A meta-analysis study on colistin resistance in Acinetobacter baumannii species in Turkey

Aim: Acinetobacter baumannii is a nosocomial infectious agent that may be resistant to several antimicrobial drugs, including colistin. Colistin is a crucial antimicrobial agent in resistant A. baumannii infections. Colistin resistance varies between countries and regions worldwide. This study aimed to evaluate the studies on colistin resistance of A. baumannii strains in different regions of Turkey, show the increasing colistin resistance in years, and discuss the solution suggestions. Methods: The online electronic database was searched for studies evaluating the antibacterial efficacy of colistin combined with other antibiotics or alone in clinical samples of patients with A. baumannii infection. Results: In our study, colistin susceptibility was found to be between 81.8%-100% in Turkey. The lowest susceptibility to colistin for A. baumannii strains was reported in the Aegean Region (81.8-100%), followed by Black Sea (82.4-100%), Southeast Anatolia (94-96%), Central Anatolia (95.8-100), Marmara (96.8-100%), Mediterranean (98-100%), respectively, and the highest susceptibility was found in Eastern Anatolia Region (98.6-100%). According to the studies, a partial decrease in colistin sensitivity was found in some regions over the years and more decrease in others, but this decrease was not statistically significant (p> 0.05). The cities with the lowest colistin susceptibility were reported as İzmir 81.8%, Samsun 82.4%, Diyarbakır 94%, Düzce 94.1% and Ankara 95.8%. Conclusion: Colistin is still the most effective antimicrobial drug in A. baumannii infections. Our study concluded that there were some differences between regions and even within the same region in colistin susceptibility of A. baumannii in Turkey, and resistance development has increased over the years.