Monthly Update

Issue Contributors: Kenneth Palladino Jr., DVM, Practice Limited to
Internal Medicine @ CCVS
Editor: William B. Henry DVM, DACVS

December 2013

WHAT'S THE SCOOP WITH THAT POOP?

CANINE PARVOVIRUS PART 2

Kenneth Palladino Jr., DVM

This article is the second part of "What's the Scoop with that Poop? - Canine Parvovirus." Last month, the history of the discovery and evolution of Canine Parvovirus as well as its epidemiology were presented. Clinical signs of the virus were also covered. This month's article will describe both general and more specific diagnostics related to Canine Parvovirus, and conclude with treatment options, markers for prognosis and preventative techniques.

GENERAL DIAGNOSTICS:

Though there may be a high suspicion for parvovirus it is important to remember other possible differential diagnoses. Other enteric viruses may cause similar clinical signs such as Coronavirus. Intestinal parasites, foreign material and intussusception must all be considered. A fecal flotation test and Giardia ELISA should be performed to help rule out concurrent internal parasites. (Figure 9) If a positive test result is found proper therapy should also be prescribed as soon as possible. Routine diagnostic testing should be performed on presentation starting with a CBC and chemistry panel. Radiographs and an abdominal ultrasound could also be considered.

For more on General Diagnostics CLICK HERE.

DEFINITIVE DIAGNOSTICS:

Definitive diagnosis of Canine Parvoviral Enteritis requires detection of the virus in feces, serology and/or necropsy with histopathology. The Parvo Snap Test is the most widely used assay for the diagnosis of canine parvovirus. (Figure 11) It is an in-house fecal antigen ELISA which is performed on a rectal swab specimen. There are several types of this test available from different companies. All detect variants of Canine Parvovirus-2, including 2c but their sensitivities and specificities vary. In general these tests are regarded as accurate and specific. Sensitivity of the tests can be problematic due to transient viral shedding. Antibody present in the sample may also bind potentially available antigen resulting in a false negative result. It has also been suggested that a false positive result can occur several days to a couple weeks after vaccination with a modified live preparation.

For more about Definitive Diagnostics CLICK HERE.

TREATMENT OPTIONS:
Fluid Therapy: Once positively identified, therapy for Canine Parvovirus can become intensive as these patients are often in critical condition. The mainstay of therapy is supportive care and treatment of potential secondary bacterial infections. Most cases should be placed in isolation. Due to the large amount of fluid losses most patients will be hypotensive and require immediate fluid resuscitation. Fluids are one of the cornerstones of therapy for parvovirus. Ideally they should be administered intravenously. Some pets are so hypovolemic that an intraosseous approach may be necessary.

For more on Fluid Therapy CLICK HERE.

Monitoring of electrolytes and more importantly the blood glucose concentration is essential. Lack of nutrition, poor absorption and losses secondary to diarrhea and vomiting can lead to hypokalemia and hypoglycemia. Potassium chloride supplementation and dextrose supplementation through the IV fluids is often required. Normalizing the glucose concentration has been shown to be a critical step in patient care for many diseases. A central line placement may be beneficial for sampling, fluid administration, monitoring of central venous pressures.

Antibiotic Therapy: Antibiotic therapy is needed to help resolve secondary bacterial infections from translocation. Antimicrobial drugs with activity against gram-negative and anaerobic bacteria should be chosen, and are best if administered intravenously.

For more on Antibiotic Therapy CLICK HERE.

Antacid and Antiemetic Therapy: Symptomatic therapy for Canine Parvovirus also includes use of antacids and antiemetic medications. Antacid therapy can be in the form of H-2 blockade with injectable famotidine or proton pump inhibition with injectable pantoprazole. Metoclopramide should be used with caution due to its pro-motility effects as there is a risk of causing an intussusception in the diseased intestinal tract. This makes drugs such as maropitant and ondansetron more appealing.

