scholarly journals Validity of HbA1c in Diagnosing Diabetes Among People with Sickle Cell Trait in Tanzania

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4852-4852
Author(s):  
Belinda Kweka ◽  
Eric Lyimo ◽  
Jeremiah Kidola ◽  
Suzanne Filteau ◽  
Henrik Friis ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Sickle Cell ◽  
G6pd Deficiency ◽  
Conflicts Of Interest ◽  
Sickle Cell Trait ◽  
Categorical Variables ◽  
Oral Glucose ◽  
Diabetes Diagnosis ◽  
North Western ◽  
Western Tanzania

BACKGROUND: Hemoglobin A1c (HbA1c) measures the average of the past three month's glucose concentration and is recommended for diagnosing and monitoring diabetes. However in people with shorter red blood cells life spans like those with sickle cell trait (SCT), the test may underestimate the prevalence of diabetes. There are no data on the extent of this problem in East African region where the prevalence of SCT approaches 22%. OBJECTIVE: To compare diabetes diagnosis outcomes among adults with and without SCT by HbA1c and 2hrs oral glucose tolerance test (OGTT). METHODOLOGY: This was a cross sectional study conducted among patients who were previously recruited in the Chronic Infection, Cormobidities and Diabetes in Africa (CICADA) study, a cohort study investigating risk factors for diabetes in North western Tanzania during 2016 to 2021. Participants were included in this study if aged ≥18 years and were residents of Mwanza. After identification of eligible participants, stored blood samples were analyzed for SCT and other hemoglobinopathies i.e. thalassemia and G6PD deficiency through gene extraction, PCR and gel electrophoresis. Demographic, and anthropometric data as well as HbA1c and OGTT, hemoglobin, and lipids test results were available as part of CICADA study. Data were managed and analysed in stata. Student ttest was used for comparison of continuous variables while for categorical variables chi squire test was used. To investigate the validity of HbA1c, regression models were used to evaluate the association between SCT and diabetes diagnosis by HbA1c and OGTT separately. P< 0.05 indicated significant differences. RESULTS: 480 participants were included. Their mean age was 40.8 (±11.8) years, 292 (60.8%) were females, 128 (26.7%) had SCT and no sickle cell disease(SCD) which is homozygous trait observed. Those with SCT had lower body mass index (BMI) ((21.6(±4.3) vs. 22.5 (±5.0), P= 0.01) and lower HbA1c (5.2% vs. 5.9%, P<0.0001) compared to those without SCT. In multivariable logistic regression analysis adjusted for sex, age, BMI, another hemoglobinopathy which is thalassemia , G6PD deficiency , hemoglobin and lipids , participants with SCT were 88% less likely to be diagnosed with diabetes by HbA1c compared to those without SCT (OR=0.12, 95% CI (0.1,0.2), P <0.001). In contrast to logistic regression model adjusted for the same variables as above, SCT was not associated with diabetes diagnosis by OGTT (1.44, 95% CI (0.9, 2.3), P= 0.12). CONCLUSION: When compared with OGTT the findings shows that HbA1c systematically underestimate the prevalence of diabetes among people with SCT. The use of HbA1c for diabetes diagnosis should be done with caution especially in areas with high prevalence of SCT like in North Western Tanzania. Further research is needed to optimize the use of HbA1c in diagnosing and monitoring diabetes among people with SCT. Disclosures No relevant conflicts of interest to declare.

scholarly journals Influence of hemoglobinopathies and glucose-6-phosphate dehydrogenase deficiency on diagnosis of diabetes by HbA1c among Tanzanian adults with and without HIV: A cross-sectional study

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244782
Author(s):  
Belinda Kweka ◽  
Eric Lyimo ◽  
Kidola Jeremiah ◽  
Suzanne Filteau ◽  
Andrea M. Rehman ◽  
...  
Keyword(s):  
Sickle Cell ◽  
G6pd Deficiency ◽  
Sickle Cell Trait ◽  
Sub Saharan Africa ◽  
Oral Glucose ◽  
Chronic Infections ◽  
Cross Sectional ◽  
Adjusted Analysis ◽  
High Prevalence ◽  
Glucose 6 Phosphate Dehydrogenase

