Description of Methicillin-resistant Staphylococcus pseudintermedius from canine pyoderma in Minas Gerais state, Brazil

E Bourguignon,L.G Conceição,M.A.S Moreira,G.N Viçosa,C.M.M Corsini,L.A Nero

doi:10.1590/1678-4162-8150

Abstract

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is of worldwide concern in veterinary medicine. The identification of resistant strains is necessary for proper treatment and the prevention of its propagation among animals. This study aimed to identify S. pseudintermedius isolated from canine pyoderma and evaluate their resistance profiles. Lesions from 25 dogs with pyoderma were sampled. Bacterial isolates were subjected to phenotypic and genotypic analysis for identification of the causative agent. S. pseudintermedius isolates were subjected to SmaI macrorestriction analysis and PFGE for genetic grouping, and PCR to identify the presence of the mecA gene. Their resistance profiles against 12 antimicrobials were also assessed. According to the microbiological analysis, 70 of the 75 isolates obtained were S. pseudintermedius. The isolates presented PFGE patterns, with similarity varying between 84.6 and 100%, and were grouped into 19 clusters. Despite a high frequency of mecA-positive isolates (66 out 70), only 12 presented resistances to oxacillin. Multi-resistance was identified in 29 isolates. The high frequency of MRSP isolated in this study highlights the relevance of identifying resistant strains to lead proper clinical treatment.

Highlights

Staphylococcus pseudintermedius is considered the most frequently isolated agent from canine pyoderma (Devriese et al, 2009), being the most common reason for antimicrobial use in dogs
Considering the microbiological analysis, 70 of the 75 isolates obtained from 25 animals were identified as S. pseudintermedius and the other five isolates were classified as Staphylococcus sp
Another study that evaluated isolates from lesions of atopic dermatitis in dogs found that isolates from the same animal were often related or even identical based on PFGE (Fazakerley et al, 2010)

Summary

Introduction

Staphylococcus pseudintermedius is considered the most frequently isolated agent from canine pyoderma (Devriese et al, 2009), being the most common reason for antimicrobial use in dogs. The most reliable test to identify MRS is a PCR protocol targeting the mecA gene, which encodes the supplemental penicillin-binding protein, PBP2a (Schissler et al, 2009). This protein is expressed either homogeneously, which is detected with standard testing methods, or heterogeneously, which is more difficult to detect with those methods, since only a fraction of the population expresses the resistance phenotype (Bemis et al, 2006). This study aimed to characterize S. pseudintermedius isolates from canine pyoderma by phenotypic and genotypic methods, and evaluate their resistance profiles to antimicrobials and the presence of the mecA gene

Objectives

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Results

Conclusion