scholarly journals Physiological properties and characteristic reactions of hydroxyurea

2020 ◽  
Vol 22 (100) ◽  
pp. 94-102
Author(s):  
O. G. Demchuk ◽  
M. R. Hrytsyna ◽  
L. O. Kobryn ◽  
M. B. Kalytovska ◽  
B. V. Gutyj
Keyword(s):  
Sickle Cell Disease ◽  
Life Expectancy ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Genetic Disorder ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Transfusion Therapy ◽  
Erythroid Precursors ◽  
Hb S

As it was mentioned in the previous paper, we observed the mechanism of action the interesting drug, first synthesized back in 1869 for the first time, called Hydroxyurea. A century later, phase I and II trials began to test its safety in humans with solid tumors. It was first approved by the FDA in 1967 for the treatment of neoplastic diseases and is presently approved for the treatment of melanoma, resistant chronic myelocytic leukemia (CML), and recurrent, metastatic testicular and ovarian cancer. Sickle cell disease is a genetic disorder that decreases life expectancy by 25 to 30 years. Individuals are diagnosed with sickle cell disease if they have one of several genotypes that result in at least half of their hemoglobin being hemoglobin S (HbS). Sickle cell anemia refers specifically to the condition associated with homozygosity for the Hb S mutation (Hb SS). Several other hemoglobin mutations, when occurring with an Hb S mutation, cause a similar but often milder disease than sickle cell anemia. In addition to reduced life expectancy, patients with sickle cell disease experience chronic pain and reduced quality of life. Painful crises, also known as vaso-occlusive crises, are the most common reason for emergency department use and hospitalization, and acute chest syndrome is the most common cause of death. Prior to the approval of hydroxyurea for use in sickle cell disease, patients with this condition were treated only with supportive therapies. These measures included penicillin in children to prevent pneumococcal disease, routine immunizations, and hydration and narcotic therapy to treat painful events. Red blood cell transfusions increase the blood’s oxygen carrying capacity and decrease the concentration of cells with abnormal hemoglobin, but chronic transfusion therapy predictably leads to iron overload and alloimmunization. Therapies such as hydroxyurea that raise fetal hemoglobin (Hb F, α2γ2) levels are promising because they effectively lower the concentration of Hb S within a cell, resulting in less polymerization of the abnormal hemoglobin.Hydroxyurea’s efficacy in sickle cell disease is generally attributed to its ability to raise the levels of Hb F in the blood; however, the mechanisms by which it does so are unclear. Early studies suggested that hydroxyurea is cytotoxic to the more rapidly dividing late erythroid precursors, resulting in the recruitment of early erythroid precursors with an increased capacity to produce HbF.

Clinical Complications in Adult Patients with Sickle Cell Anemia and β-Thalassemia-Sickle Cell Disease

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4767-4767
Author(s):  
Giovanna Graziadei ◽  
Alessia Marcon ◽  
Martina Soldarini ◽  
Ilaria Gandolfi ◽  
Luisa Ronzoni ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Acute Chest Syndrome ◽  
P Value ◽  
Cell Disease ◽  
Transfusion Therapy ◽  
Clinical Complications ◽  
Significant Difference ◽  
The Mean

