Prevalence of Sickle Cell Anemia In Eastern India

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4822-4822
Author(s):  
Abhijit Chakraborty ◽  
Jayasri Basak ◽  
Deboshree Majumdar ◽  
Soma Mukhopadhyay ◽  
Sagnik Chakraborty ◽  
...  

Abstract Abstract 4822 Background: Sickle cell disease is an inherited disorder of hemoglobin synthesis. This is due to replacement of Valine for Glutamic Acid in position six of the Beta globin chain of hemoglobin. This genetic alteration yields unstable RBC which lasts for 10–20 days. In stressful conditions the cells become sickle shaped and get lysed. There are about 20 million people with sickle cell disease in India. During January 2009- May2010 camps were held in various parts of West Bengal, Jharkhand, Chattisgarh. Along with various mutations of thalassemia, we also observed sickle cell anemia among them. This triggered our interest to study the spectrum of the sickle mutation co-inheritant with different mutations such as Homozygous Sickle Cell, Sickle Cell-Beta0 Thalassemia, Sickle Cell-Beta+ Thalassemia, Severe β+ thalassemia genes, Moderate β+ thalassemia genes, Mild β+ thalassemia genes Sickle cell-HbE Thalassaemia, Sickle cell-HPFH Thalassaemia, in said part of India. Since Indian patients with SS disease had higher hemoglobin, red cell counts and higher HbF levels and lower HbA2, MCHC, MCV, and reticulocyte counts, hence a high hemoglobin is a risk factor for painful crises and may also be a risk factor for avascular necrosis of the femoral head, proliferative sickle retinopathy, and acute chest syndrome. Methods: We have screened 332 individuals in eastern part of India during the period January 2009- May 2010. 3ml of peripheral blood was collected in EDTA vial from each individual. NESTROFT (Naked Eye Single Tube Red Cell Osmotic Fragility Test) was performed on spot. Then Complete Blood Count was done within 24 hours of collection. HPLC (High Performance Liquid Chromatography) was performed to identify the samples for confirmation. In our observation in case of sickle cell anaemia HbF (Fetal haemoglobin), Hb (haemoglobin), MCV (mean corpuscular volume) values ranges between 0–10 %, ≤7-10g/dl, 65–90fl respectively. ARMS (Amplification Refractory Mutation System) PCR (polymerase chain reaction) was done to confirm the mutation. Result: Conclusion: Of the total samples collected in the camps held at various places of Jharkand, Chattisgarh & West Bengal 87 of them was carriers of sickle cell anemia. There was 7 homozygous (SS), 14 sickle beta, 12 double heterozygous for HPFH (High Persistance of Fetal Hemoglobin) & sickle cell anemia. In conclusion, the manifestations of sickle cell disease are influenced by a variety of other genetic and environmental factors. The occurrence of the disease against different genetic and environmental backgrounds provides experimental models that contribute to understanding the variability in clinical and hematological expression of the disease. Disclosures: No relevant conflicts of interest to declare.

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4691-4691
Author(s):  
Martin H. Steinberg ◽  
David H.K. Chui ◽  
George J. Dover ◽  
Paola Sebastiani ◽  
Abdulrahman Alsultan

