Happenings at BluePearl in Arizona
We hope you all had a wonderful holiday season and a happy new year. Our team is pleased to be sending you the first official BluePearl Companion newsletter for the Phoenix area. Companion contains medical articles written by our BluePearl clinicians throughout the United States on subjects we hope you find useful in your daily practice.
We would like to take this opportunity to introduce two new clinicians to our veterinary team in Scottsdale. Sara Ford, DVM, DACVIM, is an experienced internal medicine specialist who is a frequent speaker at national conferences and has published numerous scientific articles and book chapters. She has also served as a consultant for Abbott, Zoetis and Boehringer Ingelheim, and was significantly involved with the development of the AlphaTrack® glucometer. Dr. Ford’s particular interests include immune-mediated diseases, gastrointestinal, liver and pancreatic disorders, and feline medicine and endocrine diseases, particularly diabetes mellitus.
New to our Scottsdale imaging team is Daschelle Roice, DVM, DABVP. In addition to ultrasonography, Dr. Roice will make use of our Toshiba Aquilion 16-slice CT scanner as part of our commitment to offer prompt and sophisticated imaging services to our primary veterinary care partners. Our CT service is available 24 hours a day, seven days a week.
The Importance of Veterinary Oral Hygiene
Susan Yohn, DVM, MS, DABVP (Canine & Feline Practice), DACVIM
BluePearl in Chicago
February is National Pet Dental Health Month, so this is a great time to promote veterinary dentistry with our clients. As veterinary professionals, we are responsible for promoting dental prophylaxis procedures to keep our patients healthy, as well as educating our clients on the importance of preventative oral care for their pets.
Dental disease is commonly diagnosed in dogs and cats. It is estimated that 80% of adult dogs and 70% of adult cats have some form of oral disease. Dental problems, especially when halitosis is present, are among the top reasons for pet owners to visit the veterinarian. Plaque and calculus formation with associated gingivitis are the most common clinical conditions diagnosed by veterinarians in dogs and cats of all ages. Why is the incidence of dental disease so high in our companion animals? Pets living longer may be one of the reasons that dental disease is prevalent. It may also be related to lack of owner education and compliance with at-home and professional veterinary dental preventative care.
Why is dog and cat oral health so important?
Owners often will not seek veterinary care for periodontal disease until they notice pain when touching the pet’s face; reluctance to eat or abnormal chewing; drooling; bleeding; food being dropped from the mouth; and/or halitosis. But, periodontal disease can be seen as early as 6 months of age, and by 3 years of age, most dogs and cats have evidence of periodontal disease. Dental issues in young dogs and cats can include retained deciduous teeth, supernumerary teeth, malocclusion and misalignment. These conditions, left unmanaged, can lead to overcrowding of the teeth and trauma to soft tissues and gums contributing to periodontal disease in the older pet.
Periodontal disease progresses if effective dental prophylactic therapy is not pursued. Advanced periodontal disease can cause the pet oral and systemic health problems including loose, broken or infected teeth; dental abscesses affecting tooth alveolus; mandible or maxilla osteomyelitis; and possible systemic infections or negative impact on organ function. Additionally, veterinary literature shows a correlation between the severity of periodontal disease in dogs and histopathologic changes in myocardial, renal and hepatic tissue. Oral pathologies cause pain for the pet with effects on appetite, behavior changes (irritability, socialization) and general morbidity.
How can we educate the pet owner about home health care?
Pet oral hygiene is accomplished through a combination of veterinary therapy and care at home. Owners should be educated about signs of dental problems, significance of periodontal disease, and importance of preventative care. Owner education starts in the exam room. It is important for the veterinarian to assess both the pet and owner when considering home dental care. Is the owner interested, committed and physically able to perform home oral care? Will the pet’s temperament allow home oral care? Prescribed home dental care will not work if the owner or pet are not compliant.
Showing the client changes in the pet’s mouth during the oral exam (tartar or plaque
accumulation, evidence of gingivitis, juvenile dental malformations) will help reinforce the need for preventative care. It is also important to show the owner how to train the pet to tolerate touching of the mouth and gums.