Abstract Abstract 4767 Background. Sickle-Cell Disease (SCD) is one of the most common severe monogenic inherited disorders worldwide, due to hemoglobin S (HbS), with reduced affinity for the oxygen. HbS polymerization, leading to erythrocyte rigidity, vaso-occlusion and hemolytic anemia, is central in the pathophysiology and crucial for the clinical outcome. The term SCD refers to Sickle Cell Anemia (SCA) due to homozygosis for βS allele, HbS/β-thalassemia (T-SCD) due to compound of β-thal and βS allele, and HbSC disease, owing to the coinheritance of βS and βcalleles. SCD is a multiorgan disease characterized by recurrent acute events and progressive organ damage, worsening during the life. Aims. This is a retrospective monocentric study aimed to assess and compare the clinical complications among 59 adult SCD patients, followed at the Hereditary Anemia Centre of the Foundation IRCCS “Ca Granda” Ospedale Maggiore Policlinico, in Milan, Italy. Methods. Mutation analysis of the b globin gene was established by direct DNA sequencing on the ABI Prism 310 genetic analyzer. Clinical and hematological features were evaluated by routine tests and physical examination, with special attention to the erythropoiesis stress parameters as LDH values and extramedullary erythropoietic (EE) masses. Results. Fifty-nine adult SCD patients, 16 SCA and 43 T-SCD, were evaluated. In T-SCD patients detected b-mutations were severe (b°) in 69.8%, and moderate or mild (b+-b++) in 30.2%. The mean age of SCA patients was 36±9 and 41±11 years for T-SCD patients. For both groups the mean follow-up was 20±6 years, while the mean age at the presentation in our Centre was 32±8 years in SCA patients and 31±10 years in T-SCD ones. Five out of 16 (31.2%) SCA patients and 16/43 (37.2%) T-SCD patients were male. HbF mean levels were 6.9±5.1% and 10.1±7.2%, respectively in SCA and T-SCD group; surprisingly Hb mean levels were lower in SCA (9.3±1.3 g/dl) than in T-SCD (9.9±1.4 g/dl) patients. Comparing SCA and T-SCD, there was statistically significant difference in splenic features: splenectomy was performed in 2/16 (12.5%) SCA patients vs 21/43 (48.8%) T-SCD patients (p-value < 0.01). Splenomegaly was absent in SCA, while was detected in 11/22 (50%) T-SCD (p-value < 0.0001); all SCA patients had functional asplenia, not observed in T-SCD patients; splenic infarctions were absent in SCA patients and were detected in 7/22 (31.8%) T-SCD patients, of whom 5 had splenomegaly and 2 had normal spleen size (pvalue <0.001). On the other side, there was not statistically significant difference in the prevalence of stroke, acute chest syndrome (ACS), bone pain crisis, sepsis, leg ulcers and priapism. However, we observed some clinical differences, even if not statistically significant. Cholecistectomy was performed in 4/16 (25%) SCA patients vs 17/43 (39.5%) T-SCD patients, and gallstones were detected respectively in 5/12 (41.7%) and in 14/26 (53.8%) of SCA and T-SCD patients. Thrombotic events were absent in SCA patients, compared to 4/43 (9.3%) T-SCD patients. Furthermore, we detected EE in 3/16 (18.6%) SCA and in 3/43 (7%) T-SCD, all carrying b° thal mutations. We underlie that Hb levels and LDH values were higher in SCA than in T-SCD patients (823±295 vs 689±209 U/L). About the treatment, 14/16 (87.5%) SCA and 31/43 (72%) T-SCD underwent to top-up transfusion; 5/43 (11.6%) T-SCD were regularly transfused. Seven out of 16 (43.8%) SCA and 18/43 (41.8%) T-SCD patients were treated with Hydroxycarbamide (HU). Criteria for transfusion therapy were: painful crisis not responsive to HU, major clinical complications, such as stroke or ACS, extramedullary erythropoietic masses associated with high LDH levels and low Hb values. Conclusions. These data suggest that SCA and T-SCD patients have similar clinical course. Splenomegaly is present only in T-SCD patients, probably due to the increased amount of extravascular hemolysis. Surprisingly, SCA patients showed EE and lower Hb levels with higher LDH values compared to T-SCD ones. This could be related to the prevalence of intravascular hemolysis, that can lead to erythropoietic stress in SCA, even if tissues are better oxygenated in these patients because of biochemical characteristic of HbS in terms of decreased oxygen affinity. These observations could be important to evaluate transfusion and HU treatment. Disclosures: Cappellini: Novartis: Research Funding.

scholarly journals Hydroxyurea Treatment for Sickle Cell Disease

2002 ◽  
Vol 2 ◽  
pp. 1706-1728 ◽  
Author(s):  
Martin H. Steinberg
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Fetal Hemoglobin ◽  
Hemoglobin Concentration ◽  
Pharmacologic Therapy ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Globin Chains ◽  
Hydroxyurea Treatment ◽  
Erythroid Precursors

