Platelet Count and Platelet Indices (Mean Platelet Volume, Platelet Distribution Width) and Red Cell Distribution Width and Their Significance in Severe Sepsis: A Hospital-Based Observational Study

Abstract

Background: Sepsis remains a leading cause of morbidity and mortality in intensive care settings worldwide. Early risk stratification is central to improving outcomes, but conventional biomarkers such as C-reactive protein (CRP) are limited by cost and delayed availability in resource-constrained settings. Platelet indices and red cell distribution width (RDW), both derived from a routine complete blood count, may serve as inexpensive surrogates of inflammation, coagulopathy and bone-marrow stress. Aim: To evaluate the association of platelet count, platelet indices (mean platelet volume [MPV], platelet distribution width [PDW], plateletcrit [PCT]) and RDW with disease severity (SOFA, qSOFA, APACHE II scores) and clinical outcome in patients with severe sepsis. Materials and Methods: This hospital-based observational study enrolled 90 adults with severe sepsis at a tertiary-care teaching hospital over two years. Platelet count, MPV, PDW, PCT, RDW and CRP were recorded at admission and serially at 24 and 72 hours, and correlated with SOFA, qSOFA and APACHE II scores and with clinical outcome (improvement, worsening or death). A p-value <0.05 was considered statistically significant. Results: Thrombocytopenia was present in 60.0% of patients at admission and was associated with poorer outcome. MPV and PDW correlated positively with SOFA, qSOFA and APACHE II scores (r = 0.34-0.51, p < 0.01) and with CRP (p < 0.05), while platelet count correlated negatively with CRP (p < 0.05). Patients with elevated MPV/PDW had a markedly lower rate of clinical improvement (68.8%) and a higher rate of death (14.5%) than those with normal indices (95.2% and 2.4%, respectively). RDW was elevated (>14.5%) in 57.8% of patients and was associated with a longer ICU stay and greater ventilator requirement, with a significant decline over 72 hours in patients who improved (p < 0.05). Conclusion: Platelet count, platelet indices and RDW - all obtainable from a single, inexpensive complete blood count - correlate closely with validated severity scores and clinical outcome in severe sepsis. Their combined interpretation, alongside CRP, offers a practical, low-cost tool for early risk stratification, particularly in resource-limited settings.