Animal Health Diagnostic Center

Sign in | Register

ClinPath Banner  

Clinical Pathology


Automated Hemograms and Panels

The Advia hematology analyzer used in the Clinical Pathology Laboratory at Cornell University can perform an automated hemogram in dogs, cats, horses, cattle, sheep, goats, pigs, certain species of monkeys, rats and mice. We recommend this test primarily for research samples.

Automated hemogram

This provides the following parameters:

  • Total leukocyte count
  • Differential leukocyte count (absolute values):
    This includes neutrophils, lymphocytes, monocytes, eosinophils, basophils and large unstained cells (LUC). Large unstained cells are either large or reactive lymphocytes, monocytes or leukemic blasts. In most animals, they are large lymphocytes or monocytes.
  • Red cell parameters:
    RBC count, Hgb concentration, HCT, red cell indices (MCV, MCH, MCHC and RDW).
  • Platelet parameters:
    Platelet count and MPV. A platelet count will only be provided if the Advia provides a relatively accurate count. If the Advia detects platelet clumps, this will be flagged on the report.

A blood smear examination, plasma appearance and total protein (by refractometer) assessment is not performed with an auomated CBC. Furthermore, a reticulocyte count is not automatically added to samples from dogs (HCT < 39%) and cats (HCT < 25%). The total leukocyte count (and absolute differential cell counts) are not corrected for nucleated red blood cells, as these are not individually quantified by the analyzer. Therefore, the auomated hemogram does not provide the following information:

  • Assessment of red cell morphology
  • Assessment of white cell morphology:
    This includes details such as toxic change. The Advia cannot quantify a left shift (bands are included in the total neutrophil count).
  • Evaluation for erythroparasites or other infectious agents (e.g. Ehrlichia).

Automated WBC panel

This provides the following information:

  • Total leukocyte count
  • Differential leukocyte count (absolute values):
    This includes neutrophils, lymphocytes, monocytes, eosinophils, basophils and large unstained cells (LUC). Large unstained cells are either large or reactive lymphocytes, monocytes or leukemic blasts. In most animals, they are large lymphocytes or monocytes.

 

General Points Regarding Automated Hematology Tests

Correlations:

Studies in our laboratory in populations of both healthy and sick animals has shown that the automated differential cell count correlates well with manual (counting cells in a blood smear) neutrophil and lymphocyte counts in all species evaluated (dogs, cats, horses, cattle and goats). The correlation to eosinophils is species-dependent (good in dogs, healthy cats, cattle and goats; weaker in sick cats, horses). The correlation to monocytes is weak (all species evaluated) and poor for basophils (all species evaluated).

Accuracy:

In some samples, the automated differential count will be inaccurate. This usually occurs in old samples and samples with large numbers of platelet clumps. When this occurs, a comment will be appended to the automated differential cell count, indicating that it is inaccurate and recommending that a manual differential cell count be performed on the sample (this will need to be added on as an extra test for an additional charge). The automated hemogram is accurate for at least 24 hours in samples maintained at 4°C in dogs, cats, horses and cattle.

Abnormalities:

In some cases, abnormalities in the leukocytes may be apparent in certain samples in the data from the Advia. e.g. large numbers of nucleated red blood cells, the presence of a left shift. In these cases, we will flag the automated differential to highlight these abnormalities may be present. In such cases, we recommend that a blood smear examination be performed (which will include a manual differential cell count).