High fetal hemoglobin (HbF) levels inhibit the polymerization of sickle hemoglobin (HbS) and reduce the complications of sickle cell disease. Pharmacologic agents that can reverse the switch from γ- to β-chain synthesis — γ-globin chains characterize HbF, and sickle β-globin chains are present in HbS — or selectively increase the proportion of adult erythroid precursors that maintain the ability to produce HbF are therapeutically useful. Hydroxyurea promotes HbF production by perturbing the maturation of erythroid precursors. This treatment increases the total hemoglobin concentration, reduces the vaso-occlusive complications of pain and acute chest syndrome, and attenuates mortality in adults. It is a promising beginning for pharmacologic therapy of sickle cell disease. Still, its effects are inconsistent, trials in infants and children are ongoing, and its ultimate value — and peril — when started early in life are still unknown.

Sickle crisis in the critically ill

2016 ◽  
Author(s):  
Shilpa Jain ◽  
Mark T. Gladwin
Keyword(s):  
Sickle Cell Disease ◽  
Blood Cell ◽  
Sickle Cell ◽  
Red Blood Cell ◽  
Systemic Infection ◽  
Red Blood Cell Transfusion ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Ischaemia Reperfusion Injury ◽  
Transfusion Therapy

Sickle cell disease crises are precipitated by an acute occlusion of microvessels, which can lead to end organ ischaemia reperfusion injury and acute haemolysis. Acute fat emboli syndrome, acute lung injury (the acute chest syndrome), acute pulmonary hypertension, and cor pulmonale, haemorrhagic and occlusive stroke, and systemic infection represent the most common life-threatening complications observed in current ICU practice. General principles of management in all patients admitted to the critical care unit are hydration, antibiotics, pain control, and maintenance of oxygenation and ventilation. Red blood cell transfusion therapy is the treatment of choice for most complications of sickle cell disease requiring intensive care management. Transfusion of sickle negative, leukoreduced red blood cells, phenotypically matched for Rhesus and Kell antigens is the minimum standard of care in sickle cell disease patients as they have a high incidence of red blood cell alloimmunization.

scholarly journals Sickle Cell Disease: Management options and challenges in developing countries

2013 ◽  
Vol 5 (1) ◽  
pp. e2013062 ◽  
Author(s):  
Daniel Ansong ◽  
Alex Osei-Akoto ◽  
Delaena Ocloo ◽  
Kwaku Ohene-Frempong Ohene-Frempong
Keyword(s):  
Developing Countries ◽  
Sickle Cell Disease ◽  
Newborn Screening ◽  
Sickle Cell ◽  
Health Care Professionals ◽  
Genetic Disorder ◽  
Sub Saharan Africa ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Management Options

Sickle Cell Disease (SCD) is the most common genetic disorder of haemoglobin in sub-Saharan Africa. This commentary focuses on the management options available and the challenges that health care professionals in developing countries face in caring for patients with SCD. In developing countries like Ghana, newborn screening is now being implemented on a national scale.  Common and important morbidities associated with SCD are vaso-occlusive episodes, infections, Acute Chest Syndrome (ACS), Stroke and hip necrosis. Approaches to the management of these morbidities are far advanced in the developed countries. The differences in setting and resource limitations in developing countries bring challenges that have a major influence in management options in developing countries. Obviously clinicians in developing countries face challenges in managing SCD patients. However understanding the disease, its progression, and instituting the appropriate preventive methods are paramount in its management. Emphasis should be placed on newborn screening, anti-microbial prophylaxis, vaccination against infections, and training of healthcare workers, patients and caregivers. These interventions are affordable in developing countries.

An Evidence-Based Approach to the Treatment of Adults with Sickle Cell Disease

Hematology ◽  
2005 ◽  
Vol 2005 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Richard Lottenberg ◽  
Kathryn L. Hassell
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Enzyme Inhibitor ◽  
Controlled Trial ◽  
Acute Chest Syndrome ◽  
Evidence Based ◽  
Clinical Expertise ◽  
Cell Disease ◽  
Transfusion Therapy ◽  
Treatment And Prevention