Prescribing dental home hygiene without showing the client how to proceed will increase noncompliance, so the veterinary team should demonstrate oral cleansing techniques to the owner. The veterinary team can demonstrate on one side of the pet’s mouth with a toothbrush, finger brush, swab or gauze. Observing the owner brushing the other side of the mouth provides an opportunity to offer brushing tips and suggestions.
Dental wash solutions or a dental diet may be a better oral care option for owners and pets that cannot use brushing tools. Not all commercial products that say “veterinarian recommended” are effective as dental aids. Clients can visit the Veterinary Oral Health Council website (www.vohc.org) for a list of independently evaluated dental products receiving their seal of approval as effective dental care aids.
How can we educate the pet owner about professional veterinary dental care?
With severe periodontal disease, professional prophylaxis may be necessary before prescribing home dental care. It’s important to educate the owner on the reasons for professional dental cleaning and the procedures used:
- Routine dental cleaning for pets with periodontal disease can prevent infections, pain and systemic illness.
- Professional dental cleaning is done under anesthesia to allow the veterinarian to examine the mouth, stage disease, determine the need for extractions, clean above and below the gum, and determine an appropriate home dental care plan.
- Dental X-rays, important to evaluate tooth roots and bone, must be done with anesthetic restraint.
Physical examination and lab profiling should be standard of care, especially for older pets to minimize risk of anesthesia. Fluid diuresis should also be considered depending on each pet’s medical condition. Explanation of the pet’s predental evaluation and dental procedure will help reassure the client about the need for anesthesia and allow the practice of the highest quality medicine.
How can we educate the pet owner about appropriate follow-up?
Dentistry should be part of a pet’s overall preventative health care plan starting with the first puppy or kitten visit. Evaluating dental health at each annual exam helps reinforce the importance of early preventative care and provides the opportunity to remind owners that periodontal disease progresses at the same rate in dogs and cats as in people.
In older pets, a dental recheck should be recommended 3 to 6 months following professional cleaning or after starting a home dental plan. For pets with other medical conditions, such as cardiac disease or renal insufficiency, frequent dental evaluation is appropriate. These evaluations give the veterinary team an opportunity to evaluate the effectiveness of the pet owner’s home dental care and to provide encouragement to continue.
By helping improve the overall health of each pet, veterinary dental care provides an important client and pet service as well as providing professional and financial rewards to the veterinary professional.
Antibiotic Use for Dental Surgeries
Michael Jennings, VMD, DAVDC
BluePearl in Philadelphia
One common question I often discuss with other veterinarians is when to use antibiotics with dental surgeries. The cases that warrant it are quite rare. A recent panel discussion at the Veterinary Dental Forum in Nashville1 also tackled the topic, and there are some important points impacting our use of antibiotics that are worth sharing:
- While much of the focus of antibiotic use in veterinary medicine has focused on food animals, recently there has been more attention on antibiotic use in companion animals.
- Transfer of drug-resistant bacteria from companion animals to pet owners and the impact on the wider community is being studied and acknowledged as a potential threat to public health.
- One of the biggest issues is inappropriate prescribing of antibiotics. Reasons are multiple and include demand from patients/patient owners, time pressure on physicians/veterinarians, and diagnostic uncertainty.
- Unfortunately, there is a tendency to use antibiotics as part of the management of any animal with periodontal disease or other oral condition, although there is no justification for this.
- It is imperative to review periodontal treatment strategies and determine whether systemic antibiotics have a role to play in the management of periodontal disease.
Periodontal disease is the most common oral condition we treat, and the process in dogs and cats is the same as in humans. Plaque accumulates > minerals in our saliva bind and convert it to calculus > mineralized layers of bacteria accumulate against and underneath the gumline > gingivitis develops > untreated gingivitis results in bone loss and periodontal pockets. Many of our animals – especially those without regular anesthetized cleanings and daily home care – will develop advanced periodontal disease, requiring surgery and extractions to remove the source of infection and inflammation.