Introduction Hemoglobin A1c (HbA1c) is recommended for diagnosing and monitoring diabetes. However, in people with sickle cell disease (SCD), sickle cell trait (SCT), α-thalassemia or glucose-6-phosphate dehydrogenase (G6PD) deficiency, HbA1c may underestimate the prevalence of diabetes. There are no data on the extent of this problem in sub-Saharan Africa despite having high prevalence of these red blood cell disorders. Methods Blood samples from 431 adults in northwestern Tanzania, randomly selected from the prospective cohort study, Chronic Infections, Comorbidities and Diabetes in Africa (CICADA), were analysed for SCT/SCD, α-thalassemia and G6PD deficiency and tested for associations with the combined prevalence of prediabetes and diabetes (PD/DM) by HbA1c, using the HemoCue 501 HbA1c instrument, and by 2-hour oral glucose tolerance test (OGTT). Results The mean age of the participants was 40.5 (SD11.6) years; 61% were females and 71% were HIV-infected. Among 431 participants, 110 (25.5%) had SCT and none had SCD. Heterozygous α-thalassemia (heterozygous α+ AT) was present in 186 (43%) of the participants, while 52 participants (12%) had homozygous α-thalassemia (homozygous α+ AT). Furthermore, 40 (9.3%) participants, all females, had heterozygous G6PD deficiency while 24 (5.6%) males and 4 (0.9%) females had hemizygous and homozygous G6PD deficiency, respectively. In adjusted analysis, participants with SCT were 85% less likely to be diagnosed with PD/DM by HbA1c compared to those without SCT (OR = 0.15, 95% CI: 0.08, 0.26, P < 0.001). When using OGTT, in adjusted analysis, SCT was not associated with diagnosis of PD/DM while participants with homozygous α+ AT and hemizygous G6PD deficiency were more likely to be diagnosed with PD/DM. Conclusions HbA1c underestimates the prevalence of PD/DM among Tanzanian adults with SCT. Further research using other HbA1c instruments is needed to optimize HbA1c use among populations with high prevalence of hemoglobinopathies or G6PD deficiency.

scholarly journals Glucose 6 phosphate dehydrogenase deficiency and hemoglobinopathy in South Western Region Nepal: a boon or burden

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Narayan Gautam ◽  
Bhagwati Gaire ◽  
Trishna Manandhar ◽  
Bishnu P. Marasini ◽  
Niranjan Parajuli ◽  
...  
Keyword(s):  
Sickle Cell ◽  
G6pd Deficiency ◽  
Sickle Cell Trait ◽  
Amplification Refractory Mutation System ◽  
Cellulose Acetate Electrophoresis ◽  
Positive Trait ◽  
Arms Pcr ◽  
Phenotypic Method ◽  
Mutation System ◽  
Glucose 6 Phosphate Dehydrogenase

Abstract Objectives The study was carried out to optimize the phenotypic method to characterize the sickle cell trait (SCT), sickle cell anemia (SCA), and β-thalassemia (β-TT) suspected sample from tharu community of South Western province-5, Nepal. SCT and SCA were further evaluated by genotypic method employing amplification refractory mutation system (ARMS PCR). Moreover, Glucose 6 phosphate dehydrogenase (G6PD) was estimated in those hemoglobinopathy to observe its prevalence. The accurate and reliable method can play an important role in reduction of morbidity and mortality rate. Results The 100 suspected cases were subjected to phenotypic method adopting cellulose acetate electrophoresis and genotypic method using ARMS PCR which portraits (5%) SCA positive test showing HBS/HBS, (38%) SCT positive trait HBA/HBS and (36%) cases normal HBA/HBA. β-TT (21%) cases were confirmed by electropherogram. G6PD deficiency was observed in (40%) of SCA, (18.4%) of SCT, (4.8%) of β-TT and (2.8%) in normal cases. Increased G6PD were developed only in SCT (5.3%) and β-TT (4.8%). The study highlighted sickle cell disorder (SCD) and β-TT as the most common hemoglobinopathy coexisting with G6PD deficiency. Though hemoglobinopathy sometime could be protective in malaria but G6PD deficiency can cause massive hemolysis which may exacerbate the condition.