Abstract The application of evidence-based medicine to the management of adults with sickle cell disease (SCD) is currently primarily driven by clinical expertise and patient preference, as there is a paucity of randomized controlled trial (RCT) data to guide decision-making. A summary of SCD management principles in the areas of health care maintenance, transfusion therapy, treatment and prevention of painful episodes, acute chest syndrome, stroke, renal disease, contraception and pregnancy, and priapism is predominantly based on the authors’ interpretation of available observational studies as well as the opinions of experts in SCD. RCTs impacting current practices address use of hydroxyurea to prevent painful episodes and acute chest syndrome, intensity of pre-operative transfusion, transfusion during pregnancy, and angiotensin-converting enzyme inhibitor therapy for proteinuria, but most issues in adult SCD care have not been rigorously studied and management may not be appropriately extrapolated from pediatric data. While challenging clinical problems need to be addressed by RCTs, there is also the need for development of practice guidelines using formal methodological strategies. This brief review is not a substitute for the process but provides a literature-based approach to making treatment decisions when caring for adults with SCD.

Severity of Sickle Cell Disease: Modeling Interrelationships among Hemolysis, Pulmonary Hypertension and Risk of Death.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 786-786
Author(s):  
Paola Sebastiani ◽  
Vikki G. Nolan ◽  
Clinton T. Baldwin ◽  
Maria M. Abad-Grau ◽  
Ling Wang ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Sickle Cell Disease ◽  
Disease Severity ◽  
Hemolytic Anemia ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Clinical Severity ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Risk Of Death

Abstract A single point mutation in the β hemoglobin gene causes sickle cell disease (SCD), but patients have extremely variable phenotypes. Hemolysis-related complications include pulmonary hypertension (PHT), priapism, stroke and leg ulceration; blood viscosity and sickle vasoocclusion are associated with painful episodes, acute chest syndrome and osteonecrosis. Predicting who is at highest risk of death would be useful therapeutically and prognostically. Applying Bayesian network modeling that describes complex interactions among many variables by factorizing their joint probability distribution into modules, to data from 3380 SCD patients, we constructed a disease severity score (DSS: 0, least severe; 1, most severe), defining severity as risk of death within 5 years. A network of 24 variables described complex associations among clinical and laboratory complications of SCD. The analysis was validated in 140 patients whose SCD severity was assessed by expert clinicians and 210 adults where severity was also assessed by the echocardiographic diagnosis of PHT and death. Information about PHT allowed a comparison of the DSS with the tricuspid regurgitant jet velocity (TRJV), an objective marker of PHT and an independent risk factor for death. DSS and three indices of clinical severity (severity ranking of individuals by expert clinicians; objective measurement of the presence and severity of PHT; risk of prospective death) were correlated. Among living subjects, the median score was 0.57 in 135 patients without PHT, 0.64 in 40 patients with mild PHT and 0.86 in 15 patients with severe PHT. The difference in average score between living patients with and without PHT is significant. The same increasing trend was noticeable in the subjects who died during follow-up: 0.60 in subjects without PHT; 0.68 in subjects with mild PHT; 0.79 in subjects with severe PHT. The utility of the DSS is also supported by the ability to assign a score to subjects for whom the TRJV cannot be measured. Surprisingly, besides known risk factors like renal insufficiency and leukocytosis, we identified the intensity of hemolytic anemia and clinical events associated with hemolytic anemia as contributing to risk for death. Priapism, an excellent reflection of the hemolytic anemia-related complications of SCD, is associated with PHT and its association with death was unexpected. Laboratory variables predictive of disease severity included LDH and reticulocytes that reflect the intensity of hemolytic anemia. Elevated systolic blood pressure increased the odds of death by 3.4, consistent with hypertension as a marker of early death in SCD. Subjects with sickle cell anemia are at greatest risk compared with subjects with sickle cell anemia-α thalassemia and with subjects with HbSC disease. Our model suggests that the intensity of hemolytic anemia, estimated by LDH, reticulocyte count and AST, and shown previously to be associated with PHT, priapism, leg ulceration and possibly stroke, is an important contributor to death. This model can be used to compute a personalized measure of disease severity that might be useful for guiding therapeutic decisions and designing clinical trials.

