Detecção de cepas patogênicas pela PCR multiplex e avaliação da sensibilidade a antimicrobianos de Escherichia coli isoladas de leitões diarréicos Detection of pathogenic strains by multiplex PCR and antimicrobial sensitivity of Escherichia coli isolated from piglets

Avaliou-se a freqüência dos genes de fímbrias (K88, K99, 987P, F18 e F41) e toxinas (LT, Stb, StaP e Stx2e) de cepas de E. coli isoladas de leitões com diarréia usando a técnica de PCR multiplex com primers específicos para esses genes, e estudou-se o padrão de sensibilidade das cepas patogênicas pelo método de difusão em disco ao florfenicol, ceftiofur sódico, colistina, fosfomicina, neomicina, norfloxacina, sulfa + trimetoprim, doxiciclina, tetraciclina e lincomicina. Foram utilizadas 144 amostras de E.coli isoladas de leitões com diarréia, provenientes de granjas localizadas no estado de Minas Gerais. Dessas, 42 (29,2%) foram positivas para pelo menos um dos fatores de virulência testados. Dentre essas 42 amostras, 23 (54,8%) apresentaram genes de fímbria e toxina, sete (16,6%) apresentaram somente genes de toxinas e 12 (28,6%) amostras somente genes de fímbria. O resultado do teste de sensibilidade aos antimicrobianos demonstrou que o florfenicol (89,5 %) e o ceftiofur sódico (84,2%) foram as drogas de melhor eficácia in vitro sobre cepas de E. coli com fatores de virulência.<br>The frequency of virulence determinants genes for fimbrial adhesions (K88, K99, 987P, F18 and F41) and toxins (LT, Stb, StaP and Stx2e) in E. coli strains isolated from diarrheic piglets using the multiplex polymerase chain reaction assay with specific primers for these genes was studied. The antimicrobial sensitivity pattern of pathogenic isolates for florfenicol, sodium ceftiofur, colistin, fosfomycin, neomycin, norfloxacin, sulfa + trimetoprim, doxycycline, tetracycline and lincomycin was also tested using the disk diffusion method. E. coli were isolated from 144 diarrheic piglets from farms in the state of Minas Gerais. Forty-two out of 144 studied samples (29.2%) were positive for at least one tested virulence factor. Out of these 42, 23 samples (54.8%) contained fimbria and toxin genes, seven (16.6%) samples had genes for toxins only and 12 (28.6%) samples just fimbria genes. Disk diffusion in vitro antimicrobial sensitivity test demonstrated the best results for florfenicol (89.5%) and sodium ceftiofur (84.2%) against virulent E. coli strains

Detecção da resistência a antibióticos de bactérias isoladas de casos clínicos ocorridos em animais de companhia Detection of antibiotic resistance in clinical bacterial strains from pets

<abstract language="eng">The identification of different bacterial strains and the occurrence of antibiotic resistance were investigated in several infection processes of pets as skin abscess with purulent discharge, bronco alveolar fluid, earwax, urine, mammary, and eye fluid. Streptococcus spp. and Staphylococcus spp. were the most detected in the different samples. A high frequency of antimicrobial resistance has been observed and this could reflect the wide use of antimicrobials in pets, making the effectiveness of antibiotic treatment to become more complicated

Resistência a antimicrobianos de Escherichia coli isolada de dejetos suínos em esterqueiras Antibiotic-resistance of Escherichia coli isolates from stored pig slurry

<abstract language="eng">The antimicrobial resistance of 96 Escherichia coli strains isolated from a stabilization pond system on a pig-breeding farm was evaluated. Strains were tested for their resistance against 14 antimicrobial using the agar diffusion method. E. coli strains showed resistance to tetracycline (82.3%), nalidixic acid (64%), ampicilin (41%), sulfamethoxazole/trimethoprin (36%), sulfonamide (34%), cloranphenicol (274%), ciprofloxacin (19%), cefaclor (16%), streptomicyn (7.3%), neomicyn (1%), amoxacilin/ clavulanic acid (1%), and amikacin (1%). No resistance was observed to gentamicin and tobramycin, and 37.5% of E. coli strains were resistant to four or more antimicrobials. The multiresistance pattern was found in strains isolated during all sampled period. Strains showed a high variability in the antimicrobial resistance pattern