scholarly journals Risk of Venous Thrombosis in Patients with Sickle Cell Trait after Orthopedic Surgery

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 417-417
Author(s):  
Jahnavi Gollamudi ◽  
Sadeer Al-Kindi ◽  
Petra Martin ◽  
Jane Little ◽  
Lalitha V. Nayak
Keyword(s):  
Logistic Regression ◽  
Sickle Cell ◽  
Orthopedic Surgery ◽  
Research Funding ◽  
Sickle Cell Trait ◽  
Knee Surgery ◽  
Orthopedic Procedures ◽  
Major Orthopedic Surgery ◽  
The Us ◽  
Hip And Knee Surgery

Abstract Introduction Sickle cell trait (SCT) is considered to confer a hypercoagulable state. Historically, venous thromboembolism (VTE, deep vein thrombosis and PE) rates for untreated patients after major orthopedic surgery (hip or knee replacement or hip fracture surgery) have been close to 4.3%, however with the introduction of post-op anticoagulation, the rates have been as low as 1.15%. Although guidelines exist regarding anticoagulation for up to 35 days after major orthopedic surgery, there are no specific recommendations for patients with SCT. The purpose of this retrospective study is to examine the rates of VTE after major orthopedic surgery in a cohort of patients with SCT. We hypothesize that rates of VTE would be higher in patients with SCT and the risk of VTE would persist beyond 35 days. Methods A commercial database (Explorys Inc, Cleveland, OH, USA), an aggregate of electronic health record data from 26 major integrated US healthcare systems representing a sixth of the US population, was queried for data, using Systematized Nomenclature of Medicine (SNOMED) clinical terms or codes. Cases were defined as patients with SCT who underwent major knee or hip surgery. Since a majority of the US population with SCT are African American (AA) patients, controls were defined as AA patients without SCT undergoing major orthopedic surgery. For the primary end point of VTE, only adult patients (≥18 years) were selected. Those with previous history of VTE, thrombophilia, malignant disease, antiphospholipid antibody syndrome and other hemoglobinopathies such as sickle cell disease were excluded. 30 and 90-day rates of VTE were recorded for both groups. Logistic regression models were used to adjust of confounding variables (defined a priori as age > 65 or< 65, smoking, gender and presence or absence of body mass index > 30). Of note, SCT is likely under-estimated due to incomplete diagnosis. Rates or proportions were compared using Chi-squared testusing Medcalc software (2018). Logistic regression analysis was done using Statistical Package for Social Sciences (SPSS, version 21, IBM Corp, Armonk, NY). P< 0.05 was considered statistically significant. Results A total of 1360 major orthopedic surgeries in patients with SCT and 74040 surgeries in non-SCT patients were identified. 30 and 90-day VTE for SCT patients undergoing major orthopedic surgery was 9.7% each. 30 and 90 day VTE for non-SCT patients undergoing major hip and knee surgery were 5.9 % and 6.4 % respectively. The difference in 30-day and 90-day VTE rates between the SCT and non-SCT group was statistically significant (30 day VTE difference 3.1%, 95% CI 1.6650-4.7569, p < 0.001; 90 day VTE difference=3.6%; 95% CI 2.1658-5.2562, p= <0.001). The rates of anticoagulant dispensation (oral Xa inhibitors, enoxaparin or warfarin) after surgery were 56% and 46% in SCT and non-SCT group respectively (difference = 10%, 95% CI 7.32-12.64, p <0.001). Despite the higher proportion of patients prescribed for anticoagulants in the SCT population, there was still a higher 30 and 90-day VTE rate in that group. Compliance to anticoagulation and mortality from VTE could not be assessed in this study. Logistic regression of risk factors associated with risk of VTE revealed age over 65 years of age, female gender, active smoking status, obesity (BMI >30), and presence of sickle cell trait were all significantly associated with increased risk of both 30 and 90 day VTE post major orthopedic surgery. Please see Table 1 and 2 for further details. Conclusion Our study represents real life data outside of a clinical trial. We found that patients with SCT who underwent major hip and knee surgery had an increased 30 and 90-day VTE rates compared to non-SCT patients undergoing the same procedures. Overall, this cohort of AA patients had VTE rates higher than that were described in literature. Of note, AA patients overall are at a higher risk of VTE than are their Caucasian counterparts. The results from the study seem to suggest a role for extended prophylaxis in people with SCT who are undergoing orthopedic procedures, and warrants further study. Disclosures Little: Doris Duke Charitable Foundations: Research Funding; NHLBI: Research Funding; PCORI: Research Funding; Hemex: Patents & Royalties: Patent, no honoraria.