A Randomized Trial of the Safety and Benefit of Transfusion Vs. Standard Care In the Prevention of Sickle Cell-Related Complications In Adults: a Preliminary Report From the Phase II NHLBI Comprehensive Sickle Cell Centers (CSCC) Study of Neuropsychological Dysfunction and Neuroimaging Abnormalities In Neurologically Intact Adult Patients with Sickle Cell Disease

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3221-3221 ◽  
Author(s):  
Elliott Vichinsky ◽  
Lynne Neumayr ◽  
Jeffrey I Gold ◽  
Michael W Weiner ◽  
Jeffrey Kasten ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Adverse Events ◽  
Randomized Trial ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Preliminary Report ◽  
Standard Care ◽  
Neurocognitive Function ◽  
Cell Disease ◽  
Transfusion Therapy

Abstract Abstract 3221 Background: Most adult sickle cell anemia patients have received transfusion therapy. However, prospective studies evaluating the efficacy of transfusions in preventing sickle cell-related complications are lacking. The Phase II Neuropsychological Adult Sickle Cell Anemia Study is a randomized trial of chronic transfusion vs. standard of care in patients with abnormal neurocognitive function in order to determine the safety and benefits of transfusion therapy on neurocognitive function. A secondary goal of the study is to evaluate the benefit of chronic transfusion on the frequency and severity of acute sickle cell events; this is a preliminary report of this specific aim. Methods: Eligibility required normal neurological exam, WAIS III PIQ score ≤ 90, hemoglobin ≤ 9 g/dL, hemoglobin SS electrophoresis, and age between 21 and 55 years. Patients were randomly assigned to receive either standard care or transfusions. The transfusion goal was to maintain a hemoglobin of 2 g/dL rise over baseline with matched red cells for D, C/c, E/e, and Kell antigens. The protocol required simple transfusions at approximately 4 week intervals. Chelation therapy was not part of the study design. Patients underwent serial clinical and laboratory evaluations with central analysis of all clinical and transfusion events and complications. Laboratory testing of subjects in the transfusion arm included quantitative hemoglobin S/A, hemoglobin concentration, ferritin levels, and red cell antibody screening; a full hematology/chemistry panel was performed for all subjects at baseline, the study mid-point, and at the end of the study. Results: There were 20 patients in the transfusion arm (TX arm) with a mean age of 29 years vs. 16 patients in the standard care arm (SC arm) with a mean age of 30.5 years. The baseline data in the TX arm was similar to the SC arm: hemoglobin 7.8 vs. 8.0 g/dL; hematocrit 22.6% vs. 23.1%; hemoglobin F 10.5% vs. 12.5%. Thirty-five percent of patients randomized to the TX arm had a history of acute chest syndrome (ACS) vs. 31% in the SC arm; 30% of patients in the TX arm were on hydroxyurea compared to 50% in the SC arm. The TX arm patients have received an average of 5.6 transfusions (2 units per transfusion) with only one subject requiring an acute transfusion (5%); in contrast, 4 SC arm patients (25%) were transfused for acute events for a total of 7 units (average 1.8 per patient). The transfusion therapy improved the average hematologic status of patients: hemoglobin S% decreased from 85% to 32% (p=0.0003); hemoglobin and hematocrit increased from 7.6 to 9.4 g/dL (p=0.0052) and 22% to 28%, (p=0.007), respectively. Bilirubin declined from 3.6 to 2.4 mg/dL (p=0.042). In contrast, only bilirubin showed a significant decrease in the SC arm. In the TX arm, serum ferritin rose an average of 1318 to 2368 (p=.001); there was no change in liver function. There were no clinical transfusion reactions in the 120 study transfusions (360 units); however, one patient on routine screening reported a transient anti-D antibody without clinical or laboratory changes. Clinical Results: Adverse events were higher in the SC arm. Total number of adverse events in the TX arm were 23 (1.2 per person) vs. 66 in (4.1 per person) in the SC arm. There were 5 hospitalizations in the TX arm and 21 in the SC care arm, with a median number of hospitalized days per hospitalization of 5.0 and 6.0 respectively. The total number of serious events was 6 in the TX arm (0.3 per person) vs. 23 in the SC arm (1.4 per person). The total number of vaso-occlusive events in the TX arm were 14 (0.7 per person) vs. 57 (3.6 per person) in the SC arm. Acute pulmonary events occurred in 25% (4 patients) of the SC arm vs. none in the TX arm. Conclusions: This is preliminary data from the first prospective randomized study of the safety and efficacy of transfusion therapy in adults with SCD. We demonstrate the safety of transfusion therapy. Compared to standard therapy, transfusions improve or stabilize critical laboratory markers, decrease serious sickle cell anemia-related adverse events, and decrease in hospitalizations. Increase in ferritin is an expected outcome in transfused patients since chelation was not a part of this transfusion protocol. On completion of the study, the potential benefits of transfusion therapy on sickle cell disease morbidity including neurocognitive function will be reported. Disclosures: Field: Novartis Pharm: Honoraria.