With cases of advanced periodontal disease, are antibiotics necessary pre-op? Animals with severe disease have been living daily with their infection, often for years. If they are otherwise healthy, although their immune system has been in overdrive responding to the disease, it is able to maintain the animal’s health. Treatment of the disease with thorough cleanings and extraction of diseased teeth is the best way to reduce the bacterial load and give the immune system a break.
What about intra-op doses? Transient bacteremia does occur during dental surgeries. However, again, the immune system is there to quickly and efficiently clear the bloodstream, and it is not just surgery that causes bacteremia. Studies have also shown that humans with advanced disease will have significantly higher levels of circulating bacteria after brushing their teeth!2
Post-op? After the disease is treated, the body’s healing process is ready to take over. Due to its great vascularity, the oral cavity heals relatively quickly and efficiently, especially after the bacterial load has been decreased. Closing the extraction sites also promotes faster healing.
What if surgery isn’t an option? There are some cases when other systemic severe disease is present that precludes moving forward with a dental surgery. These cases are also rare. Contrary to previous recommendations, patients with heart murmurs or valve disease do not need prophylactic antibiotics. As we know that age is not a disease, don’t miss the chance to make your senior patient’s golden years a bit brighter with a healthier mouth. Some of my most rewarding cases have been older animals who are more alert, energetic and comfortable following treatment of their dental disease.
Are there cases when antibiotics should be used? Again, the number of cases are rare. Examples include animals with compromised immune systems (ex: uncontrolled diabetics, uncontrolled Cushing’s disease, patients receiving chemotherapy). In most of these cases, the underlying uncontrolled disease would likely warrant treatment priority over a dental procedure.
We must also manage the owners’ expectations. Many are surprised their pet is not prescribed an antibiotic following dental surgery. Antibiotics come with their own set of issues (side effects: nausea, vomiting, diarrhea) in addition to the larger public health threat. After an explanation of the cons of prescribing most often outweighing the pros, most are happy to forego trying to give another medication (in addition to pain control) following dental surgery.
- Reiter A, Harvey C et al. “Antibiotic panel.” Proceedings of the Veterinary Dental Forum. Sept. 2017, Nashville, TN.
- Tomas I, Diz P, Tobias A et al. “Periodontal health status and bacteraemia from daily oral activities: systematic review/meta-analysis.” J Clin Periodontol. 2012 Mar; 39(3); 213-28.
It may be time to start asking: “Does your dog hunt feral pigs?”
Lauren Harris, DVM, DACVECC
BluePearl in Clearwater FL
I don’t know about you, but the last time I had Brucella on my differential diagnosis list as a cause for pyothorax was…well, never. However, two BluePearl hospitals diagnosed Brucella suis in dogs with pyothorax last year. Brucella suis has not been previously reported as a cause of pyothorax in dogs.
The first dog was a 10 to 12-year-old spayed female pitbull mix. She was found as a stray in Hawaii in 2011 and shipped to Michigan for spay and adoption. While her full history was unknown, she was suspected to be a pig-hunting dog based on her scars and tattoos. In 2013, she was diagnosed with idiopathic chylothorax. After surgery and pleuroport placement, she did well for two years without recurrence of pleural effusion. In November 2016, chylous effusion returned. After a month of steroid therapy, the effusion became serosanguineous and was submitted for bacterial culture. The culture detected Brucella suis. It is suspected that this dog contracted B. suis in Hawaii while pig hunting, and had a subclinical infection. The patient was started on a 6-week course of doxycycline and enrofloxacin, and is currently under a lifelong quarantine agreement with the Michigan State Health Department.
