A prospective multicenter study on the evaluation of antimicrobial resistance and molecular epidemiology of multidrug-resistant Acinetobacter baumannii infections in intensive care units with clinical and environmental features

Abstract

Background Multidrug-resistant (MDR) Acinetobacter baumannii infections are considered as emerging nosocomial infections particularly in patients hospitalized in intensive care units (ICUs). Therefore, reliable detection of MDR strains is crucial for management of treatment but also for epidemiological data collections. The purpose of this study was to compare antimicrobial resistance and the clonal distribution of MDR clinical and environmental A . baumannii isolates obtained from the ICUs of 10 different hospitals from five geographical regions of Turkey in the context of the demographic and clinical characteristics of the patients. Methods A multicenter-prospective study was conducted in 10 medical centers of Turkey over a 6 month period. A total of 164 clinical and 12 environmental MDR A. baumannii isolates were included in the study. Antimicrobial susceptibility testing was performed for amikacin (AN), ampicillin–sulbactam (SAM), ceftazidime (CAZ), ciprofloxacin (CIP), imipenem (IMP) and colistin (COL) by microdilution method and by antibiotic gradient test for tigecycline (TIG). Pulsed-field gel electrophoresis (PFGE) was performed to determine the clonal relationship between the isolates. The detection of the resistance genes, bla OXA-23 , bla OXA-24 , bla OXA-51, bla OXA-58, bla IMP, bla NDM , bla KPC , bla OXA-48 and bla PER-1 was carried out using the PCR method. Results The mortality rate of the 164 patients was 58.5%. The risk factors for mortality included diabetes mellitus, liv1er failure, the use of chemotherapy and previous use of quinolones. Antimicrobial resistance rates for AN, SAM, CAZ, CIP, IMP, COL and TIG were 91.8%, 99.4%, 99.4%, 100%, 99.4%, 1.2% and 1.7% respectively. Colistin showed the highest susceptibility rate. Four isolates did not grow on the culture and were excluded from the analyses. Of 172 isolates, 166 (96.5%) carried bla OXA-23 , 5 (2.9%) bla OXA-58 and one isolate (0.6%) was positive for both genes. The frequency of bla PER-1 was found to be 2.9%. None of the isolates had bla IMP , bla KPC , bla NDM and bla OXA-48 genes. PFGE analysis showed 88 pulsotypes. Fifteen isolates were clonally unrelated. One hundred fifty-seven (91.2%) of the isolates were involved in 14 diff...

Evaluating the antimicrobial resistance patterns and molecular frequency of blaoxa-48 and blaGES-2 genes in Pseudomonas aeruginosa and Acinetobacter baumannii strains isolated from burn wound infection in Tehran, Iran

“…These results were in contrast with those of Boral et al. [ 36 ] and Cheikh et al. [ 42 ] who reported that none of the A. baumannii isolates contained the bla oxa-48 gene.…”

“…Acinetobacter baumannii strains had a high level of resistance to all tested antibiotics, the results of which are in agreement with those obtained by Boral et al. [ 36 ], Azimi et al. [ 1 ], Romanin et al.…”

Antibiotic resistance assessment of Acinetobacter baumannii isolates from Tehran hospitals due to the presence of efflux pumps encoding genes (adeA and adeS genes) by molecular method

“…In a study by Boral et al [26], antibiotic resistance for Ciprofloxacin, Imipenem, Ampicillin/sulbactam, Ceftazidime, and Amikacin was observed to be 100%, 99.4%, 99.4%, 99.4%, and 91.8%, respectively. That is an increase in reported antibiotic resistance compared to the present study.…”

Çok İlaca Dirençli İnvaziv Acinetobacter baumannii İzolatlarında Biyofilm ve Biyofilm İlişkili Virülans Genlerinin Varlığı

“…Bu çalışmaya, Türkiye'nin farklı coğrafik bölgelerinde yer alan toplam 10 merkezden elde edilen ÇİD oldukları ve benzerlik durumları PFGE yöntemiyle daha önceden belirlenmiş invaziv A.baumannii izolatları (n= 156) dahil edildi 8 . Bu izolatlar kan, beyin omurilik sıvısı (BOS) ve özellikle cerrahi yoğun bakım ünitelerinde enfeksiyon tanısı ile tedavi edilen hastaların invaziv örneklerinden elde edildi.…”