scholarly journals Student screening for inherited blood disorders in Bahrain

2021 ◽  
Vol 9 (3) ◽  
pp. 344-352
Author(s):  
S. Al Arrayed ◽  
N. Hafadh ◽  
S. Amin ◽  
H. Al Mukhareq ◽  
H. Sanad
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
G6pd Deficiency ◽  
High Performance ◽  
Sickle Cell Trait ◽  
Disease Incidence ◽  
Cell Disease ◽  
Blood Disorders ◽  
Inherited Disorders ◽  
Beta Thalassaemia

In Bahrain and neighbouring countries inherited disorders of haemoglobin, i. e. sickle-cell disease, thalassaemias and glucose-6-phosphate dehydrogenase [G6PD] deficiency, are common. As part of the National Student Screening Project to determine the prevalence of genetic blood disorders and raise awareness among young Bahrainis, we screened 11th-grade students from 38 schools [5685 students], organized lectures and distributed information about these disorders. Haemoglobin electrophoresis, high performance liquid chromatography, blood grouping and G6PD deficiency testing were performed. Prevalences were: 1.2% sickle-cell disease; 13.8% sickle-cell trait; 0.09% beta-thalassaemia; 2.9% beta-thalassaemia trait; 23.2% G6PD deficiency; 1.9% G6PD deficiency carrier. Health education, carrier screening and premarital counselling remain the best ways to reduce disease incidence with potentially significant financial savings and social and health benefits

scholarly journals Glucose-6-Phosphate Dehydrogenase (G6pd) Deficiency and Sickle Cell Trait among Blood Donors in Nigeria

2014 ◽  
Vol 2 (2) ◽  
pp. 51-55 ◽  
Author(s):  
Omisakin C.T ◽  
Esan A.J ◽  
Ogunleye A.A ◽  
O. Ojo-Bola ◽  
Owoseni M.F ◽  
...  
Keyword(s):  
Sickle Cell ◽  
G6pd Deficiency ◽  
Blood Donors ◽  
Sickle Cell Trait ◽  
Glucose 6 Phosphate Dehydrogenase

scholarly journals Glucose 6 Phosphate Dehydrogenase Deficiency and Hemoglobinopathy in South Western Region Nepal: A Boon or Burden

2019 ◽  
Author(s):  
Narayan Gautam ◽  
Bhagwati Gaire ◽  
Trishna Manandhar ◽  
Bishnu P Marasini ◽  
Niranjan Parajuli ◽  
...  
Keyword(s):  
Sickle Cell ◽  
G6pd Deficiency ◽  
Sickle Cell Trait ◽  
Amplification Refractory Mutation System ◽  
Cellulose Acetate Electrophoresis ◽  
Positive Trait ◽  
Arms Pcr ◽  
Phenotypic Method ◽  
Mutation System ◽  
Glucose 6 Phosphate Dehydrogenase