Enteral Nutrition: Use of antiemetic therapy will help reduce nausea and vomiting which can potentially help increase appetite. This is important because research has concluded that early enteral nutrition is, "the most important stimulus for intestinal growth, repair, and integrity is the presence of nutrients within the gut lumen." The absence of nutrients can lead to further villous atrophy and suppression of crypt cell proliferation. Enteral nutrition is superior to starvation or even total parenteral nutrition in critical illness associated with gut-barrier dysfunction. Appetite has been shown to improve faster with enteral nutrition compared to an NPO group. Earlier repair of the epithelium may also lead to a decrease in bacterial translocation. Placement of a nasoesophageal or nasogastric feeding tubes should be considered as a first line therapy to provide enteral nutrition. Surgical placement of an esophageal feeding tube or PEG tube should be avoided if possible in the critically ill patients.

Other Investigated Therapies: There are several other treatments that have been studied for use in parvoviral enteritis. Anti-endotoxin sera, recombinant bactericidal permeability-increasing factor, recombinant granulocyte colony-stimulating factor and recombinant feline interferon-omega are some of the more novel therapies that have been researched. Most of these have not been

shown to be beneficial in treatment of the disease. Oseltamivir (Tami-Flu) has also been proposed as a treatment for Canine Parvovirus. The use of oseltamivir remains speculative. (Figure 13) There is concern over how much of the drug is actually absorbed when administered orally to patients with a compromised gastrointestinal tract. A larger concerns lies in the use of a medication that is designed and regulated for use in treating human influenza. Overuse in veterinary medicine could select for resistant influenza viruses resulting in a human pandemic. For now, most researchers agree that this product should not be used for treatment of Canine Parvovirus.

For more on Other Instigated Therapies CLICK HERE.

PROGNOSIS AND PREDICTORS OF SURVIVAL:
The prognosis for recovery varies with the severity of illness, the owner's financial constraints and the overall viral load per patient. Survival rates of greater than 90% have been reported with aggressive treatment at tertiary referral hospitals. Historically a more severe infection, leukopenia and hypoalbuminemia have all been associated with high mortality rate in multiple studies.

For more on Predictors of Survival CLICK HERE.

PREVENTION:
Prevention of contracting Canine Parvovirus-2 center around limiting exposure of non-vaccinated or partially vaccinated puppies to infected areas. Proper quarantine of newly acquired animals up to two weeks, isolation techniques, cleaning and disinfection all contribute to prevention.

For more on Prevention CLICK HERE.

IMMUNITY AND VACCINATION:

Immunity either through survival of natural infection or vaccination remains one of the most important means of preventing spread of the disease. Immunity acquired from surviving a natural infection is thought to be life-long. Both live and modified-live (attenuated) vaccines are available. The modified-live Canine Parvovirus-2 vaccine is used most often. (Figure 14) The killed vaccine provides less duration of immunization but may be recommended in pregnant dogs and puppies less than 5 weeks of age. Use of the attenuated vaccines in pregnant bitches could cause infection of the puppies in utero. The low passage, high-titer vaccines are considered the most effective.

Vaccination protocols state that the series should be begun at 6 to 8 weeks of age. The puppy should receive a booster every 3 to 4 weeks until no sooner than 16 to 18 weeks of age. A longer course up to 20 to 22 weeks of age is recommended in breeding kennels and in some of the more susceptible breeds of dogs. Then another booster should be administered at 1 year of age and then every 3 years. Puppies should be quarantined at home for 7-10 days after the last booster vaccine is administered as there can be shedding of the virus in feces.

On a final note, Canine Parvovirus variants do not infect humans. Though people can spread the disease on clothing and hands, infection does not develop in the human population. Good hygiene practices are still encouraged as there are other zoonotic infections that cause similar clinical signs in puppies. Some of these can be seen as co-infections with Canine Parvovirus.

References:

Sykes, Jane E. "Canine parvovirus infections and other viral enteritides" Canine and Feline Infectious Diseases. Ed. Jane E. Sykes. St. Louis: Elsevier Saunders. 2013. 141-151.

Li L, McGraw S, Zhu K, et al. Circovirus in tissues of dogs with vasculitis and hemorrhage. Emerging Infectious Diseases. 2013 April; 19(4):534-541.

Lamm CG, Rezebek GB. Parvovirus infection in domestic companion animals. Veterinary Clinics Small Animal Practice. 2008; 38:837-850.

Carmichael LE. An annotated historical account of canine parvovirus. Journal of Veterinary Medicine Series B. 2005; 52:303-311.

