A carregar...
Publicação
Produção de biofilme em staphylococci isolados da pele de canídeos
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 1.71 MB | Adobe PDF |
Autores
Orientador(es)
Resumo(s)
O biofilme é um factor de virulência que confere vantagem evolutiva aos microrganismos
que o possuem, uma vez que favorece a sua cooperação metabólica e permuta genética,
além de lhes conferir protecção contra o sistema imunitário do hospedeiro e contra agentes
antimicrobianos.
Este estudo teve como principal objectivo avaliar a capacidade de produção de biofilme de
staphylococci isolados da pele de cão e relacioná-la com a sua antibiorresistência. Foram
investigados 21 staphylococci colhidos no Hospital Veterinário do Restelo, 11 isolados de
pele saudável (grupo 1) e 10 isolados de casos clínicos de dermatite (grupo 2).
As espécies maioritariamente identificadas foram Staphylococcus epidermidis (25%),
Staphylococcus aureus (17%) e Staphylococcus chromogenes (17%) no grupo 1 e
Staphylococcus capitis (50%), Staphylococcus pseudintermedius (30%) e Staphylococcos
chromogenes (20%) no grupo 2.
A maioria das bactérias isoladas (90%) foi resistente a pelo menos 2 grupos de agentes
antimicrobianos, sendo os compostos activos menos eficazes a penicilina G, a ampicilina e o
ácido nalidíxico, com resistências entre 80% e 100%.
Verificou-se ainda que cerca de 40% dos staphylococci investigados são multirresistentes,
não sendo susceptíveis a pelo menos 5 dos 7 grupos antimicrobianos investigados.
Quanto à produção de biofilme, 38,1 % dos isolados foi considerado positivo a este factor de
virulência, tendo os staphylococci isolados de pele saudável expressado biofilme mais
frequentemente (55%), do que os isolados de dermatites caninas (20%).
Foi ainda verificada uma correlação positiva entre a produção de biofilme e a
antibiorresistência de vários grupos antimicrobianos, nomeadamente penicilinas,
aminoglicosídeos, quinolonas e sulfamidas, o que sugere que a aquisição de genes de
resistência é maior no contexto de um biofilme do que nas células bacterianas equivalentes
de vida livre.
ABSTRACT - Biofilm is a virulence factor which grants evolutionary advantage to microorganisms that possess it, once it favors their metabolic cooperation and genetic shift, besides granting protection against the host's immune system and antibiotics. This study's purpose was to evaluate production capacity for biofilm by bacterial staphylococci isolates from canine skin, and relate it to antimicrobial resistance. Of the 21 isolates obtained from dogs at Hospital Veterinário do Restelo, 11 of wich from healthy skin and the remaining 10 from dermatitis cases, the most frequently identified species were Staphylococcus epidermidis (25%), Staphylococcus aureus (17%) and Staphylococcus chromogenes (17%) in group 1 and Staphylococcus capitis (50%), Staphylococcus pseudintermedius (30%) and Staphylococcus chromogenes (20%) in group 2. Most of isolated bacteria (90%) were resistant to, at least 2 classes of antimicrobials, and the least efficient antibiotics were Penicillin G, Ampicilin, and Nalidixic Acid, with resistances rates between 80% and 100%. A high level of multiresistance was observed, with 40% of all staphylococci being resistant to at least 5 of the 7 investigated antimicrobial groups. Regarding biofilm expression, 38.1% of the isolates were considered to be positive to this virulence factor, with staphylococci isolated from healthy skin having expressed biofilm more frequently (55%) than those isolated from dermatitis cases (20%). A positive correlation was shown between biofilm production and resistance to antimicrobial from several groups, namely penicillins, aminoglycosides, quinolones and sulfamids. This suggests that bacteria growing in biofilm acquire resistance genes more easily that planktonic cells of the same organism.
ABSTRACT - Biofilm is a virulence factor which grants evolutionary advantage to microorganisms that possess it, once it favors their metabolic cooperation and genetic shift, besides granting protection against the host's immune system and antibiotics. This study's purpose was to evaluate production capacity for biofilm by bacterial staphylococci isolates from canine skin, and relate it to antimicrobial resistance. Of the 21 isolates obtained from dogs at Hospital Veterinário do Restelo, 11 of wich from healthy skin and the remaining 10 from dermatitis cases, the most frequently identified species were Staphylococcus epidermidis (25%), Staphylococcus aureus (17%) and Staphylococcus chromogenes (17%) in group 1 and Staphylococcus capitis (50%), Staphylococcus pseudintermedius (30%) and Staphylococcus chromogenes (20%) in group 2. Most of isolated bacteria (90%) were resistant to, at least 2 classes of antimicrobials, and the least efficient antibiotics were Penicillin G, Ampicilin, and Nalidixic Acid, with resistances rates between 80% and 100%. A high level of multiresistance was observed, with 40% of all staphylococci being resistant to at least 5 of the 7 investigated antimicrobial groups. Regarding biofilm expression, 38.1% of the isolates were considered to be positive to this virulence factor, with staphylococci isolated from healthy skin having expressed biofilm more frequently (55%) than those isolated from dermatitis cases (20%). A positive correlation was shown between biofilm production and resistance to antimicrobial from several groups, namely penicillins, aminoglycosides, quinolones and sulfamids. This suggests that bacteria growing in biofilm acquire resistance genes more easily that planktonic cells of the same organism.
Descrição
Dissertação de Mestrado Integrado em Medicina Veterinária
Palavras-chave
Staphylococci biofilme antibiorresistência pele dermatite cão biofilm resistance to antibiotics skin dermatitis dog
Contexto Educativo
Citação
Georgieva, R.N. (2012). Produção de biofilme em staphylococci isolados da pele de canídeos. Dissertação de Mestrado. Universidade Técnica de Lisboa, Faculdade de Medicina Veterinária, Lisboa.
Editora
Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária