Are all meticillin‐resistant Staphylococcus aureus (MRSA) equal in all hosts? Epidemiological and genetic comparison between animal and human MRSA

Meticillin-resistant Staphylococcus aureus (MRSA) continues to pose a major threat to human health. In animals, MRSA has become established as a veterinary pathogen in pets and horses; in livestock, it presents a concern for public health as a reservoir that can infect humans and as a source of transferrable resistance genes. Genetic analyses have revealed that the epidemiology of MRSA is different in different animal hosts. While human hospital-associated MRSA lineages are most commonly involved in pet infection and carriage, horse-specific MRSA most often represent 'traditional' equine S. aureus lineages. A recent development in the epidemiology of animal MRSA is the emergence of pig-adapted strains, such as CC398 and CC9, which appear to have arisen independently in the pig population. Recent insight into the genome structure and the evolution of S. aureus has helped to explain key aspects of these three distinct epidemiological scenarios. This nonsystematic literature review summarizes the structure and variations of the S. aureus genome and gives an overview of the current distribution of MRSA lineages in various animal species. It also discusses present knowledge about the emergence and evolution of MRSA in animals, adaptation to different host species and response to selective pressure from animal-specific environments. An improved understanding of the genetics and selective pressure that underpin the adaptive behaviour of S. aureus may be used in the future to predict new developments in staphylococcal diseases and to investigate novel control strategies required at a time of increasing resistance to antimicrobial agents.     

Infection by Eucoleus aerophilus in dogs and cats: Is another extra-intestinal parasitic nematode of pets emerging in Italy?

The occurrence of the infection by the lungworm Eucoleus aerophilus (syn. Capillaria aerophila) in dogs and cats from Italy has been evaluated with conventional diagnostic procedures. Individual faecal samples from 569 dogs and 200 cats were undertaken to faecal flotation with sugar and zinc sulphate solution. Sixteen dogs (2.8%) and 11 cats (5.5%) scored positive for eggs of E. aerophilus when samples were processed with either of the two flotation solutions. Overall 14 of 16 dogs and eight of 11 cats infected by E. aerophilus showed respiratory symptoms and the most common were general respiratory distress, dry cough, wheezing and sneezing. These results indicate that E. aerophilus is not uncommon and that canine and feline capillariosis is of clinical importance. Given the impact that E. aerophilus infections may have upon animal health and its zoonotic potential, it is strongly advisable to routinely include this disease in the differential diagnosis of (cardio)-respiratory diseases of dogs and cats.     

Anti-Müllerian hormone in dogs and cats reproduction

The anti-Müllerian hormone (AMH) is a glycoprotein secreted by Sertoli cells in males and granulosa cells in females. It has first been determined in blood serum of dogs and cats by Place et al. in 2011 with the use of a human-based ELISA test. Meanwhile, different immunoassays have been validated for AMH determination in animals and a variety of studies have demonstrated the clinical significance of AMH. This review summarizes the current knowledge about AMH in dogs and cats and describes future opportunities for its diagnostic use.     

Abnormal platelet activity in dogs and cats – impact and measurement

Abnormal platelet activity can either lead to bleeding tendencies or inappropriate thrombus formation and can occur secondarily to a wide variety of disease processes, with a range of clinical consequences and severity. This article will discuss the pathophysiology of platelet function abnormalities and consider a logical diagnostic approach applicable to veterinary practice. Recent advances in platelet function testing will then be discussed, with regards to detection of platelet dysfunction and tailoring of pharmacological manipulation. Although many of these tests are still confined to research or academic institutions, techniques for indirectly assessing platelet function are starting to become more widely available. Although we still require further research to develop guidelines for the use of these tests in clinical decision-making, the recent advances in this field are an exciting step forward in being able to detect and manage platelet dysfunction in both primary care and referral practice.     

Companion Animals Symposium: Obesity in dogs and cats: What is wrong with being fat?

Few diseases in modern pets are diet induced. One possible exception to this is obesity, which is ultimately caused by consuming more calories than needed by the dog or cat. Although fat is the most concentrated and efficiently stored source of calories, and protein least so, an excess of calories from any source will contribute to adiposity. Obesity is an excess of body fat sufficient to result in impairment of health or body function. In people, this is generally recognized as 20 to 25% above ideal BW. This degree of excess is important in dogs as well. A lifelong study in dogs showed that even moderately overweight dogs were at greater risk for earlier morbidity; these dogs required medication for chronic health problems sooner than their lean-fed siblings. The average difference in BW between groups was approximately 25%. Obese cats also face increased health risks, including an increased risk of arthritis, diabetes mellitus, hepatic lipidosis, and early mortality. The risk for development of diabetes increases about 2-fold in overweight cats and about 4-fold [corrected] in obese cats. Altered adipokine secretion appears to be an important mechanism for the link between excess BW and many diseases. Once considered to be physiologically inert, adipose tissue is an active producer of hormones, such as leptin and resistin, and cytokines, including many inflammatory cytokines such as tumor necrosis factor-α, IL-1β and IL-6, and C-reactive protein. The persistent, low-grade inflammation secondary to obesity is thought to play a causal role in chronic diseases such as osteoarthritis, cardiovascular disease, diabetes mellitus, and others. For example, tumor necrosis factor-α alters insulin sensitivity by blocking activation of insulin receptors. In addition, obesity is associated with increased oxidative stress, which also may contribute to obesity-related diseases. Management of obesity involves nutritional modification as well as behavioral modification. Increased protein intake combined with reduced calorie intake facilitates loss of body fat while minimizing loss of lean body mass. Limiting treats to 10% of calorie intake and increasing exercise both aid in successful BW management.     

Methicillin-resistant Staphylococcus aureus (MRSA) in veterinary medicine: a "new emerging pathogen"?

The problem of nosocomial infections is of increasing importance in veterinary medicine. As an example, this review summarizes current knowledge regarding methicillin-resistant Staphylococcus aureus (MRSA) as a typical example, as these pathogens are the most important agents of nosocomial infections in human medicine worldwide and are being increasingly reported in veterinary medicine. MRSA are classified by their ability to be resistant against oxacillin/methicillin, this feature being confered by mecA, a gene which was acquired by horizontal gene transfer of the staphylococcal gene cassette (SCCmec). It is this genetic information that enables MRSA to be resistant against all penicillins, cehalosporins and carbapenems. In addition, MRSA are often resistant against a variety of other antiinfectives, i.e. aminoglycosides, macrolides, lincosamide, streptomycins, tetracyclin, chloramphenicol, but also against fluorquinolones and rifampicin. Presumably, these highly adapted strains are particularly able to acquire resistance genes located on plasmids or transposons.They are also able to develop point mutations, further leading to resistant phenotypes. If these pathogens are leading to infectious diseases, veterinarians may be confronted with a worst-case scenario, being left without any antiinfective therapeutic. As Staphylococcus aureus is highly tenacid, professional hygiene management is of utmost importance. The increasing number of published sporadic MRSA infections, MRSA-infectious diseases as well as MRSA outbreaks in veterinary medicine justifies their recognition as a "New Emerging Pathogen". So far, horses and dogs are mostly affected by MRSA. Although transmission between humans and animals has been reported occasionally, the sources, routes of transmission or the epidemiological relevance of MRSA infections in animals are far from being understood. Therefore, epidemiological investigations utilizing molecular typing tools are mandatory. Typing tools like multilocus-sequence-typing (MLST), pulsefield-gelelectrophoresis (PFGE), sequence analysis of the gene encoding protein A (spa-typing) as well as SCCmec-typing are all at hand.     

Is there a link between bacteriuria and a reversible encephalopathy in dogs and cats?

Bacteriuria has been associated with abnormal neurological status in humans, especially geriatric patients. In this report, we review 11 cases (seven dogs and four cats) that suggest an association between bacteriuria and abnormal neurological status in veterinary medicine. These cases showed diffuse forebrain signs with or without brainstem signs, but primary brain disease was excluded by MRI and cerebrospinal fluid analysis. Bacteriological culture of urine was positive in each animal and neurological deficits improved or resolved with initiation of antibiosis ± fluid therapy and levetiracetam. While further studies are needed to definitively confirm or refute the link between bacteriuria and a reversible encephalopathy, urine bacteriological culture should be considered in veterinary patients presented with acute onset forebrain neuro-anatomical localisation, even in the absence of clinical signs of lower urinary tract inflammation.     

Molecular epidemiological and phylogenetic analyses of canine parvovirus in domestic dogs and cats in Beijing, 2010–2013

Fifty-five samples (15.62%) collected from dogs and cats were identified as canine parvovirus (CPV) infection in Beijing during 2010–2013. The nucleotide identities and aa similarities were 98.2–100% and 97.7–100%, respectively, when compared with the reference isolates. Also, several synonymous and non-synonymous mutations were also recorded for the first time. New CPV-2a was dominant, accounting for 90.90% of the samples. Two of the 16 samples collected from cats were identified as new CPV-2a (12.5%), showing nucleotide identities of 100% with those from dogs. Twelve samples (15.78%) collected from completely immunized dogs were found to be new CPV-2a, which means CPV-2 vaccines may not provide sufficient protection for the epidemic strains.     

Selection of antibiotics for meticillin‐resistant Staphylococcus pseudintermedius: time to revisit some old drugs?

The aim of this review is to consider systemic therapy options for meticillin-resistant Staphylococcus pseudintermedius (MRSP). Infections caused by MRSP in small animals--particularly dogs--have been frustrating veterinarians in recent years. After a susceptibility test is performed, veterinarians are left to select from drugs that have not been frequently encountered on a susceptibility report. Some of these are old drugs that have not been used regularly by veterinary dermatologists. As MRSP is, by definition, resistant to all β-lactam antibiotics, including cephalosporins, penicillins and amoxicillin-clavulanate combinations, the β-lactam drugs are not an option for systemic treatment. As most MRSPs are multidrug resistant, familiar drugs, such as trimethoprim-sulfonamides, fluoroquinolones, macrolides and lincosamides (clindamycin), are also not usually an option for treatment. Therefore, veterinarians are left with drugs such as rifampicin, chloramphenicol, tetracyclines, aminoglycosides and vancomycin to choose from on the basis of an in vitro susceptibility test. Some of these drugs were originally approved over 50 years ago and may not be familiar to some veterinarians. Each of these drugs possesses unique properties and has particular advantages and disadvantages. Veterinarians should be particularly aware of the adverse effects, limitations and precautions when using these drugs. New drugs also have been developed for meticillin-resistant Staphylococcus aureus in humans. These include linezolid, ceftaroline, daptomycin and tigecycline. Although these drugs are very infrequently--if ever--considered for veterinary use, the properties of these drugs should also be known to veterinary dermatologists.     

Larval cyathostominosis in horses in Ontario: an emerging disease?

From 1991 to 2003, 24 cases of larval cyathostominosis were diagnosed at postmortem in equids, 15 (63%) from 2001 to 2003. Cases occurred from September to May, the majority from October to December. Median age was 12 mo. Diarrhea, colic, and weight loss were common clinical signs. Hypoalbuminemia and microcytosis were consistent findings.     

Tick paralysis in dogs and cats in Australia: treatment and prevention deliverables from 100 years of research

This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all – a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.     

Intestinal parasites of dogs and cats in Australia: The veterinarian’s perspective and pet owner awareness

During a recent national study of intestinal parasites in dogs and cats in Australia, questionnaires were submitted to veterinarians and pet owners to evaluate from a veterinary and public health standpoint the veterinarians’ perception, awareness and knowledge of gastrointestinal parasites in their locality. The study included sourcing information with regard to commonly recommended deworming protocols. The awareness of pet owners regarding parasitic zoonoses and the degree of education provided to them by veterinarians was also determined.Very few veterinarians routinely discussed the zoonotic potential of pet parasites with clients but most recommended regular prophylactic administration of anthelmintics throughout a pet’s life. Some pet owners were unaware of the existence of zoonoses. It is possible that an overreliance on anthelmintics may have led to a certain complacency about the need to educate pet owners about the risks of zoonoses. Veterinarians are important educators in the community and it is important to evaluate their performance if improvements are to be made.     

Preanaesthetic blood tests in cats and dogs older than 8 years: anaesthetists’ prediction and peri-anaesthetic changes

ObjectiveTo evaluate the anaesthetist’s ability to predict abnormalities in preanaesthetic blood test results obtained from cats and dogs older than 8 years and to describe the impact of these preanaesthetic blood test results on the American Society Anesthesiologists (ASA) physical status classification, anaesthetic protocol and procedures.Study designObservational, prospective, clinical multi-centre study.AnimalsA total of 333 cats and dogs.MethodsAfter a clinical examination and review of the animal´s clinical history the anaesthetist completed the first part of a set of questions including ASA status and anticipated abnormalities in blood tests. After this, blood results were presented, and the anaesthetist completed the second part of the set of questions, including changes in ASA status or anaesthetic protocol, and procedure delay or cancellation. Preanaesthetic blood tests included: haematocrit, total proteins, electrolytes, glucose, lactate, urea and creatinine. Examiners were classified as senior clinicians, clinicians, anaesthesia residents or nurses, and interns. For statistical analysis, the chi-square test was used. A p value < 0.05 was considered significant.ResultsThe ASA status increased in three dogs and one cat (1.2%); in two of them abnormalities were not expected by the examiner. The anaesthetic protocol changed in seven animals (2.1%); the most common change related to fluid therapy. Anaesthesia was delayed in two dogs (0.6%) to administer intravenous fluid therapy. No cases were cancelled. Abnormalities were more commonly found [37 out of 58 assessments (approximately 64%)] when the anaesthetist predicted them compared to when they were unexpected [49 of 275 assessments (approximately 18%); p < 0.001].Conclusions and clinical relevanceRoutine non-targeted blood tests in cats and dogs older than 8 years led to few changes in the anaesthetic management, and anaesthetists correctly predicted blood test results in most cases.