"LaserCyte^® platelet information helped me diagnose immune-mediated thrombocytopenia in a male Bouvier patient recently. In-house platelet information is extremely valuable as we continue monitoring this patient. I can adjust his medications during the office visit."

Kathi Gruss, DVM
Earlysville Animal Hospital
Virginia

Our sincere thanks to Dr. Laura Baumert for providing us with this interesting case.

Canine Case Study
11-year-old, intact male beagle

Reason for Visit
Dropped off at the clinic by the owner because of a three-day history of not feeling or eating well, and vomiting. Body temperature was normal. The abdomen was painful on palpation with a possible anterior abdominal mass. Radiographs revealed hepatomegaly and a diffuse abdominal mass. Ultrasound examination confirmed hepatomegaly and identified several hypoechoic mid-abdominal masses that were suggestive of mesenteric lymph nodes. The CBC was performed as a component of a sick-patient panel, which included a chemistry profile.

Comments on LaserCyte® hematology report
Differential algorithm issues. Confirm with blood smear.

In addition to the "Differential algorithm issues" message, there are multiple quantitative abnormalities with this case. To help with the interpretation process, we'll analyze the hemogram as smaller components related to the red blood cell, white blood cell and platelet parameters.

11-year-old, intact male beagle: LaserCyte blood count
Test	Value	Units		Reference Range
WBC	18.69	K/µL	HIGH	5.50–16.90
LYMC	3.00	K/µL		0.70–6.00
MONO	2.73	K/µL	HIGH	0.10–1.40
NEU	12.24	K/µL	HIGH	3.00–12.00
EOS	0.62	K/µL		0.10–1.49
BASO	0.11	K/µL	HIGH	0.00–0.10
%LYM	16.00	%
%MONO	14.60	%
%NEU	65.50	%
%EOS	3.30	%
%BASO	0.60	%
HCT	52.50	%		37.00–55.00
RBC	7.80	M/µL		5.50–8.50
HGB	19.50	g/dL	HIGH	12.00–18.00
RETIC	38.90	K/µL
%RETIC	0.50	%
MCV	67.30	fL		60.00–77.00
RDW	15.50	%		14.70–17.90
MCHC	37.20	g/dL	HIGH	31.00–37.00
MCH	25.03	pg	HIGH	19.500–24.50
PLT	156	K/µL	LOW	175.00–500.00
MPV	29.38	fL
PCT	0.50	%
PDW	19.80	%
Differential algorithm issues. Confirm with blood smear.

Red Blood Cell Parameters—The red blood cell mass, based upon the evaluation of the hematocrit and red blood cell count, is a high-normal, indicating that no anemia is present. The hemoglobin is relatively high compared to the hematocrit. The hemoglobin typically is approximately one-third the hematocrit if there is normal hemoglobin distribution in the red blood cells. The increased MCH and MCHC are calculated values, which reflect this disproportionately high hemoglobin value. Hyperchromasia is suggested, however, this is physiologically impossible and suggests that there is some cell-free hemoglobin related to either in-vitro or in-vivo hemolysis that is being measured along with the intracellular hemoglobin. Marked lipemia, RBC autoagglutination and significant numbers of Heinz bodies can also cause increased MCHC values.

White Blood Cell Parameters—indicate mild leukocytosis characterized by a minimal neutrophilia, a mild monocytosis and a minimal basophilia. Neutrophil counts to this level may represent either a "normal" value for this particular animal (reference ranges represent approximately 95% of the normal population) or evidence of mild inflammation, or may be a physiologic neutrophilia associated with excitement (epinephrine effect). Monocyte counts of this degree are either related to inflammation, where there is a demand for macrophages in the tissues, or a glucocorticoid effect ("stress"); however, since the most common leukocyte abnormality typically seen in the dog associated with glucocorticoids, lymphopenia, is not present, the best interpretation of the mild monocytosis is inflammation. The basophilia is relatively minimal and of no obvious significance.

Platelet Parameters—indicate there is a mild thrombocytopenia with a suggestion of the presence of enlarged platelets with an increased mean platelet volume (MPV=29 fL, normally less than 15–20 fL) and platelets of varying sizes with an increased platelet distribution width (PDW=20%, normally less than 15%). Potentially these changes suggest bone marrow response to a peripheral demand for platelets, which would support an increased rate of peripheral consumption (coagulation) or destruction of platelets. With the slight thrombocytopenia, the bone marrow is not quite keeping up with the shortened circulating time of the platelets.

All of these interpretations are objectively made using solely the data generated from the LaserCyte Hematology Analyzer. Even when using the more advanced hematology analyzers like the LaserCyte and the instruments used in the reference laboratories, a blood smear examination is important to validate the numbers generated by the instrument. In this particular case, there was the added comment "Differential algorithm issues. Confirm with blood smear," which serves as a flag to the veterinarian that there could be something related to this specimen that is preventing the instrument from adequately evaluating this sample.

