This month’s survey question

Thank you for responding to our January survey! Here are the results:

All signs point to an increase in in-house diagnostics

Of those who responded to our January survey on in-house diagnostics, a full 66% expressed high interest in increasing their in-house diagnostic capabilities. Another 31% of respondents were also interested, leaving only 4% satisfied with their current level of in-house capabilities.

Current trends are toward increasing in-house diagnostic capabilities for more immediate information. Quick and easy access to diagnostic results allows practitioners to provide their patients and clients with more immediate answers and to begin treatment during the first visit to the clinic. This kind of service makes life easier for everyone—especially for the patients whose care can begin right away. In-house diagnostics also allow practices to easily perform rechecks and monitor their patients’ treatments to ensure dosages and medicines are working as expected.

There are many options for in-house diagnostics, and IDEXX has a full range of diagnostic instruments and services. The IDEXX VetLab^® Suite offers comprehensive capabilities, including hematology, chemistry, electrolytes, urinalysis, endocrinology, blood gases and infectious diseases. IDEXX also offers world-class customer and technical service, educational services and help from expert pathologists for consultations on difficult cases.

To learn more about the IDEXX VetLab Suite and other services, call us at
1-800-355-2896 or visit us on the Web at www.idexx.com/vetlab.

Chemistry • Hematology • Urinalysis • Electrolytes • Endocrinology • Coagulation • Blood Gas

Featured case study:
4-year-old neutered male shar-pei, Raisin
by Suzanne M. Pratt¹, DVM, DABVP; John A. Christian¹, DVM, PhD; Rose E. Raskin¹, DVM, PhD, DACVP; Margaret A. Miller¹, DVM, PhD; and Anne E. Brown², Department of Comparative Pathology¹ and Clinical Sciences², Purdue University School of Veterinary Medicine, West Lafayette, Indiana 

Detailed history
Two days prior to presentation to the PUVTH, the owner noticed that the dog’s skin was yellow. The referring veterinarian performed blood work that revealed elevated liver enzymes and renal parameters (specifics unknown) and referred the client. There is no history of abnormal urination or drinking, although the dog is a picky eater and has only one meal per day in the evening. Approximately once a month the dog has soft stools. The dog is on monthly heartworm preventive (Interceptor) year-round. Vaccination history is reportedly up-to-date. There is no history of travel and there are no other pets in the home. Recently, the dog has shown a decreased activity level.

Physical exam
Raisin was slightly dehydrated and no other significant physical exam abnormalities were identified beyond the clinical icterus.

Differential diagnoses
With the relatively sudden onset of icterus, the initial diagnostic list is focused on primary and secondary hepatic disease as well as possible acute hemolytic disease.

Plan
Because of the limited clinical picture, collection of a minimum data base with a complete blood count (CBC), clinical chemistry profile and urinalysis was deemed essential to help localize primary and potential secondary organ system involvement. These data will influence further diagnostic testing decisions.

Laboratory data

Morphology comments: Adequate platelets, enlarged platelets, anisocytosis 1+, slight icterus

Erythron—There is a very mild increased RBC count associated with a slightly decreased MCV (microcytosis). Microcytosis is most commonly seen with developing or well-established iron deficiency anemia as well as with hepatic insufficiency. The lack of any significant polychromasia and low normal to decreased hematocrit suggest underlying liver disease. No significant morphologic change such as acanthocytosis is seen for further support.

Leukon—Normal.

Thrombon—There is no quantitative platelet abnormality, but the presence of enlarged platelets may suggest a bone marrow response to a peripheral demand for platelets. Consideration for shortened platelet lifespan, as might be seen with peripheral consumptive processes (inflammation, coagulation, etc.), should be made.

Morphology comments: Moderate icterus

Kidney panel—There is mild azotemia (decreased GFR) with inadequate urine concentration (SG = 1.014 indicating tubular dysfunction) consistent with renal azotemia. There is potentially a mild prerenal component to the azotemia contributed by dehydration (hyperproteinemia, high normal albumin and sodium). There is no evidence to support a postrenal mechanism.

