Among multiresistant Gram-positive microorganisms, stands out methicillin-resistant Staphylococcus (MRS), an opportunistic pathogen associated with hospital acquired and community infections reported in medicine and large increase in reports of veterinary medicine. In veterinary medicine, numerous reports regarding several species of animals have been described. MRS is intrinsically resistant to all β-lactam drugs. In veterinary medicine, numerous reports regarding several species of animals have been described, but Staphylococcus aureus with intermediate resistance and resistant to vancomycin (VISA/ VRSA) has not yet been reported in veterinary medicine, still need further study. Staphylococcus spp. are also related to antimicrobial resistance of macrolides, lincosamides, and streptogramin B (MLSB) group, that has the same mechanism of action, although the drugs belong to different classes. In veterinary medicine, clindamycin (lincosamide class) is widely used for skin infections, wounds, bone infections, pneumonia, infections of the oral cavity, and infections caused by anaerobic bacteria, besides being used for treatments of MRS infections. Enterococcus is another resistant Gram-positive microorganism, from which vancomycin-resistant enterococci (VREs) are the most important strains. There are several reports of VREs in veterinary medicine due the use of a similar antimicrobial (avoparcin) in livestock; therefore this group of microorganisms has now acquired great prominence since vancomycin is considered as the last resort for the treatment of MRS and Enterococcus associated with nosocomial infections in humans. The biggest problem these microorganisms and their resistance mechanisms cause is related to its huge impact on public health due to the increasing close contact between animals and humans. The objective of this review was to identify the main Gram-positive microorganisms associated with animals, describing their mechanisms of action that lead to antimicrobial resistance, as well as their impact on public health through their zoonotic and anthropozoonotic potential. tanto a infecções hospitalares como infecções comunitárias, tendo inúmeros relatos na medicina e um grande aumento de relatos na medicina veterinária, em diversas espécies de animais. MRS são intrinsicamente resistentes a todas as drogas beta-lactâmicas. Os Staphylococcus aureus com resistência intermediária e os resistentes à vancomicina (VISA/VRSA) ainda não foram reportados em animais, porém são necessários estudos mais aprofundados. Os Staphylococcus spp. também estão relacionados com resistência aos antimicrobianos do grupo dos Macrolídeos, Lincosamidas e Streptogramineas B (MLSb), que apesar de serem de classes diferentes, possuem o mesmo mecanismo de ação. Na medicina veterinária, a clindamicina (antimicrobiano da classe da Lincosamida) é amplamente utilizada para tratamentos de infecções de pele, feridas, infecções ósseas, pneumonia, infecção da cavidade oral e infecções causadas por bactérias anaeróbicas, além de ser util...

Background: Antimicrobial resistance is described as a condition in which a micro-organism is able to survive when exposed to an antimicrobial agent. The resistance rates to antimicrobials in companion animals have risen considerably. Studies of local antimicrobial susceptibility profiles are needed as well as education and warning about the use of tests for the identification and susceptibility of pathogenic bacterial strains. The aim of this study was to identify the main antimicrobial resistance in clinical samples of dogs, and to detect multidrug-resistant strains of importance to public health.Materials, Methods & Results: Bacterial pathogens of 77 dog infections were isolated and their sensitivity profile to antimicrobials was determined. One hundred bacterial isolates were identified. Of these, 61 were Gram-positive (55 Staphylococcus spp., 4 Enterococcus spp. and 2 Streptococcus spp.) and 39 Gram-negative (36 fermenters and 3 non-fermenters). Seventy-nine isolates were considered multiresistant following individual assessment of drugs, and 85 following the evaluation of classes. Only 3 were sensitive to all drugs. Four isolates were resistant to all classes and only sensitive to some antibiotics. Of the 55 samples of Staphylococcus spp., 36 (65.45%) were identified as phenotypically MRS. Two isolates of Enterococcus spp. were resistant to vancomycin (VRE). Also 66.67% (26/39) of the samples were positive for the presumptive test for ESBL. For the MRS-positive isolates detected in this study, chloramphenicol was the antimicrobial that showed superior sensitivity in 74.29% of the cases (27/36); therefore it is considered the most appropriate for treatment of this type of micro-organism. In case of aminoglycosides, when their resistance was checked in MRS isolates, all resistance percentages increased, implying a limited use of this class for such a type of multi-resistant micro-organism. Contrarily, in case of ESBL, a superior sensitivity was observed towards MRS isolates, thus making them a prime treatment choice for the infection caused by these micro-organisms.Discussion: Literature have reported a gradual increase in multidrug resistance towards antimicrobial agents in veterinary medicine over the past decades. In this study, 64% of multiresistant strains were considered of significant importance, notably MRS (36), VRE (2) and ESBL (26). The early identification of pathogens in animals has become an important step in order to minimize the transmission of antibacterial resistance. The increase in the number of multidrug-resistant bacteria in animals and humans demonstrates the need to develop and implement measures in order to monitor and control the spread of this resistance. It is possible that the increased drug resistance is linked to the constant exposure to these drugs and the subsequent selective pressure, causing the transfer of resistant genes between strains. Carbapenems and glycopeptides should be used with caution in veterinary medicine in order to prevent such processes of selection that develop resistance in micro-organisms to these two classes, which can result in cross-resistance between animals and humans and create obstacles in the treatment of patients, especially for the two drugs mentioned, since they are important for the treatment of nosocomial infections in humans. The resistance percentage towards fluoroquinolones was identified to be higher in Gram-positive isolates, particularly in MRS, which showed 75% resistance against this class (according to the CLSI, resistance to one fluoroquinolone antimicrobial agent provides resistance to other antimicrobials of this class). For ESBL isolates, the resistance was shown to be 50%. The resistance towards the fluoroquinolones and aminoglycosides class can be associated with the expression of the genes that produce ESBL.