Prittie J. Canine parvoviral enteritis: a review of diagnosis, management, and prevention. Journal of Veterinary Emergency and Critical Care. 2004; 14(3):167-176.

Bird L, Tappin S. Canine parvovirus: where are we in the 21st century? Companion Animal. 2013 June; 18(4):142-146.

Kapil S, Cooper E, Lamm C, et al. Canine parvovirus types 2c and 2b circulating in North American dogs in 2006 and 2007. Journal of Clinical Microbiology. 2007 December; 45(12): 4044-4047.

Hong C, Decaro N, Desario C, et al. Occurrence of canine parvovirus type 2c in the United States. Journal of Diagnostic Investigation. 2007;19:535-539.

Haligur M, Ozmen O, Sezer K, et al. Clinical, pathological and immunohistochemical findings in diarrgeic dogs and evaluation of canine parvoviral and coronoviral enteritis. Journal of Animal and Veterinary Advances. 2009; 8(4):720-725.

Godsall SA, Clegg SR, Stavisky JH, et al. Epidemiology of canine parvovirus and coronavirus in dogs presented with severe diarrhoea to PDSA PetAid hospitals. Veterinary Record. 2010; 167:196-201.

Stander N, Wagner WM, Goddard A, et al. Ultrasonographic appearance of canine parvoviral enteritis in puppies. Veterinary Radiology & Ultrasound. 2010; 51(1):69-74.

Schulz BS, Strauch C, Mueller RS, et al. Comparison of the prevalence of enteric viruses in healthy dogs and those with acute haemorrhagic diarrhoea by electron microscopy. Journal of Small Animal Practice. 2008; 49:84-88.

Markovich JE, Stucker KM, Carr AH, et al. Effects of canine parvovirus strain variations on diagnostic test results and clinical management of enteritis in dogs. Journal of the American Veterinary Medical Association. 2012; 241(1):66-72.

Hirasawa T, Yono K, Mizazuki K. Detection and genomic analysis of canine parvovirus by the polymerase chain reaction. Journal of Veterinay Medicine Series B. 1996;43:545-554.

Esfandiari J, Klingeborn B. A comparative study of a new rapid and one-step test for the detection of parvovirus in faeces from dogs, cats and mink. Journal of Veterinary Medicine Series B. 2000;47:145-153.

Elia G, Cavalli A, Cirone F, et al. Antibody levels and protection to canine parvovirus type 2. Journal of Veterinary Medicine Series B. 2005;52:320-322.

Pratelli A, Cavalli A, Normanno G, et al. Immunization of pups with maternally derived antibodies to canine parvovirus (cpv) using a modified-live variant (cpv-2b). Journal of Veterinray Medicine. 2000;47:273-276.

Lechner ES, Crawford PC, Levy JK, et al. Prevalance of protective antibody titers for canine distemper virus and canine parvovirus in dogs entering a Florida animal shelter. Journal of the American Veterinary Medical Association. 2010;236(12):1317-1321.

Schoeman JP, Goddard A, herrtage ME. Serum cortisol and thyroxine concentrations as predictors of death in criticallt ill puppies with parvoviral diarrhea. Journal of the American Veterinary Medical Association. 2007;231(10)1534-1539.

Mohr AJ, Leisewitz AL, Jacobson, LS, et al. Effect of early enteral nutrition on intestinal permeability, intestinal protein loss, and outcome in dogs with severe parvoviral entertitis. Journal of Veterinary Internal Medicine 2003; 17:791-798.

Goddard A, Leisewitz AL, Christopher MM, et al. Prognostic Usefulness of blood leukocyte changes in canine parvoviral enteritis. Journal of Veterinary Internal Medicine. 2008;22:309-316.

Yilmaz Z, Senturk S. Characterization if lipid profiles in dogs with parvoviral enteritis. Journal of Small Animal Practice. 2007;48:643-650.

Kocsturk M, Martinez S, Eralp O, et al. Prognostic value of serum acute-pahse proteins in dogs with parvoviral enteritis. Journal of Small Animal Practice. 2010;51:478-483.

Duffy A, Dow S, Ogilvie G, et al. Hematalogic improvement in dogs with parvovirus infection treated with recombinant canine granulocyte-stimulating factor. Journal of Veterinary Pharmacology and Therapeutics. 2010;33:352-356.