Electrolyte and acid-base profiles—Most electrolytes are within reference values. However, the mild elevation of TCO₂ and moderate decrease in chloride relative to sodium provides evidence of metabolic alkalosis. Relative chloride loss is most commonly due to upper GI loss or sequestration, although there is no current clinical support for this. Loss secondary to renal disease should also be considered.

Additionally, the anion gap is mildly elevated, which suggests a titrational metabolic acidosis; however, the TCO₂ is not decreased accordingly. This suggests that the alkalosis is predominant. An increase in uremic acids (renal azotemia) is the most likely cause of the increased anion gap. Other major differentials for a high anion gap include lactic acidosis, ketoacidosis and ethylene glycol or salycilate intoxication. None of these are likely, based on laboratory and clinical information.

The urine pH (6.5) in the face of a predominant metabolic alkalosis (based on elevated TCO₂) raises concern that there may be a paradoxical aciduria. Additional support for this concern includes a mild state of dehydration providing a drive to retain sodium in combination with a relative decrease in chloride. When chloride is depleted, the kidneys reabsorb bicarbonate in place of chloride, leading to lowering of urine pH. Although serum potassium is within reference limits, serum values are often a poor reflection of intracellular stores. It is possible that alkalosis could be driving potassium intracellularly leading to an increase in extracellular hydrogen ions. Hydrogen ions could then be excreted in the urine instead of potassium.

Hepatobiliary profile—A mild increase in ALT indicates hepatocellular injury. The moderate increase of ALP could indicate cholestasis or induction of the glucocorticoid isoenzyme. There is no other evidence to support a glucocorticoid response (normal leukogram, normoglycemia) and no history of steroid or anticonvulsant administration. Additionally, the moderate bilirubinuria (2+, SG = 1.014) supports cholestasis. The total bilirubin is mildly elevated and attributed mostly to an elevation of the delta bilirubin, which provides evidence for previous cholestasis.

Most parameters affected by functional hepatic mass are unremarkable. These include urea (increased), glucose, albumin, cholesterol and unconjugated bilirubin. In addition, no coagulation parameter (PT, PTT) abnormalities were observed. However, microcytosis without other clinical or laboratory evidence for iron depletion raises some concern for decreased functional mass.

Protein profile—There is a mild increase in total protein. In light of the mild clinical dehydration noted and the finding of a high within reference interval albumin and sodium, dehydration may be contributing to this increase. However, the degree of increase in globulin along with a low within reference interval albumin:globulin ratio are supportive of systemic antigenic stimulation/inflammation. A combination of processes is likely.

Interpretations

1. Renal azotemia (± prerenal due to dehydration)
2. Mixed acid-base disorder with a predominant metabolic alkalosis and titrational metabolic acidosis (secondary to azotemia)
3. Possible paradoxical aciduria
4. Mild hepatocellular injury, cholestasis and subtle evidence for decreased functional mass

Additional tests to be considered

1. Blood gas analysis to better characterize the acid-base disturbance
2. Additional evaluation of hepatic function:

1. Ammonia level determination would be ideal, with consideration for conducting an ammonia challenge test
2. Bile acids may be difficult to interpret due to concurrent cholestasis

3. Serum protein electrophoresis to allow accurate assessment of protein changes
4. Leptospirosis titers since both renal and hepatic disease are suggested
5. Fine needle aspirates and/or biopsies of liver and/or kidney

Primary differential—For a young shar-pei with evidence of hepatorenal disease, systemic amyloidosis, familial or reactive, is the working differential.

Further diagnostics

Diagnostic imaging findings—Hepatosplenomegaly was revealed with abdominal radiographs. No ultrasound abnormalities were observed and a guided liver biopsy was collected.