No abstract

The objective of this study was to identify the main microorganisms associated with ophthalmic infections and determine the resistance profile of these isolates against antimicrobial drugs. 26 bacterial isolates from 18 canine ophthalmic infections were submited to the phenotypic resistance profile for 36 drugs of 12 classes of antimicrobials, research of multidrug-resistant strains with importance in public health and detection of Staphylococcus mecA gene by PCR. The bacterial isolates were identified as Staphylococcus spp. (n = 18), Enterococcus spp. (n = 1), enterobacteria (n = 6) and Pseudomonas spp. (n = 1). The percentage of resistance and intermediate resistance were 42.48% (n = 325). Considering separate antimicrobials drugs, 18 isolates were characterized by multidrug resistant, while by the assesment of resistance to class, 20 isolates were multiresistant. In the phenotypic detection, 61.11% (11/18) of Staphylococcus spp. were predicted by Methicillin-Resistant Staphyloccus (MRS), whereas the genotypic detection, 38.89% (7/18) were carriers of the mecA gene. Two enterobacterias were considered producers of expectro Extended of Betalactamase (ESBL). EUCAST was more reliable for detecting MRS strains than the CLSI. The present study detected multiresistant isolates of great importance and are involved in cases of public health, such as MRS, MRSMLSb, ESBL, very important to be readily identified and controled so as to prevent the spread of this type of resistance.

WOSIACKI 5As bactérias Gram-positivas são os principais microrganismos encontrados na microbiota conjuntival dos animais (TOLAR et al., 2006), porém os microrganismos Gram-negativos também podem ser isolados em animais saudáveis, mas quando em grande número pode indicar um estado anormal de saúde ocular (SPINELLI et al. 2010 Streptococcus foi resistente apenas à neomicina, tetraciclina e levofloxacina, de 29 antibióticos testados. Já as amostras de Staphylococcus spp., seis apresentaram resistência a oxacilina, o que indica uma resistência intrínseca aos antimicrobianos beta-lactâmicos. Quanto à penicilina e a ampicilina, 92,85% das amostras mostraram-se resistentes e 78,6% apresentaram resistência a amoxacilina, tetraciclina, sulfazotrim e clindamicina, porém não houve resistência aos carbapenêmicos e houve baixa resistência as cefalosporinas (cefalexina, cefalotina e ceftriaxona), amicacina, levofloxacina, tobramicina e cloranfenicol (28,5%, 14,3%, 28,5%, 35,7% e 35,7% respectivamente). Esses resultados mostram a importância do controle aos agentes antimicrobianos na medicina veterinária, levando em conta os altos índices de resistência.

No abstract

A cicatrização de feridas quando manejadas corretamente evolui rapidamente, porém fatores como idade, imunossupressão e doenças concomitantes podem influenciar na recuperação das lesões. O uso de antimicrobianos é importante para controle da microbiota da pele e previne infecções secundárias e septicemias. Graças à complexidade dos mecanismos de resistência, a escolha dos antimicrobianos tornouse uma difícil missão, aumentando a morbidade e mortalidade dos pacientes tratados indevidamente (ARIAS et al., 2008)

No abstract