Abstract Objectives: The study was carried out to optimize the phenotypic method to characterize the sickle cell trait (SCT), sickle cell anaemia (SCA) and β-thalassemia (β-TT) suspected sample from tharu community of South Western province-5, Nepal. SCT and SCA were further evaluated by genotypic method employing amplification refractory mutation system (ARMS PCR). Moreover, Glucose 6 Phosphate Dehydrogenase (G6PD) was estimated in those hemoglobinopathy to observe its prevalence. The accurate and reliable method can play an important role in reduction of morbidity and mortality rate. Results: The 100 suspected cases were subjected to phenotypic method adopting cellulose acetate electrophoresis and genotypic metod using ARMS PCR which portraits (5%) SCA positive test showing HBS/HBS, (38%) SCT positive trait HBA/HBS and (36%) cases normal HBA/HBA. β-TT (21%) cases were confirmed by electropherogram. G6PD deficiency was observed in (40%) of SCA, (18.4%) of SCT, (4.8%) of β-TT and (2.8%) in normal cases. Increased G6PD were developed only in SCT (5.3 %) and β-TT (4.8%). The study highlighted sickle cell disorder (SCD) and β-TT as the most common hemoglobinopathy coexisting with G6PD deficiency. Though hemoglobinopathy sometime could be protective in malaria but G6PD deficiency can cause massive hemolysis which may exacerbate the condition.

Fetal Hemoglobin Promotes P. Falciparum Growth in Sickle Cell Disease Erythrocytes

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2252-2252
Author(s):  
Natasha M. Archer ◽  
Manoj Duraisingh
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Conflicts Of Interest ◽  
Sickle Cell Trait ◽  
Fetal Hemoglobin ◽  
Morbidity And Mortality ◽  
Multiplication Rate ◽  
Cell Disease ◽  
Low Oxygen ◽  
Parasite Multiplication

Introduction: We have demonstrated that sickle hemoglobin (HbS) polymerization in low oxygen (O2) is the main driver of sickle cell trait (AS) resistance to P.falciparum malaria. This suggests that homozygous sickle cell disease (SS) individuals should have even greater resistance to malaria. Instead SS individuals infected by P. falciparum often have increased malaria morbidity and mortality compared to individuals with normal hemoglobin (AA) or AS. The reasons for this paradox are poorly understood. We propose that fetal hemoglobin (HbF) inhibits polymerization thereby allowing parasite proliferation. To test this hypothesis the following experiments were performed. Methods: AA and SS erythrocytes were collected within two weeks of the assay date. P. falciparum 3D7 parasites were used for growth assays. Growth assays were performed at 1, 3, 5, 7.5, 10 and 16% O2 using synchronized schizonts obtained by magnet purification via the MACS system. Staging was performed via light microscopy analysis of May-Grünwald-Giemsa-stained cytospins. Parasite Multiplication Rate (PMR) was determined via flow cytometry using parasitemia at 64 and 16 hours post infection (hpi) as previously described. Results: In contrast to AS erythrocytes, SS RBCs contain varying amounts of HbF that differ by cell and by individual. In hypoxic SS RBCs with low (3.8%) HbF, P. falciparum parasites remain immature (early trophozoites) in 1, 3, and 5% O2 (Fig. 1) at 36 hpi, when they should have matured into schizonts. However, in SS RBCs with high (22.6%) HbF, 12, 16 and 27% of parasites matured into schizonts in 1, 3 and 5% O2 respectively compared to 0, 0, and 1% in the SS RBCs with 3.8% HbF. Preliminary data also demonstrate that the parasite multiplication rate (PMR), a surrogate of proliferation, in SS RBCs improves with increasing O2 and HbF. Using SS/Hereditary Persistence of Fetal Hemoglobin RBCs with 42% HbF, proliferation in 5% O2 or higher is exponential with a PMR of 2.6 or greater (Fig. 2). In RBCs isolated from SS patients treated with hydroxyurea with HbF of 26.4 or 21%, PMR is 2 or more in 7.5% O2 or greater. Conclusion: These data demonstrate that HbF promotes P. falciparum growth in SS erythrocytes. In addition, the data initiates a resolution of the malaria paradox. HbS in both hypoxic AS and SS surely inhibits P. falciparum growth due to HbS polymerization at low O2. But high levels of anti-sickling HbF observed in erythrocytes from many individuals with SS reverses this inhibition despite the increased content of HbS in SS individuals. Even small increases in P. falciparum proliferation within the broadly compromised SS host may enhance the malaria associated morbidity and mortality seen in this population. These data further suggest the importance of anti-malarial prophylaxis in patients with SS especially those treated with hydroxyurea or anti-sickling agents. Disclosures No relevant conflicts of interest to declare.

