The platelet count-to-total lymphocyte count ratio (PLR) is a measure of the ratio between the number of platelets and the number of lymphocytes in the blood. It is a simple and inexpensive marker that can be calculated from a complete blood count (CBC) test.

PLR has been studied as a potential marker of inflammation and immune system dysfunction in various medical conditions. A higher PLR may indicate an imbalance between platelets and lymphocytes, which can be a sign of systemic inflammation or immune activation.

In some studies, a higher PLR has been associated with worse outcomes in various medical conditions, including cancer, cardiovascular disease, and infectious diseases. However, PLR is not a specific marker for any particular condition, and its clinical significance may vary depending on the underlying cause of the imbalance between platelets and lymphocytes.

PLR is not a diagnostic test, and it should be interpreted in the context of other clinical and laboratory findings. Further testing and evaluation may be necessary to determine the underlying cause of any abnormalities in PLR levels.