CD45-Percent

What is the CD45 percent test and why is it important?

CD45 is a protein expressed on the surface of most white blood cells, and the CD45 percent test measures the proportion of cells in a sample that express this marker. It is typically assessed using flow cytometry and serves as a general leukocyte marker. This test is crucial in evaluating immune function and differentiating between various types of white blood cells in both healthy and pathological states. In clinical settings, it is commonly used in hematologic evaluations and to aid in the diagnosis and monitoring of leukemias and lymphomas.


When is the CD45 percent test recommended?

Healthcare providers usually order the CD45 percent test when a patient presents with abnormal white blood cell counts or when there's suspicion of an immune system disorder, such as leukemia or lymphoma. It can also be part of routine immune profiling in patients undergoing immunotherapy or transplant evaluation. The test is often performed alongside other surface markers to distinguish between different white cell populations.


What do high or low CD45 percentages indicate?

A high CD45 percentage may suggest an overrepresentation of certain types of white blood cells, which could occur in some types of leukemias or reactive lymphocytosis. Conversely, a low percentage might be seen in conditions where non-leukocyte cells dominate, or in advanced immunosuppression, such as late-stage HIV or post-chemotherapy. Interpretation always depends on the clinical context and comparison with other immune markers.


How is the CD45 test performed?

This test is typically performed using flow cytometry, where a blood sample is stained with fluorescent antibodies specific to CD45 and analyzed for expression patterns. The results give a precise proportion of CD45-positive cells among total nucleated cells. It is a fast, reliable method and often part of a larger immunophenotyping panel.


Are there any precautions or preparations needed for this test?

There is no specific preparation needed before undergoing a CD45 percent test. However, it is important to inform your physician of any ongoing treatments, such as chemotherapy or immunosuppressive therapy, as these can influence the white cell count and CD45 expression.