Antibiogram, Prevalence of OXA Carbapenemase Encoding Genes, and RAPD-Genotyping of Multidrug-Resistant Acinetobacter baumannii Incriminated in Hidden Community-Acquired Infections

Abstract

Acinetobacter spp. has gained fame from their ability to resist difficult conditions and their constant development of antimicrobial resistance. This study aimed to investigate the prevalence, susceptibility testing, OXA carbapenemase-encoding genes, and RAPD-genotyping of multidrug resistant Acinetobacter baumannii incriminated in hidden community-acquired infections in Egypt. The antimicrobial susceptibility testing was assessed phenotypically using Kirby–Bauer disk diffusion method. Also, Modified-Hodge test (MHT) was carried out to detect the carbapenemases production. Multiplex-PCR was used to detect the carbapenemase-encoding genes. Furthermore, the genetic relationship among the isolated strains was investigated using RAPD fingerprinting. The bacteriological examination revealed that, out of 200 Gram-negative non-fermentative isolates, 44 (22%) were identified phenotypically and biochemically as Acinetobacter spp. and 23 (11.5%) were molecularly confirmed as A.baumannii. The retrieved A.baumannii strains were isolated from urine (69%), sputum (22%), and cerebrospinal fluid (csf) (9%). The isolated A. baumannii strains exhibited multidrug resistance and the production rates of carbapenemases were 56.5, 60.9, and 78.3% with meropenem, imipenem, and ertapenem disks, respectively. The blaOXA-24-like genes were the most predominant among the tested strains (65.2%), followed by blaOXA-23 (30.4%) and blaOXA-58 (17.4%), in addition, the examined strains are harbored IMP, VIM, and NDM genes with prevalence of 60.9, 43.5, and 13%, respectively, while KPC and GES genes were not detected. RAPD-PCR revealed that the examined strains are clustered into 11 different genotypes at ≥90% similarity. Briefly, to the best of our knowledge, this study is the first report concerning community-associated A. baumannii infections in Egypt. The high prevalence of hidden multidrug-resistant (MDR) and extensively drug-resistant (XDR) A.baumannii strains associated with non-hospitalized patients raises an alarm for healthcare authorities to set strict standards to control the spread of such pathogens with high rates of morbidity and mortality.

Molecular Epidemiology of Extensively-Drug Resistant Acinetobacter baumannii Sequence Type 2 Co-Harboring blaNDM and blaOXA From Clinical Origin

“… 22 In this study, the intrinsic bla OXA-51 was detected in all A. baumannii isolates, stressing the importance of using the bla OXA-51 gene as an alternative marker for Acinetobacter spp ., identification, as described previously. 23 , 24 A. baumannii is considered among the major nosocomial pathogens and has been identified in various areas of the hospital environment, including on medical devices and intravenous catheters. 25 In the present study, A. baumannii were recovered from numerous clinical specimens, primarily from sputum (46%) and pus (24%) samples, and were prevalent among patients admitted to the ICU (75%).…”

Genomic and phenotypic analyses of diverse non-clinical Acinetobacter baumannii strains reveals strain-specific virulence and resistance capacity

“…However, detection of community-acquired A. baumannii infections with high rates of morbidity and mortality in a number of countries [10–16] has prompted research on the virulence potential and molecular traits of non-clinical environmental strains. Unlike the majority of nosocomial strains, community-acquired infections tend to be more susceptible to antimicrobials [11, 17] and epidemiologically more closely related to strains recovered from environmental sources [11].…”

Antibacterial Effects of Octenidine Dihydrochloride, and Benzalkanium Chloride on Acinetobacter Baumannii Strains Isolated from Clinical Samples and Determination of Genetic Diversity of Isolates by RAPD-PCR Method

“…Concentration of recent clinical consideration has been on the increasing rate of lactose non-fermenting, gram-negative bacteria leading to infections in health care settings. Nowadays, Acinetobacter species are rising as pathogens that sometimes cause infections in patients in ICU [21]. In our study, most isolates of A. baumannii (52.10%) were obtained from patients in ICU.…”