The second case was recently treated at BluePearl Tampa. This dog is a 6-year-old castrated male Catahoula leopard dog. The dog was recently adopted, and had a known history of feral pig hunting. In late May 2017, he was medically managed with antibiotics and chest tube placement in Texas for a pyothorax. In June of 2017, he was seen by the emergency service at BluePearl Tampa for increased respiratory effort. A pyothorax was diagnosed, and exploratory surgery was elected. At surgery, a large volume of purulent effusion was noted in the chest as well as a cranial mediastinal granuloma/mass. During cranial mediastinal mass removal, the brachycephalic trunk was inadvertently ligated, and subsequently repaired. During repair, the patient experienced cardiopulmonary arrest, but was successfully resuscitated. While in surgery, the Texas veterinarian previously treating the dog called to report that the dog was culture positive for Brucella suis. Humane euthanasia was discussed, but declined by the owner. After two days, the patient started to experience swelling of the forelimbs, ventral neck, and head. Cranial vena cava syndrome (secondary to cranial vena cava clot or stricture) was considered. Additional surgical intervention was discussed but declined. After one week in the hospital, the owner removed the pet from the hospital against medical advice and the patient was lost to follow up. The cranial mediastinal mass histopathology was suspicious for a necrotic thymoma. During the course of his hospitalization, nine BluePearl Tampa employees were directly exposed to B. suis, seven of which were prescribed the CDC’s recommended six-week prophylactic antibiotic combination of doxycycline and rifampin. At the time of this writing, one associate has tested positive for B. suis.
Brucellosis is an infectious disease caused by Brucella, a gram-negative coccobacillus that can infect a variety of animal species and humans. Several species of Brucella exist which are based on host preference: Brucella abortus (cattle), Brucella canis (dogs), Brucella melitensis (goats, sheep), Brucella neotomae (rodents), Brucella ovis (sheep), and Brucella suis and its biovars (pigs, cattle, hares, rodents, and wild ungulates). In the past few years, the incidence of B. suis in dogs in certain parts of Australia increased 17-fold. Brucella suis is much less commonly diagnosed in the United States; however, the USDA APHIS diagnostic laboratory (in Ames, Iowa) documented a few cases of B. suis in dogs in the Eastern United States in 2017.
In the United States and Australia, feral pig hunting has been identified as the principal risk factor for canine brucellosis due to B. suis. Other possible causes for exposure may include ingesting raw feral pig meat or being exposed to other dogs used for feral pig hunting. In rare cases, there is no known risk factor. Humans may be exposed to B. suis by coming in contact with bodily fluids of infected dogs (including urine, saliva, reproductive materials, respiratory secretions or body cavity effusions). Laboratory personnel, slaughterhouse workers, meat-packing plant employees, and veterinarians are at highest risk of exposure. Because these organisms are zoonotic and a threat to human health, B. abortus and B. suis are reportable to public health in all states.
Clinical signs of B. suis in dogs most commonly include: fever, orchitis/epididymitis, back pain, lameness, abortion, enlarged lymph nodes, lethargy, and occasionally vomiting. It is estimated that up to 40% of serologically positive dogs have a subclinical infection (showing no clinical signs of illness). While not previously reported, these two cases demonstrate that Brucella suis may be isolated in pleural effusion.
Brucella suis should be considered as a differential in any dog with a history of exposure to feral pig hunting, or to other dogs that have previously hunted. In any case where Brucella is being considered, individuals working with these animals or lab samples should use personal protection equipment including gloves, disposable gown, facemask and eye protection. The use of good personal hygiene is also of great importance. Extreme caution and care should be used when treating wounds, collecting blood or other tissue samples, neutering/spaying, or handling any reproductive tissues including fetuses of possibly infected dogs. The animal should be kept in isolation. Brucella can survive for months in the environment, but is inactivated with autoclaving, commonly used hospital disinfectants, and by direct sunlight.
In cases where B. suis is considered a potential diagnosis based on risk factors and/or clinical signs, testing is available. The USDA APHIS diagnostic laboratory recommends that canines with exposure to suspected B. suis be screened with a card test (slide agglutination test) for B. abortus as it cross reacts with B. suis. If the card test is positive, serology, culture, and PCR for B. suis at the Ames laboratory is recommended. It is important to note that patients that have been recently infected with B. suis organisms may be serologically negative, and should be re-tested in 6 weeks. Agar gel immunodiffusion (AGID) or slide agglutination testing for B. canis is commonly available at most reference laboratories; however, this test is specific for B. canis and does NOT cross react with B suis.