Mantione NL, Otto CM. Characterization of the use of antiemetic agenst in dogs with parvoviral enteritis treated as a veterinary teaching hospital: 77cases (1997-2000). Journal of the American Veterinary Medical Association. 2005;227(11):1787-1793.

Bragg RF, Duffy AL, DeCecco FA, et al. Clinical evaluation of a single dose of immune plasma for treatment of canine parvovirus. Journal of the American Veterinary Medical Association. 2012;240(6):700-704.

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In This Issue

Canine Parvovirus Part 2

Wellness Practice Educational Tips

Previous Tech Tips

Newsletter Archive

CT Scan Diagnostic

CCVS CT Scan Hours:

8:00 AM-6:00PM 7 days a week. 1-800-457-4900

The breakdown of CT charges are as follows:

1. CT Scan, In patient $905.00 (case already hospitalized at CCVS or referred to CCVS for work up and treatment and has a CT scan)

2. CT Scan, Additional image (if you add an additional scan site $300.00)

3. CT Scan, Out patient $985.00 **(case sent to CCVS exclusively for a CT; this includes charges for doctor overseeing case, IV catheter, and fluids post CT).

4. CT "Met Check" $590.00

5. CT STAT fee, $50.00 (on top of whatever you are doing).

These charges cover the CT, the contrast, radiologists read, rapid infuser, sevo anesthesia, and technician fee if we need to call someone in for the CT. It does not cover injectable drugs, if needed for IV anesthesia; estimated additional cost $50.00-$75.00.

_______________________

This month's CT Scan Diagnostics demonstrates the superior value of the CT alone or combination of myelogram/CT diagnostic value over radiography or myelography alone, in pre-operative diagnosis of cervical spinal cord disease. One realizes how un-prepared we were in the past, when using radiographs or myelograms alone, for diagnostics or pre-operative preparation. Pre-operative CT/myelograms have become standard of care in veterinary neurosurgery. They are very quick scans (5 minutes), very diagnostic, and much less expensive than high field (1.5 Tesla) MRI scans. There are very few high field MRI units ie. high quality imagery, very fast scan (25-30 minutes), in veterinary medicine, because of their initial cost and annual maintenance cost.

See CT Scans >>

Business Tip

Up until last year we provided our employees discounted veterinary care for their own pets, as all veterinary practice owner's have done for years. In our four practices, with over 100 employees, this represents many thousands of dollars every year. We decided to provide subsidized Trupanion insurance for our employees at our largest practice, CCVS, as a test to compare to previous years cost. As we did it I sent my idea to Trupanion hoping they would consider it for all the reasons enumerated in this promotion and perhaps provide a favorable rate for ourselves and our veterinary colleagues, if they elected to implement it. What better way to market their insurance program. Trupanion liked the idea!

Read the Trupanion Employee Advantage brochure

Tech Tip

OH, SEW EASY: UNDERSTANDING SUTURE MATERIALS was written by an LVT and given at the 2013 ACVS Symposium Technician's Seminar. The early 1900s of "silk and catgut" have changed dramatically with the advent of synthetic suture materials. Since 1960, many new types of suture material have become available. This discussion outlines the many types and applications of these synthetic suture materials. I have divided it into two parts. Part 1 discusses their use and general application. Part 2 discusses the specific types and application.

Read Part 1: Oh Sew Easy: Understanding Suture Materials >>

Continuing Education Opportunies

All our lectures provide 2 hours of Continuing Education Credits. You can register online through our websites, Boston Veterinary Specialists and

Cape Cod Veterinary Specialists. A meal is provided during each lecture. Your technicians are welcome as well.

Watch upcoming newsletters for future dates.

Wellness Practice Newsletters

Editors note:

Dr. Beverly Mason, Medical Director for our two general practices, writes a monthly newsletter that is emailed to our clients and printed for a handout to clients coming into the practices. They have been copied, pasted and passed around on the Internet. They are very concise, informative, and seasonally appropriate topics. Our general practice technicians find them helpful to educate their clients in the office and the email version gets very positive feedback on our Facebook and Yelp accounts. We thought you might like to use them in your own practices and will provide them to you each month.