HbF modulates the phenotype of sickle cell anemia by inhibiting deoxyHbS polymerization. HbF is confined to erythrocytes called F-cells that can be detected by FACS when these cells contain sufficient HbF. Measuring the amount of HbF/F-cell is difficult and not clinically available. African-Americans with sickle cell anemia have 2-80% F-cells with an average HbF/F-cell of 6.4±1.6 pg. The distribution of HbF/F-cell is highly individual regardless of HbF level. People with HbS-gene deletion hereditary persistence of HbF (HPFH) have a mean HbF of 30%, and HbF is evenly distributed among their erythrocytes. Polymer is not present in these cells either experimentally or after calculating the HbS polymer fraction at 70% O2 saturation. Therefore, each cell contains about 10 pg. of HbF. DeoxyHbS polymerization is prevented at physiologic venous and capillary O2 saturations of 40-70% when HbF/F-cell is 9-12 pgs. We call this the “protective” level of HbF. F-cells need not contain “protective” levels of HbF. Some β-globin gene cluster haplotypes are associated with high HbF. Carriers of these haplotypes can have milder disease. Nevertheless, even patients with high HbF can have frequent painful episodes, acute chest syndrome and osteonecrosis. Patients with HbS-δβ thalassemia have 15 to 25% HbF but are anemic and have vasoocclusive complications, albeit less often than in sickle cell anemia. Hydroxyurea reduces the morbidity and mortality of sickle cell anemia, an effect likely to be mediated by its induction of HbF. Patients treated with hydroxyurea are better and probably live longer, but adults are anemic and rarely asymptomatic. In all these patient groups, HbF is unevenly distributed among erythrocytes. In contrast, people with HbS-HPFH are nearly asymptomatic and not anemic. The failure of HbF to modulate uniformly all complications of sickle cell disease might be related to the heterogeneous concentration of HbF in sickle erythrocytes. HbF is associated with protection from the development of certain disease subphenotypes but has limited prognostic value in individuals. In many cross-sectional studies, high HbF was associated with a reduced rate of acute painful episodes, fewer leg ulcers, less osteonecrosis, less frequent acute chest syndromes and reduced disease severity. HbF had a weak or no clear association with priapism, urine albumin excretion, stroke and silent cerebral infarction, systemic blood pressure and tricuspid regurgitant velocity. Perhaps this is because intravascular hemolysis of cells with little or no HbF causes nitric oxide scavenging, or because these complications are less dependent on HbS polymerization. No study provides information on the concentration of HbF/F-cell other than providing the relatively meaningless calculated mean value. Rather than the total number of F-cells or the concentration of HbF in the hemolysate, HbF/F-cell and the proportion of F-cells that have “protective” HbF is the most critical predictor of the likelihood of some disease subphenotypes. Hypothetical distributions of HbF-cells with different levels of HbF/F-cell can be plotted for different concentrations of HbF. With mean HbF levels of 5%, 10% and 20%, and HbF content per cell of 1.5, 3 and 6 pg., assuming a fixed mean, the variance was changed to show how the distribution of HbF per cell can greatly vary, even if the mean is constant. For example, with 20% HbF, as few as 1% and as many as 24% of cells have “protective” HbF. When HbF is lower, few or no “protected” cells can be present. Due to the heterogeneous concentrations of HbF, HbS can polymerize in some F-cells that have sub-polymer inhibiting concentrations of HbF. Inducing high levels of HbF is one approach to treating sickle cell disease. Inactivating BCL11A, a repressor of γ-globin gene expression, abrogates sickle cell disease in transgenic sickle mice. Their HbF was distributed homogeneously, and their phenotype mimicked HbS-HPFH. If it becomes possible in humans to target BCL11A or its pathway with agents that affect gene transcription, will it result in pancellular HbF? Broadening the distribution of HbF amongst sickle erythrocytes with drugs like hydroxyurea that effect the kinetics of erythropoiesis, coupled with an agent whose primary mechanism of action is to increase the transcription of the γ-globin genes, might be the most fruitful approach to HbF induction therapy and more efficacious than single agent treatment. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 13-13
Author(s):  
Oladipo Cole ◽  
Asia Filatov ◽  
Javed Khanni ◽  
Patricio Espinosa

Moyamoya disease, well described in literature, is a chronic cerebrovascular occlusive disorder. It is characterized by progressive stenosis/occlusion of the terminal portions of the internal carotid arteries (ICA) and the proximal portions of the middle cerebral arteries (MCA). Less frequently described is Moyamoya syndrome, the name given to radiographic findings consistent with Moyamoya disease, but with an identifiable cause. The diseases associated with Moyamoya Syndrome include Sickle Cell Disease (SCD), Thalassemias, and Down's Syndrome to name a few. Common complications of Moyamoya include both ischemic and hemorrhagic strokes. Upon literature review, Moyamoya syndrome caused by SCD is not well described. When it is, the discussion is centered around the pediatric patient population and surgical management. Our case report describes a 22-year-old African American female with SCD who initially presented with Acute Chest Syndrome. Her hospital course was complicated by development of overt debilitating neurologic deficits. Subsequently, she was found to have Moyamoya Syndrome on neuroimaging. She was successfully treated with medical management without any surgical intervention. This case highlights the necessity of thorough examination, differential diagnosis, imaging findings, and consideration of predisposing syndromes in the work-up for Moyamoya syndrome; especially individuals with Sickle Cell Disease. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 10-11
Author(s):  
Satish Maharaj ◽  
Simone Chang ◽  
Karan Seegobin ◽  
Marwan Shaikh ◽  
Kamila I. Cisak