Blood Smear Scan—Within a few seconds of evaluating the feathered edge of the blood smear on this case, one is immediately struck with the finding of an atypical mononuclear cell associated with the other "normal" circulating leukocytes (Figure 1). These mononuclear cells are slightly larger than the neutrophil, and have relatively high nuclear/cytoplasmic ratios. There are many intracytoplasmic coarse purple granules preventing detailed evaluation of the nucleus.		Figure 1 click to enlarge
Morphology is most consistent with an atypical mast cell (Figure 2). With a low magnification field of view examination of the blood smear, it becomes quickly obvious that these cells represent greater than 50% of the total leukocyte population, making the differential provided by the instrument invalid.		Figure 2 click to enlarge
Note: The same sample was run on a reference laboratory instrument with very similar differential results and a flag to indicate that there was a potential problem with the automated differential, just as with the LaserCyte Hematology Analyzer.
In addition to recognizing this primary abnormality in the leukogram, examination of the red blood cells in the background reveals no additional significant findings, and the presence of enlarged and variably sized platelets is also confirmed (Figure 3).		Figure 3 click to enlarge

Several important points are identified in this case presentation:

1. Peripheral blood-smear evaluations are an important addition to the hemogram data generated by even the more advanced hematology analyzers. See the IDEXX Guide to Hematology in Dogs and Cats for more information on this topic, as well as additional pictures of mast cells.
2. When a flag is presented to the operator using the more advanced hematology analyzers, there is an even greater degree of need to validate results with a blood smear.
3. A quick scan of a peripheral blood smear should be performed to validate data from hematology analyzers that genererat a 5-part differential, such as the Advia®, Cell-Dyn® and the IDEXX LaserCyte Systems.

Case Disposition—In the clinic, the pet vomited a small amount of blood. The owner elected euthanasia, but did not give permission for a postmortem.

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 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.

Submit a case.

This summary was prepared by Drs. Dennis DeNicola and James Matthews of IDEXX Laboratories.

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IDEXX LaserCyte® interfaces with OmegaSoft

We are pleased to announce that our IDEXX LaserCyte Hematology Analyzer now interfaces with OmegaSoft. If you use OmegaSoft, this connectivity allows the flow of information from the LaserCyte analyzer into your patients' records, making a paperless practice possible and providing detailed diagnostics onscreen in minutes.

LaserCyte also interfaces with our own IDEXX Cornerstone® practice-management software and ImproMed Infinity and IntraVet® practice-information software.

For additional information, please contact:
IDEXX LaserCyte at 1-800-340-4579 or diagnosticedge@idexx.com
IDEXX Computer Services at 1-800-283-8386 or cornerstone@idexx.com

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Destin, Florida
Thursday, June 3
Georgia Veterinary Medical Association Meeting
Sandestin Golf and Beach Resort

The Most Frequently Misdiagnosed Disease in Veterinary Medicine
Fred Metzger, DVM, DABVP

Minneapolis, Minnesota
Thursday, June 10, 7:00–9:00 p.m.
American Collage of Veterinary Internal Medicine (ACVIM)
Minneapolis Convention Center

Special Interest Group: Association of Veterinary Hematology and Transfusion Medicine (AVHMT)
Jane Wardrop, DVM, MS, DACVP

Lubbock, Texas
Thursday, June 17, Registration at 6:30 p.m., Dinner and Talk at 7:00 p.m.
Holiday Inn Hotel and Towers

Practical Hematology
Dean Cornwell, MT (ACSP), DVM, PhD

RSVP to Evi Hill by June 11, 2004 at 1-800-551-0998, ext. 4227.

Worcester, Massachusetts
Tuesday, June 22, 2004, Registration and Dinner at 7:00 p.m., Talk at 7:45 p.m.
Crowne Plaza Hotel, Worcester

Blood-Smear Evaluation of the Dog and Cat
A. Rick Alleman, DVM, PhD, DABVP, DACVP

RSVP to Donnie Cotter by June 18, 2004 at 1-800-551-0998, ext. 8645.

East Rutherford, New Jersey
Wednesday, June 23, 2004, Registration and Dinner at 7:00 p.m., Talk at 7:45 p.m.
Sheraton Meadowlands Hotel and Conference Center

Blood-Smear Evaluation of the Dog and Cat
A. Rick Alleman, DVM, PhD, DABVP, DACVP

RSVP to Pam Goldenberg by June 18, 2004 at 1-800-551-0998, ext. 4275.

Providence, Rhode Island
Sunday, August 8, 2004, 1:00—3:00 p.m.
Northeast Veterinary Conference (NEVC)
Rhode Island Convention Center

Blood-Smear Evaluation: The Good, the Bad and the Ugly (Technician Training)
Allan Rebar, DVM, PhD

Providence, Rhode Island
Monday, August 8, 2004, 8:00 a.m.—4:30 p.m.
Northeast Veterinary Conference (NEVC)
Rhode Island Convention Center

Red and White Cell Responses in Disease/Case-Oriented Approach to Hemogram Interpretation
Allan Rebar, DVM, PhD

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Tips to Avoid Inadvertently Shutting Down the LaserCyte® Hematology Analyzer

The LaserCyte "shutdown" function is designed to turn off the LaserCyte analyzer for an extended period of time, such as when moving the veterinary clinic to a new location or during an extended remodeling period. Two occasions occur where users inadvertently shut down the LaserCyte analyzer.

• Moving Through the Screens Too Quickly
  The LaserCyte analyzer can be inadvertently shutdown by double-tapping a sequence of screens to speed up the process. In this situation, the second tap on the screen can be held over and may cause a button (e.g., the Shutdown button) on the following screen to be triggered.

• Restarting the Computer
  Restarting the LaserCyte computer on a weekly basis will help keep its performance optimal. Before doing this, make sure that no samples are being run on any of the instruments attached to the computer. To restart, tap the on/off button in the upper left corner of the main screen. A message asks if you are sure you want to shut down the computer. Tap Yes. The computer shuts down and the touchscreen turns off. Wait 10 seconds and then press the Optiplex power button on the front of the computer. The touchscreen turns on and, after a few minutes, the LaserCyte analyzer is ready to run samples again.

If you see the red Shutdown alert flashing on the screen, tap the Cancel button and continue with the task at hand. If you ever want to perform the shutdown or have any questions about it, contact the IDEXX LaserCyte Support Teams in the U.S. and Canada at 1-800-248-2483, or in Europe at 00-800-1234-3399.

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How does your LaserCyte® help you deliver better patient care?

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