scholarly journals Comparison between Automated Erythrocytopharesis (AECP) and Manual Exchange Transfusion (M-Ex)) in Reducing Hb-S and in Recovery of Acute Chest Syndrome and Other Acute Presentations of Sickle Cell Disease Patients

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4928-4928
Author(s):  
Said Yousuf Ahmed ◽  
Sameh M. Saleh ◽  
Mohamed Shefan Hameed ◽  
Ahmed M. Ragheb ◽  
Telal M. Abbas ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Sickle Cell Disease ◽  
Pulmonary Artery ◽  
Sickle Cell ◽  
Exchange Transfusion ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Hemoglobin S ◽  
Artery Thrombosis ◽  
Hb S

Abstract Background: Sickle Cell Disease represents a national health problem in Saudi Arabia with close to 150 thousands of the population are afflicted with the disease. Patients are frequently admitted with life threatening complications like Acute chest syndrome (ACS), Hyperhemolysis (HH), pneumonia, thromboembolism including pulmonary Artery Thrombosis (PAT) or severe protracted painful vasoocclusive crises (VOC). Rapid lowering of Hemoglobin S helps in reducing sickling and in alleviating such complications and allowing rapid recovery. Exchange transfusion is the fastest way to remove pathogenetic sickling red blood cells and reducing Hb S level to a safe level. It can be done manually (Mex) or via Automated Erythrocytopharesis machine (AECP). In this study we compared manual exchange to AECP in achieving the targeted lowering of Hb S and in accelerating clinical recovery. Patients and Methods: Patients included are sickle cell disease patients (HbSS, HbSC, Hb S/thal) admitted to the ER of a central Hospital. Indications of exchange were: acute chest syndrome, acute severe painful vaso-occlusive crises refractory to standard ER protocol of analgesia, stroke, priapism, Hyperhemolysis, and acute pulmonary embolism. P value of significance was calculated using student t-test comparing between median Hb S achieved after manual exchange vs AECP. To assess the rapidity of reversal of desaturation in acute chest syndrome patients, the cumulative incidence of reversal of desaturation and normalization of Oxygen saturation on room air were plotted against time at 0 time of the start of exchange, 2 hours,4 , 12, 24, 48 and 72 hours/discharge (D/C) Results: Table 1 shows clinic-biological characteristics of patients who underwent exchange transfusion. A total of 230 patients-admissions were registered between Dec 1. 2017 to July 27, 2018 for painful VOC to ER; 51 (32%) had clinical indications for exchange (ACS 25, Stroke / fits 1, priapism 1, pulmonary artery thrombosis 1, Hyperhemolysis with VOC (n:7) , VOC with HLH (n:1), and the remaining with "refractory" painful VOC with or without infection. One patient died immediately at the time of arrival to ER before starting any standard resuscitative measures . Exchange transfusion was indicated and done for 53 (23%); 12 (22,6%) AECP and the remaining (77.4%) had Manual Exchange. The median Hb S after manual exchange was 44 % (range 31-74%) which was unsatisfactory and way higher than the targeted level while Automated ECP reached down satisfactorily to a median of 31%(range 8%-50%) ; 67% of whom achieved it with only one session. No mortalities or major procedure related complication reported with manual or automated ECP. Procedurally, 3 patients needed 2 automated sessions and 1 patient used 2 kits for one session. Manual exchange could not achieve the target Hemoglobin S level below or around 30% due to logistic and technical difficulties and sometimes patients' refusal while Automated ECP reached to a mean Hb s level of 28%( range 8%-50%) and nearly two thirds (67%) reached to as low as 31% Hb S level with only one session of Automated ECP and was associated with rapid improvement of the oxygenation within the first 2 hours of the procedure. Conclusions: Erythrocytopharesis (Automated RBC exchange) is effective, quick and safe procedure that is life saving for many patients with ACS and is associated with less difficulties and complications if compared with the manual exchange. Because SCA is a national problem in Saudi Arabia and acute chest syndrome and other acute major complications comprehensively kill SCD patients, Automated Erythocytopharesis should be available nation-wide like dialysis machines at all large hospitals in all cities and should be distributed according to the prevalence of SCA in the area or location. Disclosures No relevant conflicts of interest to declare.

