[The Identification of Acinetobacter baumannii Blood Isolates by MALDI-TOF MS, ARDRA and blaOXA-51-like Gene-Specific Real-Time PCR].

In this study, we aimed to evaluate the diagnosis performance of MALDI-TOF MS system to identify blood isolates of A.baumannii. A total of 180 nonduplicate carbapenem resistant Acb complex (strain numbers; TR1-TR60) and A.baumannii (TR61-TR180) blood isolates were collected from the intensive care units of the three university hospitals in Turkey from January 2016 to December 2016. All isolates were evaluated by using blaOXA-51-like gene specific real time (Rt-PCR) analysis, ARDRA (restriction enzymes-AluI, CfoI, MboI, MspI, RsaI) method and MALDI-TOF MS (VITEK® MS, bioMérieux, France) system. All the strains except TR10, TR31, TR35 and TR52 were identified as A.baumannii by ARDRA method. Out of 177 of all the isolates, presence of blaOXA-51-like gene was found except for TR10, TR31 and TR52 isolates. However, TR31 without the presence of blaOXA-51-like gene was identified as A.pittii using the ARDRA. Totally 176 isolates which were identified as A.baumannii by both of the methods, ARDRA and Rt-PCR- blaOXA-51-like, were accepted as a reference for the evaluation of the diagnosis performance capacity of the MALDI-TOF MS. Overall, for all 176 isolates tested, the sensitivity obtained with the MALDI-TOF MS were 99.4% with 75% specificity. The accuracy value of the method was determined as 98.9% for the identification of A.baumannii to the species level. MALDI-TOF MS is increasingly used in diagnostic microbiology for the routine identification of bacteria to the genus, species...
Source: Mikrobiyoloji Bulteni - Category: Microbiology Tags: Mikrobiyol Bul Source Type: research