Understanding and targeting erythroid cell metabolism.

Rheological Characteristics of Elderly Individuals with Sickle Cell Disease Compared with an Adult Sickle Cell Population

The Potential of Stem Cells as an In Vitro Source of Red Blood Cells for Transfusion

See article on page 3102–3112, in this issue

Primary Care Provider Use and Depression Screening Among Transitioning Adolescents and Young Adults with Sickle Cell Disease

Is Resistance Futile?

Functional characterization of Sec14L4 in hudep-2 and mouse knockout models reveals its essential role in erythropoiesis.

Sickle cell disease mainly affects African Americans, and studies on racial differences in sickle cell disease outcomes are scanty. This study examined racial and ethnic differences in sickle cell disease prevalence, comorbidities, and outcomes. Using the National Inpatient Sample database from 2016 to 2018, we identified patients' records with a diagnosis of sickle cell disease using the International Classification of Diseases, Tenth Revision codes. The overall study population was further stratified by race into Blacks, Whites, and Hispanics. Using logistic regression, comorbidities and outcomes among sickle cell disease patients were compared between the three races/ethnicities. Of the 74 817 hospitalized for sickle cell disease, 69 889 (93.4%) were Blacks, 3603 (4.8%) were Hispanics, and 1325 (1.8%) were Whites. Compared to Whites, Blacks were more likely to have significantly higher odds of sickle cell crisis (odds ratio [OR]: 3.32; 95% confidence interval [CI]: 2.66-4.14) and blood transfusion (OR: 1.66; 95% CI: 1.37-2.02). There was no difference in mortality between Blacks and Whites. Compared to Hispanics, Blacks had significantly higher odds of sickle cell crisis (OR: 1.35; 95% CI: 1.19-1.53) and blindness (OR: 2.94; 95% CI: 1.22-7.11), lower odds of asplenia (OR: 0.57; 95% CI: 0.45-0.71) and gallstones (OR: 0.75; 95% CI: 0.58-0.95). However, Blacks had statistically significantly lower odds of mortality of 0.60 (95% CI: 0.38-0.93) than Hispanics. Prevalent sickle cell type, severity, complications, and comorbidities vary in different races. Physicians need to be aware of these differences to manage sickle cell patients efficiently. This study hopes to inform further research regarding the reasons for varying disease characteristics among racial groups and bridge a gap in tailored management protocols.

Pyruvate Kinase Thermostability Is Associated with Red Blood Cell Adhesion, Deformability and Oxygen Affinity in Patients with Sickle Cell Disease

Prevalence and Clinical Correlations of Cyanocobalamin Deficiency in Adults with Sickle Cell Disease: A Single Center Cross-Sectional Study

Potential Therapeutic Applications of Jak2 Inhibitors in Beta-Thalassemia and Sickle Cell Disease,

1. Kathryn Westphal, MD* 2. Respicius Bakalemwa, MD† 3. Elizabeth Groothuis, MD, MPH* 1. *Department of Pediatrics, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 2. †Department of Pediatrics, Bugando Medical Centre, Mwanza, Tanzania A 12-year-old boy with sickle cell disease (SCD) is admitted to a hospital in Mwanza, Tanzania, with acute onset of periorbital and scalp swelling. Associated symptoms include fever, headache, difficulty breathing, and back pain. Because resources in sub-Saharan Africa are limited, access to comprehensive care for patients with SCD is variable. The general principles of management focus on early diagnosis, parental education, prevention of infection with vaccinations and prophylactic medications, prompt treatment of infection and pain, the use of hydroxyurea for stroke prevention, and blood transfusions for life-threatening anemia. This patient has a known diagnosis of SCD but has infrequent pain episodes and no previous transfusions. He is not receiving hydroxyurea or prophylaxis against bacterial infections or malaria. He has no history of stroke and no known head trauma. On presentation he is afebrile and his heart rate is 120 beats/min, respiratory rate is 40 breaths/min, and blood pressure is 105/75 mm Hg. His oxygen saturation is 92% in room air. Physical examination is significant for pallor, periorbital edema, scalp edema, dyspnea without adventitious lung sounds, and splenomegaly with diffuse abdominal tenderness. His scalp edema is fluctuant and extends posteriorly from the periorbital region, encompassing the entire scalp. Swelling is most prominent in the frontal and parietal areas. The overlying skin is nonerythematous and nontender but is warm to the touch. His neurologic examination has no focal findings, although generally he appears tired. Initial laboratory results demonstrate a white blood cell count of 84,000/μL (84×109/L) with a lymphocytic predominance (57%), a hemoglobin level of …

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and sickle cell disease (SCD) cause hemolysis, often occurring in individuals of African descent. These disorders co-occur frequently, and possibly interact, altering clinical outcomes in SCD. However, epidemiological investigations of SCD with G6PD deficiency have produced variable results. This contribution reviews the available data about the interaction of G6PD deficiency and SCD. Overall, G6PD deficiency contributes few, if any, effects to laboratory values and clinical outcomes in SCD patients, but may impact transfusion efficacy. This observation is most likely because of the relatively increased G6PD activity in the young red blood cell (RBC) population seen in SCD patients with or without G6PD deficiency. In addition, G6PD deficiency possibly interacts with other genetic modifiers, such as α thalassemia, hemoglobin F levels and SCD haplotype. Although G6PD deficiency is relatively common, it does not appear to clinically impact patients with SCD. Nonetheless, it is important to evaluate G6PD status in patients with SCD to avoid the use of medications that may cause hemolysis. Future studies evaluating the clinical impact of transfusions from G6PD-deficient RBC donors would be of the greatest benefit to the current literature.