scholarly journals Regulatory Genetic Variation at the S100B Gene Associates with Vaso-Occlusive Manifestations in Sickle Cell Disease

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1063-1063 ◽  
Author(s):  
Xu Zhang ◽  
Wei Zhang ◽  
Santosh L. Saraf ◽  
Sergei Nekhai ◽  
Mark T Gladwin ◽  
...  
Keyword(s):  
Linkage Disequilibrium ◽  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Research Funding ◽  
Genetic Regulation ◽  
Acute Chest Syndrome ◽  
Cell Disease ◽  
Thrombotic Risk ◽  
Increased Risk

Abstract In sickle cell disease (SCD) polymerization of hemoglobin S under deoxygenated conditions causes vaso-occlusion, which can manifest as acute pain crisis and progressive bone/organ damage. Molecular studies have attributed vaso-occlusion to elevated vascular adhesion and inflammatory responses, whereas the genetic regulation has only recently been assessed. Genomic DNA isolated from peripheral blood mononuclear cells (PBMCs) was hybridized to Illumina Human 610-Quad SNP array for the PUSH and Walk-PHaSST cohorts and to Affrymetrix SNP 6.0 array for the Howard SCD expression cohort. Single nucleotide polymorphisms (SNPs) for 381 PUSH, 525 Walk-PHaSST, and 55 Howard patients were imputed to 1000 genomes project phase 3 data. Messenger RNA from PBMCs was profiled using Affymetrix Human Exon 1.0 ST Array for the Howard expression cohort and Affymetrix Human gene 2.0 ST array for the UIC expression cohort. Patients within the PUSH and Walk-PHaSST cohorts were classified to four groups according to a cumulative pain score, calculated based on pain frequency and questionnaire description of pain intensity. Pain grouping was examined for correlation with other SCD complications using Cochran Armitage test. History of acute chest syndrome (ACS, PUSH P=3.8×10-9, Walk-PHaSST P=2.4×10-5) and avascular necrosis (AVN, PUSH P=4.1×10-4, Walk-PHaSST P=3.7×10-5) were the most significant clinical manifestations that consistently associated with pain in the two cohorts. To investigate the genetic control of vaso-occlusive manifestations with appropriate power, we leveraged genetic association of pain, ACS, and AVN with genetic regulation of disease-specific gene expression. We mapped expression quantitative trait loci (eQTL) in the Howard expression cohort for SNPs<1 Mb away from gene ends per expression trait. At a permutation based false discovery rate of 5%, 1004 independent eQTL (linkage disequilibrium r2 ≤0.3 per trait) were identified for 880 genes. Focusing on 129 genes whose expression was altered in PBMCs in sickle cell anemia by at least 1.5-fold [1], we identified six eQTL for five differential genes (up-regulated: OSBP2, SLC14A1, RNF182, CCRL2; down-regulated: S100B). The six eQTL were assessed for association with pain, ACS, and AVN, using the Walk-PHaSST cohort for discovery and the PUSH cohort for validation. At a significance of Bonferroni corrected P=0.05 (nominal P=0.0083), an eQTL of S100B (rs2154586) significantly associated with AVN in the Walk-PHaSST cohort (OR=1.8, P=0.00061) and the association was replicated in the PUSH cohort (OR=2.7, P=0.0052). The A allele of the eQTL (frequency=0.18) associated with increased risk for AVN and increased expression level of S100B in the Howard expression cohort (β=0.40, P=1.6 ×10-6). In an additional 64 sickle cell anemia patients without hydroxyurea treatment from the UIC expression cohort, expression levels of S100B were significantly elevated in the individuals with AVN (β=0.28, P=0.029). The 24 SNPs in linkage disequilibrium with the eQTL (r2 >0.7) constituted the third most significant peak in a meta-analysis of genome-wide association of AVN in the PUSH and Walk-PHaSST cohorts. To test the hypothesis that genes involved in vaso-occlusion in SCD may affect thrombotic risk in non SCD individuals, we examined the association of the locus with venous thromboembolism (VTE) in the ARIC, JHS and CHS cohorts from dbGaP. The locus was imputed in African Americans and VTE was defined as being told by a doctor to have a blood clot in the leg or lung as answered in questionnaires during medical exams. The SNPs were associated with VTE using logistic linear regression adjusting for age, gender, enrollment site, and the first 15 principal components per cohort. The risk allele of the leading SNP for AVN consistently associated with increased risk of VTE across the cohorts, with a combined P=0.0041 and OR=1.4. S100B encodes a calcium sensor that appears to intervene in a variety of biological functions. S100B can mediate the inflammatory effects of damage-associated molecular pattern molecules (DAMPs) produced by erythrocyte hemolysis [2, 3]. Serum concentration of S100B correlates with LDH and with TCD-determined peak velocity of the left middle cerebral artery in thalassemia patients[4]. Polymorphisms of S100B that lead to increased serum levels are associated with increased risk of ischemic stroke in the Chinese population[5]. Disclosures Nekhai: NIMHD, NIH: Research Funding; NHLBI, NIH: Research Funding; NIAID, NIH: Research Funding.

