Haematological Biomarkers for Distinguishing Vaso-Occlusive Crisis from Steady State in Patients with Sickle Cell Disease

Background and Objective: Vaso-occlusive crisis (VOC) is a major complication of sickle cell disease (SCD), characterized by increased haemolysis, inflammation, and thrombo-inflammatory activity. This study evaluated the diagnostic utility of routine haematological biomarkers for distinguishing patients with SCD during VOC from those in steady state. Materials and Methods: A comparative study was conducted among 180 participants aged 5-40 years in Bayelsa State, Nigeria, comprising 67 patients with SCD in crisis and 53 patients in steady state. Three millilitres of venous blood were collected into EDTA containers and analysed using a five-part haematology analyser. Haematological parameters, including Packed Cell Volume (PCV), White Blood Cell Count (WBC), differential leukocyte counts, Mean Cell Volume (MCV), Mean Cell Haemoglobin (MCH), Mean Cell Haemoglobin Concentration (MCHC), Platelet Count, Mean Platelet Volume (MPV), Absolute Neutrophil Count (ANC), and Neutrophil-to-Lymphocyte Ratio (NLR), were assessed. Data were analysed using SPSS version 27.0, with p<0.05 considered statistically significant. Results: Compared with steady-state patients, those in VOC had significantly lower PCV (21.56±4.54% vs 24.95±2.52%; p=0.007), higher WBC count (12.88±5.65 vs 7.74±2.07×10⁹/L; p = 0.001), neutrophil percentage (62.39±12.87% vs 54.45±5.83%; p=0.017), ANC (7.01±4.52 vs 2.35±0.74×10 /L; p<0.001), and NLR (2.72±1.52 vs 1.52±0.43; p=0.002). Other erythrocyte and platelet indices showed no statistically significant differences. Conclusion: Routine CBC-derived biomarkers, particularly PCV, WBC count, neutrophil percentage, ANC, and NLR, demonstrate potential utility for distinguishing VOC from steady state in SCD. Their accessibility and affordability make them valuable for disease monitoring and clinical decision-making in resource-limited settings.