Diagnostic cytology—Impression smears of liver biopsy were highly cellular and primarily contained blood and hepatocytes that often had intracytoplasmic bluish-black pigment material consistent with lipofuscin. Benign hepatocellular hyperplasia was suggested based on the finding of mild to moderate anisocytosis, anisokaryosis and variation in N:C ratios. Occasional binucleation is seen. There are several bile canalicular casts between hepatocytes. Intermixed between hepatocytes there are moderate to abundant quantities of a bluish amorphous to fibrillar product consistent with amyloid. No infectious agents, significant inflammatory process or evidence of neoplasia is seen.

Interpretation

Extracellular proteinaceous product most consistent with amyloid, mild hepatocellular hyperplasia, cholestasis.

Figure 1: Impression smear from a shar-pei with hepatic amyloidosis. Bluish amorphous to fibrillar material in the center and top center is amyloid. The dark black-green material is bilirubin accumulation due to the cholestasis. The binucleate cells are consistent with hyperplasia. Few cells contain dark pigment consistent with lipofuscin. Wright’s stain, 100x objective field of view

Histopathology findings—Hepatic amyloidosis

Clinical case outcome
This dog had been diagnosed with shar-pei fever at 12 weeks of age based on episodic fevers with swollen hocks and an arched back. The patient was discharged from the PUVTH with prescriptions for colchicine to slow the progression of the disease and deracoxib (Deramaxx) for periodic fever and swollen joints.

Blood work performed by the referring DVM one month postdischarge showed moderately elevated alkaline phosphatase similar to the PUVTH results. He also had a minimally elevated creatinine (1.9, reference interval 0.5–1.8 mg/dL) and urea within the reference interval (15, reference interval 7–27 mg/dL). The dog has been on a low-protein diet, which could explain the urea value being relatively lower than the creatinine.

During the nine months postdischarge, the dog has had one notably bad episode of fever and swollen hocks at four months and weekly fever/swollen hock episodes once a week for the last four weeks. The referring veterinarian has increased the minimal Deramaxx dosage. Additional blood work is planned during the dog’s annual exam within the next six months unless there is a more immediate need prior to that.

References

1. DiBartola SP, Tarr MJ, Webb DM et al. Familial renal amyloidosis in Chinese Shar Pei dogs. J Am Vet Med Assoc. 1990;197:483–487.
2. May C, Hammill J, Bennett D. Chinese Shar Pei fever syndrome: a preliminary report. Research in Veterinary Science 1992;53:319–320.
3. Loeven KO. Hepatic amyloidosis in two Chinese Shar Pei dogs. J Am Vet Med Assoc. 1994;204:1212–1216.
4. DiBartola SP, Tarr MJ, Parker AT et al. Clinicopathologic findings in dogs with renal amyloidosis: 59 cases (1976–1986). J Am Vet Med Assoc. 1989;195:358–364
5. Flatland, B., Moore, R. R., Wolf, C. M., Yeomans, S. M., Donnell, R. L., Lane, I. F., Fry, M. M. VCP, 2007; 36: 105-108. Liver aspirate from a Shar Pei dog

The recommendations contained in Diagnostic Edge educational materials are intended to provide general guidance only. As with any diagnosis or treatment, you should use clinical discretion with each patient based on a complete evaluation of the patient, including history, physical presentation and complete laboratory data. With respect to any drug therapy or monitoring program, you should refer to product inserts for a complete description of dosages, indications, interactions and cautions.

Tell us what you think of this case, or let us know if you have a case that you would like to submit. E-mail us at diagnosticedge@idexx.com to get the process started.

IDEXX Learning Center

The IDEXX Learning Center provides knowledge you can put into practice. Take part in the evolution of animal diagnostics through an ongoing educational partnership with leading veterinarians from across the globe and take advantage of a wide range of education resources, reference materials and events. Visit the IDEXX Learning Center to see a full listing of available Webinars, seminars and online training courses from IDEXX.
 

