Platelet-Lymphocyte Ratio (PLR) Calculator

Platelet–Lymphocyte Ratio (PLR): Explanation and Clinical Context The Platelet–Lymphocyte Ratio (PLR) is a systemic inflammatory marker calculated as the ratio of platelet count to lymphocyte count in peripheral blood. Elevated PLR reflects both an increased platelet count, often associated with pro-thrombotic and inflammatory states, and a relative lymphopenia, indicating impaired immune regulation. PLR has been studied as a prognostic marker in cardiovascular diseases, including coronary artery disease, acute myocardial infarction, and heart failure, as well as in malignancies and other systemic inflammatory conditions.

Clinically, PLR can help stratify patients' risk, predict outcomes, and guide therapeutic decision-making in conjunction with other clinical and laboratory parameters. Reference ranges can vary; generally, a PLR between 100–300 is considered normal, while higher values may indicate worse prognosis.