title: High prevalence of the PER-1 gene among carbapenem-resistant Acinetobacter baumannii in Riyadh, Saudi Arabia.
abstract: The prevalence of carbapenem-resistant Acinetobacter baumannii in Saudi Arabia and their resistance genetic mechanisms are yet to be identified. We studied the prevalence and genetic diversity of extended-spectrum beta-lactamase genes, particularly the PER-1 gene, among carbapenem-resistant A. baumannii strains from patients at a tertiary care hospital in Riyadh, Saudi Arabia between 2006 and 2014. Fresh subcultured samples were tested for antimicrobial susceptibility minimum inhibitory concentration (MIC). Total genomic DNA was extracted from each isolate and further used for polymerase chain reaction (PCR) genotyping, sequence-based typing (SBT) of PER-1 and OXA-51-like gene, and multilocus sequence typing (MLST) of positive isolates. Randomly selected clinical isolates (n = 100) were subjected to MLST. A total of 503 isolates were characterized as multidrug-resistant (MDR) using the MIC. Isolates were further PCR tested for bla-TEMand bla-PER-1resistance genes (n = 503). The genotyping results showed that 68/503 (14 %) isolates were positive to bla TEM. The genotyping results of PER-1-like genes showed that 384/503 (76.3 %) were positive among MDR Acinetobacter isolates. Based on SBT, the majority of these isolates were clustered into three main groups including isolates harboring PER-1: AB11 (bla-PER-1), isolate AB16 (bla-PER-1), and, finally, the plasmid pAB154 (bla-PER-7). Remarkably, many isolates were concealing the PER-1 gene and harboring the TEM resistance genes as well. MLST results for selected isolates (n = 100) identified four main sequence types (STs: 2, 19, 20, and 25) and four novel isolates (ST 486-489). We report 76.3 % prevalence of the PER-1 resistance gene among Acinetobacter clinical isolates from Riyadh, Saudi Arabia. Further work is needed to explore the clinical risks and patient outcome with such resistance related to healthcare-associated infections and investigate the genetic and molecular mechanisms that confer the MDR phenotype.
authors.affiliation: National Guard Health Affairs, King Abdullah International Medical Research Center (KAIMRC), P.O. Box 22490, Riyadh, 11426, Saudi Arabia. alyma@ngha.med.sa.|Department of Pathology, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia. alyma@ngha.med.sa.
authors.forename: M M
authors.initials: MM
authors.lastname: Aly
authors.affiliation: National Guard Health Affairs, King Abdullah International Medical Research Center (KAIMRC), P.O. Box 22490, Riyadh, 11426, Saudi Arabia.
authors.forename: N M
authors.initials: NM
authors.lastname: Abu Alsoud
authors.affiliation: Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia.|Biochemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
authors.forename: M S
authors.initials: MS
authors.lastname: Elrobh
authors.affiliation: Department of Pathology, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
authors.forename: S M
authors.initials: SM
authors.lastname: Al Johani
authors.affiliation: National Guard Health Affairs, King Abdullah International Medical Research Center (KAIMRC), P.O. Box 22490, Riyadh, 11426, Saudi Arabia.|Department of Infection Prevention and Control, King Abdulaziz Medical City, Riyadh, Saudi Arabia.|Department of Pediatrics, King Abdulaziz Medical City, Riyadh, Saudi Arabia.
authors.forename: H H
authors.initials: HH
authors.lastname: Balkhy
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D010957:Plasmids / Q000032:analysis; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012529:Saudi Arabia / Q000453:epidemiology; D017422:Sequence Analysis, DNA; D062606:Tertiary Care Centers; D055815:Young Adult; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000032:analysis* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D004269:DNA, Bacterial; C108863:beta-lactamase PER-1; D001618:beta-Lactamases