Inflammatory Biomarkers in Sickle Cell Disease: Understanding Their Role in Predicting the Disease-Related Complications

Sickle cell disease (SCD) is characterized by a chronic inflammatory state that leads to various complications. In this investigation, we quantified circulating levels of select inflammatory biomarkers including white blood cell count (WBC), C-reactive protein (CRP), and pro-inflammatory cytokines (Interleukin-1 (IL-1), Interleukin-6 (IL-6), Interleukin-8 (IL-8), and Tumor Necrosis Factor-α (TNF-α)) in a cohort of 66 patients with SCD during the steady-state. These were compared to levels in a control group, and we analyzed the association between changes in these biomarkers and the risk of SCD-related complications using odds ratios. Thus we found elevated levels of those inflammatory biomarkers when compared to controls. High WBC count was significantly more common in SCD patients with a history of recurrent infections and with cholelithiasis, but significantly less common in patients who presented with repetitive vaso-occlusive crisis (VOC). The odds of high CRP were significantly higher in the patients who presented with acute splenic sequestration (ASS), but significantly less common in those with cholelithiasis, heart murmur, osteonecrosis of femoral heads and nephropathy. High levels of IL1 were less common in patients with repetitive VOC and acute chest syndrome. High levels of IL8 were significantly more common in patients with recurrent infections and with heart murmur, but significantly less commun in patients with ASS. High TNFα levels were significantly most common in patients who developed cholelithiasis. Consequently, the assessment of inflammatory biomarker profiles during the steady-state phenotype may serve as a prognostic indicator for the development of SCD-related complications.