The Relevance of Platelet Count and Platelet Lymphocyte Ratio in Sepsis - A Retrospective Study

BACKGROUND Beyond being the vital component in maintaining haemostasis, platelets play a vital role in inflammatory conditions and diseases. The aim of this study was to assess the association of platelet counts and platelet lymphocyte ratio (PLR) with severity of sepsis assessed using the Sequential Organ Failure Assessment (SOFA) Score. METHODS Authors did a retrospective study in 208 sepsis patients admitted in the MDICU. The platelet count and platelet lymphocyte ratio were calculated from the blood sample drawn within 24 hrs of admission. The study population was grouped based on platelet count (those with platelet count more than or equal to 1 lakh / cu mm and those with a count of less than 1 lakh / cu mm) and PLR (those with PLR of more than or equal to 200 and those with less than 200). The patients were also grouped based on the SOFA score of less than 10 and those with a score of more than or equal to 10. The association between these groups were then assessed. RESULTS 83 patients (65.4 %) who had SOFA score more than 10 had a platelet count > 1.5 lakh; whereas 29 patients (35.8 %) who had SOFA score more than 10 had a platelet count > 1.5 lakh. The number of patients who had both thrombocytopenia and a high SOFA score was only 29 (35.8 %). Similarly, the number of patients who had thrombocytopenia and low SOFA score was 52 (64.2 %). So, there was no correlation between high SOFA score (> 10) and thrombocytopenia at time of admission in our study. 45 patients (76.3 %) who had PLR more than 200 had a high SOFA score (> 10), whereas only 67 patients (45 %) with PLR less than 200 had SOFA score more than 10. This had a significant correlation with P value of 0.001. In group with SOFA score less than 10, 82 patients (55 %) had PLR less than 200, whereas in only 14 (23.7 %) had PLR > 200. Thus, in our study it was found that sepsis was more severe in patients who had a PLR of more than 200. CONCLUSIONS High platelet lymphocyte ratio calculated at the time of admission is associated with higher SOFA score. A PLR > 200 showed a significant association with patients with SOFA score > 10. This is a relatively economical and easily available parameter compared to the other biomarkers.