Newborn Screening for Sickle Cell Disease: Effect on Mortality

PEDIATRICS ◽  
1989 ◽  
Vol 83 (5) ◽  
pp. 834-834
Author(s):  
Elliott Vichinsky ◽  
Deborah Hurst ◽  
Ann Earles ◽  
Klara Kleman ◽  
Bertram Lubin
Keyword(s):  
Sickle Cell Disease ◽  
Mortality Rate ◽  
Newborn Screening ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Comprehensive Treatment ◽  
Cell Disease ◽  
Screening Programs ◽  
Hb S ◽  
Overall Mortality

Newborn screening for sickle cell disease has been recommended as a method of decreasing patient mortality. However, its effectiveness in accomplishing this has not been reliably measured. To help determine the effectiveness, 10 years of experience in newborn screening have been summarized. The effects of early patient enrollment in a comprehensive treatment program on long-term morbidity and mortality are reported. From 1975 to 1985, 84,663 newborns were screened regardless of race or ethnic background. Hb Bait's was present in 5%, hemoglobin AS in 2.6%, and hemoglobin AC in 0.75%. Excluding Bart's, approximately 3.6% of all newborns were carriers for hemoglobinopathy. Sickle cell disease occurred in 1:951 births (58 Hb 55, 25 Hb FSC, three Hb S-β+-thalassemia, and three Hb S-β°-thalassemia). In addition, one in every 4,233 newborns had a clinically significant thalassemia syndrome (eight Hb FE, ten Hb F only, two Hb H). Compared with other newborn screening programs in California (congenital hypothyroidism, 1:3,849; phenylketonuria, 1:22,474; galactosemia, 1:74,103), hemoglobinopathies are the most prevalent congenital disease. Eighty-one newborns with sickle cell disease were followed up for 7.2 years. Patients experienced 513 hospitalizations, including 13 episodes of sepsis with or without meningitis and ten acute sequestration crises. The overall mortality rate for patients with sickle cell anemia diagnosed in the newborn period was 1.8%. In comparison, the clinical course of 64 patients with sickle cell anemia diagnosed after 3 months of age and followed up for an average of 9.4 years was analyzed. Five of these patients died. In two of these, sickle cell anemia was diagnosed at the time of the death. Overall mortality rate in this group was 8%. In summary, the data indicate that newborn screening, when coupled with extensive follow-up and education, will significantly decrease patient mortality.

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