Complications of Implantable Venous Access Devices In Patients with Sickle Cell Disease

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1649-1649
Author(s):  
Nirmish Shah ◽  
Daniel Landi ◽  
Radhika Shah ◽  
Jennifer Rothman ◽  
Courtney Thornburg
Keyword(s):  
Sickle Cell Disease ◽  
Bloodstream Infection ◽  
Sickle Cell ◽  
Pediatric Patients ◽  
Conflicts Of Interest ◽  
Bloodstream Infections ◽  
Venous Access ◽  
Categorical Variables ◽  
Cell Disease ◽  
Venous Access Devices

Abstract Abstract 1649 INTRODUCTION: Implantable venous access devices (VADs) are used in sickle cell disease (SCD) for patients with poor venous access to facilitate chronic blood transfusions and management of acute complications. Children and adults with chronic illnesses have high rates of VAD-related complications including bloodstream infection and thrombosis. Patients with SCD may be at higher risk given the presence of functional asplenia and evidence of a hypercoaguable state. The objective of this study was to define the frequency of VAD related bloodstream infections and thrombosis in adults and children with SCD. PATIENTS AND METHODS: We performed a single institution retrospective review of VAD placement in patients with SCD. Subjects were identified through the sickle cell clinic database and the Hospital Information System. Subjects were included if they had SCD, VAD placement between December 1, 1998 to December 1, 2009 and had completed at least 12 months of follow-up. VAD-related bloodstream infection was defined by positive blood culture and VAD-related thrombosis (deep vein thrombosis, superior vena cava syndrome, and pulmonary embolism without lower extremity thrombosis) was defined by imaging. Comparisons were made between pediatric and adult sickle cell patients using Student's t-test for continuous variables and Fisher's exact test was used to compare categorical variables; p<0.05 was considered significant. RESULTS: Of the greater than 800 sickle cell patients followed at our Comprehensive Sickle Cell Center, 32 subjects were eligible for inclusion (median age 20 years, range 1–59). There were 81 VAD placed (median 2.6 VAD per patient, range 1–7) with a total of 49268 catheter days (median 608, range 323–3999). The mean catheter lifespan in adults (1798 days ± 266) was significantly higher than pediatric patients (971 ± 328, p=0.039). There were a total of 66 VAD-related bloodstream infections (1.34 infections per 1000 catheter days) occurring in 17 of 32 (53%) subjects. Although not statistically significant, children had fewer VAD-related bloodstream infections (3 of 10; 30%) compared to adults (14 of 22; 64%, p=0.08). There were 24 catheter-related thromboses (0.49 thromboses per 1000 catheter days) occurring in 10 of 32 (41%) of subjects. Children also had fewer VAD-related thrombosis (1 of 10; 10%) compared to adults (9 of 22; 40%, p=0.08). The overall rates of infection and thrombosis per 1000 catheter days were not significantly different between adult and pediatric patients. CONCLUSION: In summary, we report a long lifespan and low rate of infection in the subjects who had VADs during the study period. Most concerning was a high proportion of adults with catheter-related thrombosis, which adds the burden of anticoagulation to patient management and put patients at risk for post-thrombotic syndrome. Potential lifespan of VADs, risk of bloodstream infection and thrombosis as well as its long-term consequences should be discussed with patients and families considering VAD placement. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Does Hemoglobin S in Sickle Cell Trait and Sickle Cell Anemia Induce Higher Hemostatic Potential?

