Evaluation of sulbactam and colistin/sulbactam efficacy against multiple resistant Acinetobacter baumannii blood isolates.

Indian J Med Microbiol

Suleyman Demirel University, Faculty of Pharmacy, Pharmaceutical Microbiology, Isparta, Turkey. Electronic address:

Published: October 2022

Purpose: We aimed to compare the results of the BD Phoenix (TM) M50 ID/AST system and the gold standard broth microdilution method. We also evaluated the potential of a new therapeutic combination (colistin/sulbactam) for colistin resistance among Acinetobacter baumanni strains.

Methods: Growth in blood samples was detected with the BACTEC (BD Becton Dickinson, ABD) continuous monitoring blood culture system. Strains were identified by Phoenix (BD Phoenix™ M50, ABD) automated bacterial identification system and antimicrobial susceptibility results were obtained. A total of 92 A. baumannii complex isolates showing resistance to at least three antibiotic classes were included in the study. Colistin susceptibility results (both susceptible and resistant strains) detected by the Phoenix device were confirmed by the reference method, the liquid microdilution method. The concentration index (FIC) was used to determine the efficacy of fractional inhibitor drug combinations, the efficacy of colistin/sulbactam combination against 50 multiresistant A. baumannii complex strains was investigated using the checkerboard method.

Results: 10 (10.9%) of 92 isolates were resistant to colistin and 80 (86.9%) to sulbactam. With the automation system, only 2 of 10 isolates were found resistant to colistin, while 8 isolates were susceptible. For this reason, the very major error rate of the Phoenix M50 automatic system among resistant isolates was determined as 8/10. It was determined that 6 (12%) of the colistin/sulbactam combination had a synergistic effect and 44 (88%) had an additive interaction. No antagonistic interaction was detected with the colistin-sulbactam combination in this study.

Conclusion: A. baumannii strains should be confirmed by the broth microdilution method, which is the reference method, against the MIC results detected by automated systems. It was concluded that the use of colistin alone should be avoided in the treatment of A. baumannii infections.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijmmb.2022.06.009DOI Listing

Publication Analysis

Top Keywords

microdilution method
12
phoenix m50
8
broth microdilution
8
a baumannii complex
8
reference method
8
colistin/sulbactam combination
8
isolates resistant
8
resistant colistin
8
isolates
6
resistant
5

Similar Publications

Background: The occurrence of Stenotrophomonas maltophilia infections, especially pneumonia, has increased consistently in the last years. We evaluated the antimicrobial susceptibility of a large collection of S. maltophilia collected in Europe, Asia, and Latin America.

View Article and Find Full Text PDF

<b>Background and Objective:</b> <i>Oroxylum indicum</i>, a plant commonly used in traditional medicine to address various human ailments, has recently gained attention as a promising candidate in this regard due to its rich phytochemical composition and potential antibacterial properties. This study was undertaken to evaluate the antibacterial efficacy of <i>O. indicum</i> extracts, specifically from its leaves and stems, against antibiotic-resistant bacteria.

View Article and Find Full Text PDF

In-vitro susceptibility of pathogenic and intermediate Leptospira species towards antibiotics and herb extracts.

Trop Biomed

December 2024

Resource Biotechnology Programme, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Sarawak, Malaysia.

Leptospirosis is a severe and potentially fatal re-emerging zoonotic and waterborne disease caused by pathogenic and intermediate species of Leptospira. Given the high global rates of morbidity and mortality associated with this disease, there is an urgent need to explore alternative therapeutic agents to enhance treatment options. This study investigates the anti-leptospiral efficacy of several common antibiotics-penicillin G, doxycycline, ampicillin, amoxicillin, cefotaxime, chloramphenicol, and erythromycin, as well as extracts from local herbs, Hydnophytum formicarum Jack and Boesenbergia stenophylla, against pathogenic and intermediate Leptospira strains.

View Article and Find Full Text PDF

Epidemiology of colistin resistance mediated by mcr-1 in carbapenemase-producing Enterobacterales in Ecuador in three periods from 2016 to 2022.

Rev Argent Microbiol

January 2025

Department of Microbiology, School of Medicine and PhD Program in Clinical Medicine and Public Health, University of Granada & Ibs, Granada, Spain; Department of Microbiology, Hospital Virgen de las Nieves, Institute for Biosanitary Research-Ibs, Granada, Spain.

Carbapenemase-producing Enterobacterales (CPE) have increased in the last decade. In low-income countries, colistin is considered a last resort antimicrobial to treat CPE infections, whose most worrisome mechanism of resistance is MCR-1 production. This study aims to understand the epidemiology of colistin resistance in CPE in the region, through the surveillance of the mcr-1 gene in CPE isolates in Ecuador.

View Article and Find Full Text PDF

Background: Staphylococcus aureus is one of the most common pathogens that colonizes human skin/mucous membranes, where it causes local infection that can progress to invasive infection, resulting in high morbidity and mortality worldwide. This study aimed to investigate the antibiotic susceptibility and molecular characteristics of invasive S. aureus in children and women in Southwest China from 2018 to 2023 to provide novel insights helpful in preventing and treating S.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!