Background: Acute chest syndrome (ACS) frequently complicates sickle cell disease (SCD) and is a leading cause of hospitalization and mortality. Many factors have been implicated in ACS, including infections, thrombosis, fat and pulmonary emboli. However, a clear etiology is not defined in 50% of the cases and ACS is considered a clinical endpoint for different pathogenic processes (Vichinsky et al 2000). The non-specific nature of ACS makes diagnostic tests challenging, and there are no serum tests clinical used to aid diagnosis. Procalcitonin (PCT) is a prohormone of calcitonin and serum PCT rises within hours of an inflammatory stimulus. PCT has clinical utility as a marker of severe systemic inflammation, infection, and sepsis (Becker et al. 2008). Few studies have evaluated PCT as a biomarker for ACS in patients presenting with vaso-occlusive crises (VOC). Two studies have reported no difference in PCT (Biemond et al. 2018 and Stankovic et al 2011), while one study reported higher PCT between ACS and VOC (Patel et al 2014). Methods: We retrospectively reviewed 106 patients with SCD who presented to the emergency department with fever and painful crises during 2015-2019. The patients were divided into two categories based on discharge diagnoses - patients with VOC only (n=88) and patients with ACS (n=18). Inclusion criteria for both groups were patients with SCD, 17 years and older and PCT measurement on presentation. Exclusion criteria were defined as patients who had received empiric antibiotics prior to PCT testing. Data collected on presentation included genotype, age, gender, complete blood count, PCT, creatinine, total bilirubin and hydroxyurea use. Length of stay was recorded. Data was analyzed between the two groups using descriptive statistics and accounting for unequal variances, withp-value set at 0.05 for significance. Results: Demographics and clinical characteristics are summarized in Table 1 (Figure). The sample included primarily adult males (77%), with about two-thirds on hydroxyurea. Genotype HbSS (73.6%) was most prevalent followed by HbSC (22.6%) and HbSβ (3.8%). The ACS group had a higher percentage of HbSS, lower use of hydroxyurea and higher mean bilirubin. Mean PCT for the ACS group was 0.52 ng/mL (range, 0.05-2.04), compared to 0.31 ng/mL (range, 0.02-6.82) in the VOC group; withp=0.084. ROC analysis showed a PCT>0.5ng/mL had 39% sensitivity and 85% specificity for ACS in this sample. Conclusion: In this sample, PCT on presentation was higher in those with ACS compared to VOC, but this difference did not achieve statistical significance. Further study in a larger population would be useful to evaluate this finding. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 4 (2) ◽  
pp. 327-355 ◽  
Author(s):  
Stella T. Chou ◽  
Mouaz Alsawas ◽  
Ross M. Fasano ◽  
Joshua J. Field ◽  
Jeanne E. Hendrickson ◽  
...  

Background: Red cell transfusions remain a mainstay of therapy for patients with sickle cell disease (SCD), but pose significant clinical challenges. Guidance for specific indications and administration of transfusion, as well as screening, prevention, and management of alloimmunization, delayed hemolytic transfusion reactions (DHTRs), and iron overload may improve outcomes. Objective: Our objective was to develop evidence-based guidelines to support patients, clinicians, and other healthcare professionals in their decisions about transfusion support for SCD and the management of transfusion-related complications. Methods: The American Society of Hematology formed a multidisciplinary panel that was balanced to minimize bias from conflicts of interest and that included a patient representative. The panel prioritized clinical questions and outcomes. The Mayo Clinic Evidence-Based Practice Research Program supported the guideline development process. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to form recommendations, which were subject to public comment. Results: The panel developed 10 recommendations focused on red cell antigen typing and matching, indications, and mode of administration (simple vs red cell exchange), as well as screening, prevention, and management of alloimmunization, DHTRs, and iron overload. Conclusions: The majority of panel recommendations were conditional due to the paucity of direct, high-certainty evidence for outcomes of interest. Research priorities were identified, including prospective studies to understand the role of serologic vs genotypic red cell matching, the mechanism of HTRs resulting from specific alloantigens to inform therapy, the role and timing of regular transfusions during pregnancy for women, and the optimal treatment of transfusional iron overload in SCD.


2017 ◽  
Vol 9 (1) ◽  
pp. e2017013 ◽  
Author(s):  
Anil Pathare ◽  
Salam Alkindi

Background: Blood transfusion is an integral part of the supportive care for patients with sickle cell anemia and thalassaemia. The hazard of red cell alloimmunization, however, is one of the main complications of this therapy. Objectives: The aim of this study was to evaluate the incidence of red cell alloimmunization in Omani patients with sickle cell anemia and thalassaemia. Methods: This study included 262 patients whose historical transfusion records were available. One hundred and twenty-nine patients with thalassaemia who were attending the day care unit for regular transfusions, and 133 sickle cell anemia patients admitted at our hospital were included in this study. The Diamed gel system was used for the screening and identification of atypical antibodies. Results: The rate of alloimmunization in sickle cell anemia patients was 31% (n=41), whereas in thalassaemia patients it was 20% (n=26). Antibodies to E, e, C, c, D, K, S, Fyª, Kpª, Jkª and Cw were observed. Among the two groups, 8 developed nonspecific antibodies, and 12 developed more than one antibody; however, 85% of patients were also immunized to Rh and Kell antigens. Conclusions: Red cell transfusions are associated with a significant risk of alloimmunization. It is, therefore, imperative to perform an initial extended red cell phenotyping for both donors and recipients, and carefully select ABO, Rh and Kell matched donors.


