DETECTION OF RESISTANCE MECHANISMS OF NEGATIVE GRAM BACTERIA ISOLATED IN DIFFERENT HOSPITAL ENVIRONMENTS IN VETERINARY MEDICINE

With the increase of reports of bacterial resistance worldwide, the adoption of additional tests in clinical laboratory diagnosis is of fundamental importance in the detection of different mechanisms of resistance. The objective of this work was to detect different mechanisms of resistance presented by Gram negative bacteria isolated in the Veterinary Hospital of the Universidade Estadual de Maringá – Campus Regional de Umuarama. Samples were collected in march 2018 by swab from different surfaces of twenty-two hospital environments: 1) Secretariat; 2) Reception; 3) Ambulatory 1; 4) Ambulatory 2; 5) Clinical Surgical Hospitalization; 6) Medical Clinic Hospitalization; 7) Sterilization Room; 8) Cup; 9) Surgical Center; 10) Room for Pre-Anesthetic Medication 1; 11) Pharmacy; 12) Ultrasound and Radiography Room; 13) Residents Room; 14) Large Animals Warehouse; 15) restrooms; 16) Laboratory of Parasitology; 17) Laboratory of Clinical Pathology; 18) Ambulatory for vaccination; 19) Surgical Center of Large Animals; 20) Operative Technique; 21) Surgical Center 2; and 22) Room for Pre-Anesthetic Medication 2. Swabs were initially inoculated in TSB broth with ceftriaxone (2 μg/mL) followed by sowing on MacConkey and Nutrient agar. The samples were submitted to conventional biochemical identification tests. The antibiogram for amoxicillin, gentamicin, chlorofenicol, norfloxacin, sulfazotrim and tetracycline was performed; the test for the detection of bacteria of extended-spectrum beta-lactamase (ESBL); the disc combination test for the detection of carbapenemase production (CR); the Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (CBM) for Ceftriaxone (CTX) and Meropenem (MPM). Gram-negative fermentative bacteria were isolated in 10 of the 22 environments, being characterized 14 strains, 9 identified as Hafnia alvei. Four phenotypic resistance profiles were observed among strains isolated from the following environments: profile A: cup and Large Animals Warehouse; B: cup and Ultrasound and Radiography Room; C: Medical Clinic Hospitalization, restrooms and Laboratory of Parasitology; and D: resident's room, restrooms, Laboratory of Clinical Pathology and surgical center 2. ESBL production was verified in 64.3% (9/14) and CR production in only 1 (one) bacterial isolate. In MIC, performed in microdilution with concentrations of 0.5 to 256 μg/mL for both antibiotics, 100% had resistance to ceftriaxone (≥1 ug/mL) and 21,4% to meropenem (≥4 ug/mL). In the evaluation of CBM, the results for CTX were similar to the MIC, already for MPM, resistance of 42,8% of the isolated strains was observed.