Antibiotic Resistance of <em>Acinetobacter </em>Isolated in a Spanish Veterinary Teaching Hospital

Acinetobacter is one of the most relevant pathogenic and nosocomial bacterial genus in human medicine. However, in veterinary medicine, and especially in Spain, there are very few studies about the impact and frequency of infections due to this genus. The main objective of this study was to characterise Acinetobacter isolates analysed at the Complutense Veterinary Teaching Hospital of the Complutense University of Madrid, with special emphasis on detecting antimicrobial resistance. A total of 23 isolates obtained from different animal species and samples over a 27-year period, were included in the study. Identification was made by using MALDITOF, VITEK-2, whole-genome sequencing and a chromogenic medium. Antimicrobial susceptibility was interpreted according to CLSI guidelines using the Kirby-Bauer disk diffusion and broth microdilution method. The proportion of clinical isolates identified as Acinetobacter spp. at the HCV-UCM was 0.3%. The frequency of AMR was low, though 30.8% of the isolates were classified as multidrug-resistant. Two isolates with the highest MIC for temocillin carried the tet(X) gene, and two isolates had mutations in both gyrA and parC QRDR regions. The results of this study suggest that, in Spain, antimicrobial resistance in Acinetobacter isolates of veterinary origin might not be yet widespread.