Blood ◽  
2020 ◽  
Author(s):  
Solomon Ofori-Acquah ◽  
Rimi Hazra ◽  
Oluwaseun O Orikogbo ◽  
Danielle Crosby ◽  
Bethany Flage ◽  
...  

Acute kidney injury (AKI) is a major clinical concern in sickle cell disease (SCD). Clinical evidence suggests that red cell alarmins may cause AKI in SCD however the sterile inflammatory process involved has hitherto not been defined. We discovered that hemopexin deficiency in SCD is associated with a compensatory increase in alpha-1-microglobulin (A1M) resulting in up to 10-fold higher A1M/hemopexin ratio in SCD compared to health controls. The A1M/hemopexin ratio is associated with markers of hemolysis and AKI in both humans and mice with SCD. Studies in mice showed that excess heme is directed to the kidneys in SCD in a process involving A1M causing AKI while excess heme in controls is transported to the liver as expected. Using genetic and bone marrow chimeric tools, we confirmed that hemopexin deficiency promotes AKI in sickle mice under hemolytic stress. However, AKI was blocked when hemopexin deficiency in sickle mice was corrected with infusions of purified hemopexin prior to the induction of hemolytic stress. This study identifies acquired hemopexin deficiency as a risk factor of AKI in SCD and hemopexin replacement as a potential therapy.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 786-786
Author(s):  
Paola Sebastiani ◽  
Vikki G. Nolan ◽  
Clinton T. Baldwin ◽  
Maria M. Abad-Grau ◽  
Ling Wang ◽  
...  

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.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1540-1540 ◽  
Author(s):  
Latorya A Barber ◽  
Allison E Ashley-Koch ◽  
Melanie E. Garrett ◽  
Karen L Soldano ◽  
Marilyn J. Telen

Abstract Abstract 1540 Poster Board I-563 Tumor necrosis factor alpha (TNFα) is a pro-inflammatory cytokine that stimulates phagocytosis, neutrophil recruitment, and expression of adhesion molecule VCAM-1. Plasma levels of TNFα have been found to be increased in sickle cell disease (SCD), and in vitro studies show that TNFα causes increased adherence of sickle red blood cells to human umbilical vein endothelial cells. A polymorphism in the promoter region of the TNFα gene has previously been associated with stroke in children with SCD (Hoppe et al., 2007). The current study was designed to identify associations of additional TNFα single nucleotide polymorphisms (SNPs) with SCD clinical complications. We analyzed five SNPs in the TNFα gene in 509 DNA samples of SCD patients from Duke University, University of North Carolina at Chapel Hill, and Emory University. In our data set, cerebrovascular events (CVEs), including overt stroke, seizures, and transient ischemic attacks, occurred in 133 out of 509 SCD patients (26.1%). SNP genotyping was performed using Taqman genotyping assays from Applied Biosystems. Due to low minor allele frequencies (<0.05) for all the SNPs examined, genetic associations with SCD clinical complications were examined by using allele tests. After controlling for age, gender, and use of hydroxyurea, two of the five TNFα SNPs, rs2228088 and rs3093665, were significantly associated with CVEs (p=0.013 and 0.029, respectively). The odds that SCD patients with a G allele at rs2228088 suffered from CVEs were 0.485 times that for patients with the T allele, suggesting that the G allele had a protective effect. The odds of having the A allele at rs3093665 and suffering from CVEs was also reduced, at 0.45 compared to the C allele. Neither SNP was found to be in linkage disequilibrium (LD) with any of the other SNPs analyzed (r2≤0.002). There was also strong association of SNP rs2228088 with acute chest syndrome (ACS; p=0.003), occurring in 382 out of 509 SCD patients (75%). However, in this analysis, the G allele was associated with increased risk for ACS (OR=2.313). In addition to the association with CVEs, the SNP rs3093665 was also significantly associated with priapism (p=0.03), reported by 86 of 223 male SCD patients (38.6%). In this analysis, the A allele was protective, as had been observed for CVE (OR=0.188). Additionally, we found no difference in steady state plasma TNFα levels between genotypes for the two SNPs. The functional significance of these SNPs is presently unknown. SNP rs2228088 is a synonymous SNP located in the coding region, and rs3093665 is located in the 3' untranslated region of the TNFα gene. While the G to T change at SNP rs2228088 does not translate to a change in amino acid sequence, the A to C change at SNP rs3093665 may affect mRNA stability due to its location. It is also possible that one or both of these SNPs is in LD with another functionally relevant SNP. Our findings thus support previous data implicating TNFα polymorphisms in risk for central nervous system events. Interestingly, ACS has been previously associated with seizures, stroke and altered mental status in adults and children with SCD (Vinchinsky et al., 2000) and with silent cerebral infarcts and reversible posterior leukoencephalopathy syndrome in children with SCD (Henderson et al., 2003). However, in our dataset, ACS and the occurrence of CVEs were not associated (p=0.24). Further studies are required to elucidate these and other factors that potentially correlate with SCD clinical complications. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4767-4767
Author(s):  
Giovanna Graziadei ◽  
Alessia Marcon ◽  
Martina Soldarini ◽  
Ilaria Gandolfi ◽  
Luisa Ronzoni ◽  
...  

