This invention relates to the field of medical diagnostics and more specifically to systems and methods for enumerating immature platelets in a biological sample from a patient.
Reticulated platelets (RP) or immature platelets (IP) are young platelets that contain increased levels of mRNA and rRNA compared to mature cells. When thrombocytes are released from the bone marrow into the peripheral circulation they contain residual RNA which is subsequently degraded as the cells circulate. Concurrently, the size of the immature platelets becomes smaller as they mature. These young reticulated platelets appear normally in the peripheral blood at low levels, up to 4.5% of total thrombocytes.
An increased proportion or count of reticulated platelets may indicate increased thrombopoiesis. The ability to detect increased platelet production has proven to be useful clinically in patients with thrombocytopenia. If these patients have elevated levels of reticulated platelets it implies that they may have a disease or condition resulting in peripheral destruction of platelets. In contrast, if their levels of reticulated platelets are depressed, it implies that they may have a disease or condition which impairs the ability of the bone marrow to make new platelets.
The determination or counting of reticulated platelets is useful for the evaluation of thrombopoietic disorders like thrombocytopenia, for monitoring course and treatment of Idiopathic Thrombocytopenic Purpura (ITP), thrombotic thrombocytopenic purpura (TTP), and disseminated intravascular coagulation (DIC). Immature platelet event parameters, such as IP count or IP percentage of total platelets, can also be used as an early indicator of marrow recovery in patients post-chemotherapy and stem cell transplant.
Immature platelets were first described in 1969 by direct visualization from peripheral blood. Immature platelets can also be measured by flow cytometry. In some instances, however, IP measurement using flow cytometry methods can be expensive, time consuming, and may require considerable expertise. Further, IP measurement using flow cytometry methods may lack adequate quality control and standardization
Hence, although platelet analysis systems and methods are currently available and provide real benefits to patients in need thereof, many advances may still be made to provide improved devices and methods for assessing the status of platelets in an individual. Embodiments of the present invention provide solutions that address these problems, and hence provide answers to at least some of these outstanding needs.