Given the zoonotic potential of B. suis, euthanasia of affected dogs is recommended, but not mandatory. If euthanasia is not elected, combination therapy with doxycycline and rifampin seems to be effective, when combined with surgical resection of infected tissues. Affected animals should be isolated from other animals, and this quarantine is for the life of the pet. Serum biochemistry should be frequently rechecked due to the potential hepatotoxicity of rifampicin. Response to treatment can be monitored with recheck serology.
James DR, Golovsky G, Thornton JM, et al. Clinical management of Brucella suis infection in dogs and implications for public health. Aus Vet J. 2017; 95(1-2): 19-25.
Mor SM, Wiethoelter AK, Lee A, et al. Emergence of Brucella suis in dogs in New South Wales, Australia: clinical findings and implications for zoonotic transmission. BMC Veterinary Research. 2016;12(199): 1-9.
Woldemeskel M. Zoonosis due to Brucella suis with special reference to infection in dogs (carnivores): a brief review. Open Journal of Veterinary Medicine. 2013; 3: 213-221.
Ramamoorthy S, Woldemeskel M, Ligett A, et al. Brucella suis infection in dogs, Georgia, USA. Emerg Infect Dis. 2011; 17(12):2386-7.
Greene CE and Carmichael LE. Canine Brucellosis. In: Greene CE, editor. Infectious Diseases of the Dog and Cat. 4th ed. St. Louis: Saunders; 2012, pp. 398-411.
Pearls from the ACVIM Forum 2017
Jeff Dennis, DVM, DACVIM
BluePearl in Kansas
What dose of cosyntropin should be used to test patients for Addison’s disease?
Cortrosyn® is an expensive drug. Consequently, using a lower dose of the drug to test dogs for Addison’s disease would be desirable. Twelve dogs were tested for Addison’s disease. Blood samples collected pre- and 1 hour post-ACTH stimulation testing demonstrated that a 1 mcg/kg intravenous dose of Cosyntropin did not cause maximal adrenal response as did a 5 mcg/kg intravenous dose. The 5 mcg/kg intravenous dose is recommended for checking dogs for Addison’s disease. (Botsford-abstract)
Can you predict which diabetic cats can achieve remission?
Being able to predict which cats newly diagnosed with diabetes mellitus might be able to achieve remission of their condition would help with predicting treatment recommendations and prognoses. A European study of 583 cats with newly diagnosed diabetes mellitus found that cats that had received glucocorticoids within 90 days of starting insulin therapy were more likely to achieve diabetes remission. In addition, cats of the Burmese breed, compared to crossbreed cats, were more likely to achieve remission, suggesting the pathogenesis of their condition might be different than other cats. Overall 13.1% of the cats achieved remission within 1 year of starting therapy. Interestingly, cats with lower body weight at diagnosis had increased odds of death within 30 days of the diagnosis of diabetes mellitus. (Gostelow – abstract)
Is there a role for using corticosteroids in the treatment of pancreatitis?
Sixty-five dogs with pancreatitis were divided into two groups, one that received prednisolone (1 mg/kg/day) and one that did not receive prednisolone. IV fluid support and adjunctive therapy were pursued in all patients. The c-reactive protein value (a measure of inflammation), time to clinical improvement, length of hospitalization, and mortality rate were all significantly lower in dogs receiving prednisolone compared to those who did not. Corticosteroid therapy may play a role in treating dogs presenting with pancreatitis. (Okanishi – abstract)
Is the SDMA (symmetric dimethylarginine) value affected by the pet’s hydration?
The laboratory values of BUN and creatinine, which have historically been used to predict kidney function, are increased in the presence of dehydration. The SDMA concentration in the blood is achieving greater acceptance as an indicator for the early loss of kidney function. But is the SDMA value also affected by the pet’s hydration status? Sixty-nine dogs presenting with clinical evidence of dehydration had SDMA values checked prior to and then after rehydration. In 16 dogs, elevated SDMA values on initial labwork normalized after the patient was rehydrated. It was concluded that hydration status can affect the SDMA value. The SDMA concentration should be checked after correction of the patient’s dehydration to better reflect the patient’s underlying kidney function (Choi – abstract)
Is glargine or protamine zinc insulin (PZI) more effective for treating diabetes mellitus in cats?