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.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2226-2226
Author(s):  
Anne M Marsh ◽  
Raymond Schiffelers ◽  
Ginny Gildengorin ◽  
Frans A Kuypers ◽  
Carolyn Hoppe

Abstract Introduction Sickle cell disease (SCD) is the most common cause of osteonecrosis of the femoral head (ONFH) in children. ONFH is a debilitating condition that is associated with mobility limitations, chronic pain, and an impaired quality of life. While the mechanisms that cause ONFH remain unknown, ischemia from recurrent microvascular occlusion is likely to play a role. Vascular occlusion may result directly from obstruction by sickled cells, or indirectly via complex interdependent pathways characterized by sustained endothelial activation, chronic inflammation, and coagulation. Microparticles (MP) are small, cell membrane-derived vesicles generated in response to cellular activation, injury or apoptosis. MPs have emerged as potential modulators of inflammation and thrombosis and have been found to be elevated in patients with ONFH in the general population. Objective This pilot study examined whether microparticle levels in patients with SCD who have ONFH differ from SCD patients without ONFH, as well as healthy African American (AA) controls. Methods Subjects were recruited at their baseline status and were excluded if they had been transfused within the past 30 days, hospitalized for a vaso-occlusive pain episode, acute chest syndrome, fever or surgery within the past 30 days, or had bony lesions of the femur or hip due to causes unrelated to SCD. For MP analysis, whole blood was collected in sodium citrate tubes and centrifuged for 15 minutes at 1500 x g at 20° C to generate platelet poor plasma. Aliquots of the plasma were immediately frozen and stored at -80° C until the time of MP analysis. 300 μl samples were diluted in PBS and centrifuged at 10000 x g for 1hr and the supernatant was centrifuged at 100,000 x g for 2 hr. The pellet was re-suspended in 1 mL of PBS and subjected to nanoparticle-tracking analysis to determine concentration and size. Additional laboratory biomarkers of inflammation and coagulation, including highly-sensitive C-reactive protein (hs-CRP), von Willebrand factor antigen (vWF Ag), tissue factor (TF), and D-dimer were analyzed for differences between groups. Analysis of variance was used to compare MP and biomarker levels between the three groups. The institutional review board at Children's Hospital & Research Center Oakland approved the study protocol and written informed consent was obtained from all participants. Results Characteristics of the 30 subjects enrolled are shown in Table I. Total microparticle levels in ONFH(+) patients were 2.3-fold higher than in ONFH(-) patients, and 2.5-fold higher than in AA controls (Figure 1). Mean MP levels for ONFH(+) patients, ONFH(-) patients, and AA controls were 4.55 x 1010, 1.99 x 1010, and 1.85 x 1010, respectively. Microparticle levels in ONFH(-) SCD patients did not differ from AA controls. There were no statistically significant differences in hsCRP, vWF Ag, TF, or D-dimer levels between the ONFH(-) and ONFH(+) groups. Conclusions The results of this study demonstrate significantly elevated MP levels in individuals with SCD who have ONFH. Additional studies are needed to better understand the mechanistic effects of MPs on the development of ONFH and to determine whether MP levels may be useful as a predictive biomarker for early disease detection. This publication was supported by NIH/NCRR UCSF-CTSI Grant Number UL1 RR024131. Disclosures: No relevant conflicts of interest to declare.


Sign in / Sign up

Export Citation Format

Share Document