Inflammatory and Coagulation Biomarkers in Sickle Cell Disease by Vaso-Occlusive Crisis and Pain Status: A Cross-Sectional Study

Background: Inflammation and coagulation activation contribute to sickle cell disease, but routine biomarkers have inconsistent associations with vaso-occlusive crisis and pain.Methods: This hospital-based cross-sectional analytical study included 54 patients with confirmed sickle cell disease.C-reactive protein, D-dimer, prothrombin time, and activated partial thromboplastin time were compared between the recorded vaso-occlusive crisis and steady-state groups.Serum 25-hydroxyvitamin D was compared between participants with and without pain or crisis at sampling.Two-sided Mann-Whitney U tests were used, with Holm correction across the five planned comparisons.Exploratory Kruskal-Wallis analyses assessed nine laboratory variables across three recorded clinical categories.Results: The dataset contained 17 steady-state participants, 23 with vaso-occlusive crisis, and 14 with chronic complications.D-dimer was higher during vaso-occlusive crisis than during steady state (median 1.62 vs. 0.96 micrograms of fibrinogen-equivalent units per milliliter; Holm-adjusted p=0.021; rank-biserial correlation=0.535).The 25-hydroxyvitamin D concentration was lower when pain or crisis was present (median 15.75 vs. 21.25 ng/mL; adjusted p=0.028; rank-biserial correlation=-0.436).C-reactive protein showed an unadjusted difference but did not remain significant after correction (adjusted p=0.083).Prothrombin time and activated partial thromboplastin time did not differ.Reticulocyte count showed the strongest exploratory difference across the three clinical categories (adjusted p<0.001).Conclusions: In this small cross-sectional cohort, D-dimer was higher in the vaso-occlusive crisis group, and 25-hydroxyvitamin D was lower among participants with pain or crisis at sampling after correction for five comparisons.The results do not establish diagnostic thresholds or causality.Larger prospective studies with clinically verified group assignment and adjustment for treatment and other confounders are required.