Create your own account on the IDEXX Learning Center and see how IDEXX can help you reach your educational goals!

Here are some of the opportunities available this month:

Seminars Advances in Diagnosis and Management of Canine Pancreatitis Dr. Lisa Paull   The Most Commonly Misdiagnosed Diseases in Veterinary Medicine Dr. Fred Metzger   Tick-Borne Diseases in Dogs—An in-depth review of ehrlichiosis, babesiosis and Lyme borreliosis Dr. Rick Alleman

Webinar Safe Start: The Value and Importance of Preanesthetic Testing Ernie Ward, DVM

Spotlight on Nicki Brentin, LVT

A three-time weekly winner in our Suite Stories contest for her stories about Zena the cat, Chewy the rottweiler and Bailey the schnauzer, Nicki also became a finalist for her Zena story!

Nicki has been a technician for five and a half years. She currently works at the Puget Sound Veterinary Referral Center/Animal Emergency Clinic, which employs 12 veterinarians and more than 25 full- and part-time technicians. It’s a busy place, and even busier during the evenings and on weekends, with anywhere from 5 to 25 patients coming in during each shift.

Nicki feels that without a doubt, her clinic will increase its use of in-house diagnostics over the next few years. “The demand for in-house diagnostic work is becoming huge. If an animal comes in at 2:00 a.m., we want to know what’s wrong by 3:00 a.m. The more we can do in-house, the better we can serve our patients and clients.”

Nicki feels that pet owners compare their pets’ care to the care people get when they go to their own doctors. “You get everything done right away in human medicine, so clients expect to be able to get everything done for their pet in one building and get everything back quickly. In-house diagnostics allow us to offer better, higher quality service. It helps our reputation, too. A higher level of patient care makes clients happy, and happy clients tell their friends.”

“In-house diagnostics make our business more profitable, too. We can offer better, higher quality service and we can charge for it. We generally use outside laboratories for pathology, histopathology, etc. Our board-certified surgeons will send out tissue samples and our neurologist sends out cerebral spinal fluid for analysis. The doctors may occasionally do a recheck, too. But we rarely send out panels—we do them in-house because we can.”

Nicki describes herself as “one of those crazy vet techs whose life revolves around her pets,” all of which were owner-relinquished or abandoned at the clinic. Her lucky pets include Eddy, a five-year-old rottweiler mix; Isadora “Dori,” a four-year-old terrier mix; Murray, an eight-year-old border collie mix; and a few cats to round out the household.

IDEXX is dedicated to investing in research and development in order to offer veterinarians innovative tools and technologies that continue to improve your ability to provide patients with the highest level of care. Some of our most recent offerings from the past year include:

IDEXX VETLAB® INNOVATIONS

Catalyst Dx™ Chemistry Analyzer—Coming 2008

• Results in less time than it takes to prepare a sample to send out—Chem 22 in 8 minutes
• Run lab work immediately with preloaded CLIPs
• Multiple-patient load and go—4 Chem 10s in 18 minutes
• Onboard whole blood separation

SNAPshot Dx™ Analyzer—Coming 2008

• Immediate results to manage common diseases
• Run multiple patients at the same time
• Trusted SNAP® ELISA technology

Coag Dx™ Analyzer

• Immediate coagulation information
• Four veterinary-specific cartridges
• Fresh or citrated whole blood for PT and aPTT results

New for the VetStat® Electrolyte and Blood Gas Analyzer

• Multipack contains six each of the most used cassettes

New for the VetTest® Chemistry Analyzer

• New pipette tips for better sample flow
• Easy-open slides and no slide warm-up
• VetTest® Certificate Course at www.idexxlearningcenter.com at no cost!
• Avian profile, Diagnostic Health Profile and NSAID Panel

New for the IDEXX VetLab® Results Report with IDEXX VetLab® Station

• Fully integrated report shows results of all analyzers plus SNAP® test results
• Prior results column for easy comparison
• Reference ranges printed on report, including T₄
• Quicker identification of organ-specific abnormalities

