This section provides information on the specific tests (how they are performed and how we interpret them) that are on a hemogram. Note that we have not included the estimation of total protein by refractometry or an assessment of plasma color, since this is not provided on all hemograms.
We have also provided the following helpful summaries:
- Quick test interpretation: A summary of interpreting increases and decreases in test results
- RBC method summary: How the different RBC results are generated by the analyzer used at Cornell University (ADVIA).
- RBC indices interpretation: How these indices can help us determine the cause of anemia.
Red blood cell tests
Various tests of red blood cells are performed on a hemogram. These include the following:
- Red blood cell number: Hematocrit (HCT), packed cell volume (PCV), red blood cell count, hemoglobin (Hgb) concentration
- Red blood cell indices: Mean cell volume (MCV), mean cell hemoglobin (MCH) or optical equivalent (CH), mean cell hemoglobin concentration (MCHC) or optically measured equivalent CHCM), red blood cell distribution width (RDW).
- Nucleated RBC: How nucleated RBC are identified and how they affect the WBC count.
- Reticulocyte counts: Reticulocyte percentage, absolute reticulocyte count that are used to assess regeneration in dogs and cats.
- Reticulocyte indices: Results obtained off optical- and flow-based analyzers, which can yield RBC indices for reticulocytes.
Other tests can also be performed on blood collected into EDTA for a hemogram.
- Coombs test: This test is mostly used as a diagnostic test for immune-mediated hemolytic anemia. We have provided information on this test which is used to detect the presence of immunoglobulins or complement attached on RBCs.
White blood cell tests
- Assessment of leukocyte numbers: Total WBC count (all cell types), relative (%) and absolute (cells/uL) differential leukocyte count (WBC separated by type).
- WBC morphologic features: These can give clues as to underlying disease pathogenesis or can identify the cause of the anemia, including parasites.
Platelet tests include the following:
- Platelet counts: This can be done via various methods and is part of most routine mammalian hemograms (unless the count is inaccurate).
- Manual counts: Using a hemocytometer
- Automated counts by hematologic analyzers, such as the one used by Cornell University.
- Blood smear estimation:
- See also tests for platelet number under Hemostasis.
- Mean platelet volume: This is only obtained by automated hematology analyzers and is provided on most routine mammalian hemograms.
- Other platelet tests: This includes plateletcrit (like the hematocrit), platelet component (cytoplasmic granularity or complexity), reticulated platelets, and platelet-associated IgG