Forty-six cats with recently diagnosed diabetes mellitus were randomly assigned to be treated with either glargine or PZI recombinant insulin administered BID. Cats with concurrent conditions were excluded from the study. Cats were transitioned to a low carbohydrate diet and fed with the goal of achieving an optimum weight. Insulin doses were adjusted using a single, nadir-focused protocol based on blood glucose results. The cats were monitored for 1 year. There was found to be no significant difference in mean blood glucose, fructosamine, BID insulin dose, quality of life score, or remission rate between the two insulins. The study did suggest that overweight cats that lost weight were more likely to achieve remission. The study indicated that glargine and PZI recombinant insulins produced comparable glycemic control and no detectable difference in remission rates in diabetic cats. (Gostelow – abstract)
Tanovea: An Advance in Canine Lymphoma Treatment
Stacy Santoro Binstock, DVM, DACVIM (Oncology)
BluePearl in Philadelphia
Lymphoma is one of the most common cancers diagnosed in dogs, and it seems to be increasing in frequency. It arises from a clinical expansion of lymphoid cells and is often classified based on location, phenotype (B- vs. T-cell lymphoma) and grade. The majority of dogs present with multicentric, high grade, B-cell lymphoma. Dogs with B-cell lymphoma have been shown to respond more favorably to chemotherapy for a longer duration of time when compared to dogs with T-cell lymphoma.
The most effective treatment option for canine lymphoma is systemic chemotherapy using a combination of multiple drugs, often referred to as a “CHOP” protocol, and there are a variety of published protocols in veterinary literature. Using a conventional CHOP-based protocol, approximately 80-95% of dogs will achieve remission with a median survival time of 12 months, and 20-25% will be alive 2 years after diagnosis. Even with a high likelihood of remission, the majority of dogs will relapse. At that time, a CHOP-based protocol may be re-instituted, or an alternative rescue protocol may be considered.
A new drug for canine lymphoma treatment has emerged on the horizon. This drug, rabacfosadine, or Tanovea-CA1TM, is produced by VetDC, Inc. and has been conditionally approved by the FDA. Tanovea is a prodrug that is converted within cells to an active phosphorylated metabolite called PMEG, which is a guanine analog. PMEG accumulates in lymphocytes and inhibits DNA polymerase, therefore affecting DNA synthesis and repair. PMEG is not utilized as a chemotherapeutic due to poor permeability and non-specific toxicity. Tanovea has been used to treat both naïve and relapsed canine lymphoma. It is administered as a 30-minute intravenous infusion every 3 weeks for 5 treatments and has been reported to induce remission in 77% of dogs with lymphoma; median remission duration is approximately 4.5 months. It is more likely to induce a response in naïve or minimally pretreated patients with B-cell lymphoma. Tanovea has a rapid onset of action, and most responses are noted within 7 days of treatment.
Tanovea is generally well-tolerated in clinical studies, and most adverse reactions that have been reported are mild. The most common adverse reactions include neutropenia, diarrhea, weight loss, lethargy and dermatopathy. These reactions were generally noted to be mild, transient, and manageable. A less frequent, but severe and sometimes fatal side effect is pulmonary dysfunction thought to be related to pulmonary fibrosis. It is not advised to administer Tanovea to West Highland white terriers, and it should be used with caution in other terrier breeds. Owners are advised to avoid direct contact with their pet for 5 days, and they should wear chemotherapy resistant gloves when handling their pet’s urine, feces, vomit or saliva.
Tanovea offers an exciting, promising new treatment option for naïve and relapsed canine lymphoma. It is a safe option with a reasonable expectation for efficacy.
- Withrow & MacEwen. Small Animal Clinical Oncology 5th edition. Saunders, Elsevier Inc., 2013.
- Vail DM, et al. Assessment of GS-9219 in a Pet Model of Non-Hodgkin’s Lymphoma. Clin Cancer Research. May 2009; 15 (10): 3503-3510.
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