IDEXX REFERENCE LABORATORIES INNOVATIONS

• IDEXX RealPCR™ tests offer definitive answers through accurate, fast real–time PCR

IDEXX SNAP® INNOVATIONS

• SNAP® cPL™ (canine pancreas-specific lipase) Test provides immediate answers pet-side for canine pancreatitis
• SNAP® 4Dx® Test supports pet owner education for heartworm and tick-borne disease prevention by screening for heartworm disease and three different tick-borne diseases

IDEXX DIGITAL INNOVATIONS

• IDEXX-PACS™ 3.0 software will increase your digital imaging diagnostic capabilities

IDEXX EQUINE INNOVATIONS

• IDEXX EquiView® All-Terrain-Grade Digital Imaging System
• New equine specialty tests from IDEXX/EBI®
• Equine Herpesvirus Type 1 (EHV-I)
• West Nile Virus
• Lyme disease and Anaplasma phagocytophilum

IDEXX CORNERSTONE® INNOVATIONS

• In-house/reference laboratory requests, results and trending data automatically downloaded to patient records
• Order, track and record patient treatments more efficiently with an integrated electronic whiteboard
• New inventory management capabilities with advanced bar-coding functionality
• LabREXX® test order forms ensure test orders are accurate

IDEXX INTEGRATED PRACTICE

• Enabled by SmartLink™ technology, the IDEXX Integrated Practice links and automates equipment, services and data for exceptional levels of medical care, productivity and profitability
• Maximize patient care
• Capture missed charges
• Automate and simplify tasks
• Empower staff

IDEXX LEARNING CENTER

• Online courses—Individual, self-paced courses that you can take anytime, anywhere
• Webinars—Online group learning events that you join at a set time
• Local seminars—Group learning events at a set time and place
• Conference education—Breakout sessions at local and national veterinary conferences
   

New Update to dogsandticks.com

dogsandticks.com, the dog owner education Web site, has been updated. Visitors will find:

• Updated local prevalence maps for Lyme disease, ehrlichiosis, anaplasmosis and heartworm disease
• New, owner-friendly education on preventatives and vaccines
• Stories from dog owners about their experiences with tick-borne diseases

Help your clients learn more about tick-borne diseases and stay up to date with the latest updates on emerging diseases.

With FREE Continuing Education Credit!*

NOW Approved in the United States, Australia and parts of Canada!†

Have you taken advantage of every qualifying Interactive Challenge for FREE continuing education (CE) credits?

Every Interactive Challenge from June 2006 on has each been worth 0.5 continuing education credit in the United States—and you get the credit just for participating! Check out the Diagnostic Edge archive and take any qualifying challenges you may have missed. Don’t let these fun credits slip away!

Questions:

1. Identify the leukocyte indicated with the arrow.
2. Which of the following is the best interpretation for the mild anemia in this case

1. Nonregenerative anemia
2. Regenerative anemia

3. Which of the following basic mechanisms of anemia is likely in this case based upon the microscopic findings?

1. Bone marrow failure
2. Early (within three days) blood loss
3. Late (after 3–5 days) blood loss
4. Hemolytic disease

Figure 1.	Peripheral blood film from a dog with a hematocrit of 31.1% from an in-house hematology analyzer, monolayer region of blood film, Wright’s stain, 100x objective field of view.

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*Each interactive challenge meets the requirements for 0.5 hour of continuing education credit in jurisdictions that recognize AAVSB’s RACE approval, however, participants should be aware that some boards have limitations on the number of hours accepted in certain categories and/or restrictions on certain methods of delivery of continuing education.

AAVSB Provider Number 106

^†Interactive challenges are also approved in Australia for 0.5 AVA Vet Ed Point and from the following Canadian Veterinary Medical Associations: Alberta, Saskatchewan, New Brunswick and Prince Edward Island.

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