant to 3 or more antibiotics and regarded as multidrug-resistant (MDR). Additionally, 32% of the isolates were resistant to all antibiotics tested, and 91% were extensively drug-resistant (XDR). The increased rate of aminoglycoside-resistant A. baumannii in ICU patients, with an increased incidence of aminoglycoside-modifying enzymes of aac (6′)-Ib, ant (3″)-I, and aph (2″)-Id . ERIC-PCR has likewise shown an increased level of diversity in A. baumannii isolates. According to the ERIC-PCR patterns, isolates were classified as 4 clusters, while according to the MLVA patterns, isolates were classified as 9 distinct clusters. ERIC-PCR and MLVA assays serve as useful genotyping methods to assess the genetic variety or clonal relatedness of A. baumannii isolates.