Placental Abnormalities in the Humanized Mouse Model of Sickle Cell Disease

Purpose: Sickle cell disease (SCD) is a hereditary and chronic life-threatening disorder, characterized by haemolytic anaemia. Increased 2,3-diphosphoglycerate (2,3-DPG) concentrations, along with decreased oxygen affinity of hemoglobin, may be related to the variability of clinical outcomes in SCD. Furthermore, genomic health data holds promise to improve the prediction of disease severity in SCD. Based on the integration of genomics, metabolomics and clinical data from 1000 SCD patients, to be included in 2022, GenoMED4all aims to develop Artificial Intelligence (AI) based deep learning algorithms to improve the prediction of disease severity and phenotype in SCD. This study aims to correlate non-quantitative metabolomics data obtained from dried blood spots (DBS), one of the inputs for GenoMED4all, to quantitative measurement of 2,3-DPG. Aiming to improve the potential of non-quantitative metabolomics from DBS to asses 2,3-DPG. Materials and methods: In snap frozen blood samples from 37 SCD patients and 29 healthy controls, 2,3-DPG was quantified by liquid chromatography mass spectrometry. 2,3-DPG was also detected in DBS from the same subjects by direct infusion high resolution mass spectrometry (DIHRMS). The oxygen tension at 50% Hb saturation (p50) was determined using a Hemox Analyzer (TCS). Statistical analysis were performed by Spearman’s correlation coefficients (SPSS v26.0.0.1) and Mann Whitney testing (GraphPad Prism v9.3.0). Results: After correcting for Hb, 2,3-DPG concentrations were higher in SCD patients than in controls (p<0.001) and Z-scores for 2,3-DPG, as assessed by DIHRMS, were similar in patients and controls. The Z-scores positively correlated with 2,3-DPG concentrations (Fig1A, 0.353, p=0.004). Because of the anaemia in SCD, red blood cells (RBCs) and plasma make up lower and higher volumes in the blood, respectively, compared to healthy controls. This affects the ratio of RBC and plasma metabolites on the DBS. DIHRMS detects a wide range of RBC and plasma metabolites, whereas the quantitative measurement is restricted to measuring 2,3-DPG of RBCs. To correct for those differences between methods, we applied a correction factor to the DIHRMS data using (1/Ht)*(1-Ht/1), correcting for the RBC volume (1/Ht) and the plasma volume (1-Ht/1). This resulted in a trend towards higher Z-scores in patients than controls (p=0.0597). Moreover, the positive correlation with 2,3-DPG concentrations increased to 0.526 (Fig1B, p<0.001). As 2,3-DPG affects the oxygen affinity of Hb, all measurements were correlated to p50. Expectedly, 2,3-DPG concentrations positively correlated with p50 (0.842, p<0.001). After applying the correction factor to the DIHRMS data, p50 correlations increased from 0.361 (p=0.003) to 0.529 (p<0.001). Conclusion: Strongest correlation between quantitative and non-quantitative methods for 2,3-DPG detection were observed after correcting for both RBC and plasma volumes in non-quantitative metabolomics. After correction, DIHRMS can be used to assess 2,3-DPG concentrations in DBS. This translation of non-quantitative to quantitative metabolomics for 2,3-DPG and potentially other RBC metabolites adds significant value to the use of DIHRMS, as DIHRMS is far more efficient in obtaining extensive information about the total metabolome than quantitative methods. The large population size and the AI based deep learning algorithms of GenoMED4all will enable to evaluate the potential of non-quantitative metabolomics in SCD. Funding: Horizon2020, GenoMED4all(https://genomed4all.eu/), Agios Pharmaceuticals Inc., ERN-EuroBloodNetFig 1. correlations between non-quantitative (Z-score) and quantitative 2,3-DPG detection A) non-quantitative and quantitative 2,3-DPG detection B) non-quantitative detection corrected for RBC and plasma volume and quantitative 2,3-DPG detection The authors do not declare any conflict of interest

Sickle cell disease affects more than 30 million people worldwide, including 0.1% of the population in Lebanon. It is characterized by unpredictable and painful vaso-occlusive crises (VOCs) that may lead to serious complications. This study describes the clinical burden of sickle cell disease in a cohort of patients treated at a comprehensive sickle cell disease referral center in Tripoli, Northern Lebanon. Patient demographics, clinical events, treatment, and survival were evaluated from a local, hospital-based registry of 334 sickle cell disease patients treated at the Nini Hospital, Tripoli, Lebanon, between 2009 and 2019. Mean age at sickle cell disease diagnosis and at first clinic visit was 2.9 and 8.5 years, respectively. Pain was the most common clinical event observed among all patients. Over the 10-year follow-up period, 15 (4.5%) patients died. Hydroxyurea (HU) and red blood cell (RBC) transfusions were the most commonly used therapies. One hundred and thirty-one (39.0%) patients were diagnosed with sickle cell disease at the Nini Hospital; the remaining patients were referred to and subsequently followed-up at the Nini Hospital. Eighty-seven (66.0%) Nini Hospital-diagnosed patients experienced a VOC. Seventy-four (85.0%) of these patients with a VOC event required HU during follow-up. Patients with a VOC required more RBC transfusions, cholecystectomy, and splenectomy than non-VOC patients. The high disease burden observed in this population of sickle cell disease patients illustrates a continued, unmet need to both prevent and manage VOC events and other sickle cell disease-associated complications.