Outcomes of Sickle Cell Disorders in COVID-19 Infection: An Institutional Experience

Introduction: With the emergence of the Coronavirus Disease 2019 (COVID-19) as a global pandemic came the concern that it would adversely affect individuals with comorbid conditions. In sickle cell disease (SCD), the apprehension was largely driven by concerns that the disease causes chronic inflammation, organ dysfunction and a prothrombotic state, especially during a vaso-occlusive crisis. Our assumption and hypothesis was that SCD pathology would be exacerbated by SARS CoV-2 infection leading to higher rates of acute chest syndrome (ACS), venous thromboembolism (VTE), more robust inflammatory responses requiring ICU care and increased death rates. Sickle cell trait (SCT) is frequently perceived as a benign condition; however, mounting evidence has shown that severe hypoxia (such as that seen in COVID-19 infection) can trigger sickle-related complication such as VTE, papillary necrosis and splenic infarcts and, in rare cases, ACS. In this retrospective analysis, we aimed to determine if sickle cell disorders (SCD & SCT) would confer poorer outcomes and/or increased mortality due to COVID-19 infection. Methods: Within the MedStar health care system there are 7,551 adult patients with a diagnosis of sickle cell disorder. We performed a retrospective chart review of all patients in the MedStar system with hemoglobinopathy and a lab-verified diagnosis of COVID-19 infection between March 1, 2020 and June 30, 2020. Sixty-one patients met our search criteria with 21 patients admitted to the hospital and 40 patients managed in the outpatient setting. Of the 21 patients admitted: 9 patients had sickle cell disease (Hb SS, Hb SC, Hb SB thalassemia) and 11 patients had sickle cell trait. One patient had HbC disease. Results: Results were analyzed by SCD genotype (Hb SS, Hb SC, Hb SB Thalassemia) versus the presence of a SCT. Due to the small sample size, statistical significance was not met in the variables. In the 21-patient cohort: 76.2% were female (60% of SCD and 90.9% of SCT) and 100% were African American. Median age was 46.5 years in the SCD group and 38 years in the SCT group. Length of stay was 10 days in the SCD group and 6 days in the SCT group. Mean peak white blood cell count and platelet count were significantly higher in SCD group (WBC: 15.1 k/uL vs 7.5 k/uL; p value 0.099. Platelets: 523 k/uL vs 185 k/uL; p value 0.082). Inflammatory markers were more elevated in the SCD cohort: mean Ferritin (915 ng/mL vs 520 ng/mL), mean D Dimer (2.96 mg/L vs 1.07