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4924-4924
Author(s):  
Bhavna Ansuya Mahadeb ◽  
Laurence Rozen ◽  
Denis Fondjie Noubouossie ◽  
Tatiana Besse-Hammer ◽  
Andre Efira ◽  
...  
Keyword(s):  
Steady State ◽  
Sickle Cell ◽  
High Performance ◽  
Conflicts Of Interest ◽  
Sickle Cell Trait ◽  
Peak Velocity ◽  
Protein S ◽  
Lag Time ◽  
Coagulation System ◽  
Significant Difference

Abstract Introduction: Previous studies reported that patients with sickle cell disease (SCD) present with alterations of several factors involved in the coagulation system but also that global hemostatic potential parameters are enhanced in children with SCD suggesting hypercoagulability even at steady state. Such modifications have rarely been studied in adult SCD cohorts or individuals with a sickle cell trait (AS). On the other hand, observation of clinical events suggests that SCD adults patients are at higher risk of thrombosis, while those AS are at higher risk of deep venous and pulmonary thrombosis as well as sudden death after intense physical activity. The aim of our study was to characterise the global haemostatic potential of SS and AS adults. Materials and Methods: Three groups were studied and consisted in 31 controls (group AA), 26 sickle cell trait (group AS) and 29 SCD patients (group SS) at steady state. Hemoglobin phenotype was assessed by combination of cation-exchange high performance chromatography (beta-thal short program BioRad) and capillary electrophoresis (Capillarys systems Sebia Benelux). We used the Calibrated Automated Thrombogram® to measure thrombin generation (TG) on platelet poor plasma (PPP) processed, aliquoted and frozen until needed for further testing in batches. TG was triggered using 1 pM tissue factor (TF) and 4µM phospholipids (PL) in two different conditions: with and without addition of thrombomodulin (TM). The interquartile range for several monitored parameters, namely lag time (min), time to peak (min), velocity index (nM/min), endogeneous thrombin potential (ETP, nM.min) and peak (nM) was compared between the 3 groups using Kruskall-Wallis and Dunn's multiple group comparison tests. Protein C activity (PC), free protein S (PS), factor VIII (FVIII), LDH, Thrombin anti-thrombin complex (TAT) and ultrasensitive CRP (CRP us) were also measured in parallel. Informed written consent was obtained from each subject prior to sampling; the study received approval from the local ethics committee. Results: Without TM, there was a significant difference in peak, velocity index and lag time between the 3 groups (p<0.0001). Highest peak and velocity index, intermediate results and the lowest results were observed for SS, AS and AA groups, respectively. The lowest lag time was obtained for the SS group followed by the AS and AA groups (P< 0.0001).The addition of TM didn’t modify peak, velocity and lag time results. In contrast, ETP was higher for SS and AS group as compared with AA in the presence of TM (p<0.05). PC and PS were lower for the SS group as compared with AA group (p<0.01); PC was intermediate in the AS group. FVIII, CRP us, LDH and TAT were higher for SS as compared with AA (p<0.001). Summary: In this preliminary study we showed that global hemostatic parameters were enhanced in adult SCD patients at steady state. This observation could be related to both a deficiency of the anticoagulant PC pathway and an inflammatory state. Even though we could not highlight hypercoagulability using individual parameters for AS individuals, they showed intermediate profile in global CAT test. In this later group, clinical impact should be investigated in a prospective way. Correlation with HbS level is currently ongoing. Disclosures No relevant conflicts of interest to declare.

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