Comparison of two different methods for tigecycline susceptibility testing in acinetobacter baumannii.

COMPARISON OF TWO DIFFERENT METHODS FOR TIGECYCLINE SUSCEPTIBILITY TESTING IN ACINETOBACTER BAUMANNII. Acta Clin Croat. 2018 Dec;57(4):618-623 Authors: Bedenić B, Cavrić G, Vranić-Ladavac M, Barišić N, Karčić N, Tot T, Presečki-Stanko A, Lukić-Grlić A, Frančula-Zaninović S, Sreter KB Abstract - Tigecycline susceptibility testing (TST) presents a tremendous challenge for clinical microbiologists. Previous studies have shown that the Epsilometer test (E-test) and Vitek 2 automated system significantly overestimate the minimum inhibitory concentrations for tigecycline resistance compared to the broth microdilution method (BMM). This leads to very major errors or false susceptibility (i.e. the isolate is called susceptible when it is actually resistant). The aim of this study was to compare E-test against BMM for TST in carbapenem-resistant and carbapenem-susceptible Acinetobacter (A.) baumannii and to analyze changes in tigecycline susceptibility between two time periods (2009-2012 and 2013-2014), with BMM as the gold standard. Using the EUCAST criteria, the rate of resistance to tigecycline for the OXA-23 MBL-positive, OXA-23 MBL-negative and carbapenemase-negative strains for BMM was 54.5% (6/11), 29.4% (5/17) and 2.7% (1/37), respectively; the OXA-24/40 and OXA-58 producing organisms did not exhibit any resistance. With E-test, all OXA-23 MBL-positive organisms (11/11), 23.5% (4/17) of OXA-23 MBL-negative, and 4.1% of OXA...
Source: Acta Clinica Croatica - Category: General Medicine Tags: Acta Clin Croat Source Type: research