Hemoglobin Phenotype Research Articles

Sickle cell disease in the Zanzibar Archipelago, the Republic of Tanzania.

Sickle cell disease (SCD) is one of the most severe haemoglobinopathies, a group of blood disorders, typically inherited. The condition affects over 7.7 million people globally and results in more than 370,000 deaths per year. The highest morbidity and mortality rates are seen in Africa and most children with SCD are born in Tanzania. The available literature on SCD morbidity in Tanzania focus primarily on the residents of the mainland, while there is little data available on SCD morbidity among residents of the Tanzanian islands in the Indian Ocean. The aim of the present study was to confirm the presence of sickle cell disease among residents of the Zanzibar Archipelago. The study group consisted of 27 people, residents of Pemba Island in the Zanzibar Archipelago, aged between 2 months and 26 years old, whose at least one parent has been diagnosed with sickle cell anaemia. Blood samples collected from the study participants were tested using HemoTypeSCTM, a rapid, point-of-care diagnostic test. The tests were performed at the Amal Hospital (Chake Chake town, Pemba Island) in June 2023. Sickle cell disease was diagnosed in 11 study subjects (40.7%); their haemoglobin concentration ranged between 6.6 and 8.5 g/dL. The presence of the sickle cell trait (HbAS phenotype) was confirmed in 14 patients (51.9%). Only two of the tested patients had normal haemoglobin phenotype. The results of the present study support the necessity to introduce large-scale population- -based screening for SCD in the Zanzibar Archipelago, especially in infants whose family members have sickle cell anaemia. The introduction of such a programme will help monitor the number of new SCD cases in the region and may potentially reduce infant mortality due to SCD as well as minimize complications from SCD in older children through the adoption of effective disease prevention measures.

Pattern of ABO blood group and haemoglobin electrophoresis (phenotype) among patients presenting with acute Noma in a referral center, Northwest Nigeria

Abstract Background: Noma is a necrotizing destructive disease of the orofacial structures with poorly understood etiopathogenesis. This study aimed to present the pattern of ABO blood group and hemoglobin electrophoresis (phenotype) in patients presenting with acute Noma. Materials and Methods: A retrospective study conducted over five months (November, 2023 to April, 2024) using five year record of patients who presented with acute noma. After obtaining ethical approval, case notes of patients who were managed for acute Noma were retrieved. Patients’ demographic information such as age and sex was recorded. The blood group and the hemoglobin phenotype of the patients were also recorded. Data obtained were analyzed using the Statistical Package for the Social Sciences (IBM SPSS version 25). Results: A total of 205 subjects were recruited, of which there were 100 (48.8%) males and 105 (51.2%) females. The age mean ± standard deviation of the patient was 5.06 ± 3.74 in the range of 9 months–22 years. The blood group O 119 (58.3%) was the highest. The majority of the subjects 179 (87.3%) were found to have rhesus positive blood group antigen. Blood group O was found to have the highest positive rhesus antigen with a significant difference (χ 2 = 9.620, df = 3, P = 0.022). The association between the ABO blood group and the phenotype showed that subjects with blood group O have the highest AA phenotype with no significant difference (χ 2 = 8.855, df = 6, P = 0.182). Conclusion: This study revealed more frequent blood group “O” rhesus positive and “AA” hemoglobin electrophoresis (phenotype) in patients with acute Noma which is similar to the general population in the same geographical region.

Hematological indices among young adults with homozygous sickle cell disease in steady state in southwestern Nigeria: a case–control study

Abstract Background: Sickle cell disease is a genetic abnormality involving the haemoglobin synthesis. Although it is a primary red cell disorder, white blood cells (WBC) and platelets are also affected by the mutation. Aim: To assess and compare the hematological parameters of homozygous sickle cell disease in a steady state with age-matched and sex-matched hemoglobin AA controls. Methods: A total of 150 apparently healthy young adults (18–35 years) participated in this study. They were classified into two groups 88 cases with hemoglobin SS and 62 controls. Venous blood collected into EDTA tubes from participants were used for the full blood count analysis which was done using hematological autoanalyzer (SFRI blood cell counter, H18 light, France). The data were analyzed using descriptive and inferential statistics and the alpha value was set at P value less than 0.05. Results: The mean values for white blood cell, mean corpuscular hemoglobin, mean cell volume, red cell distribution width and platelet count were significantly higher in the Hb SS cohort while the packed cell volume and red cell count were significantly lower in the Hb SS cohort. Conclusions: homozygous sickle cell disease patients have lower values of hemoglobin concentration, PCV, the red cell indices but higher values of white cell count and platelets compared with hemoglobin phenotype AA controls.

Evolution of an extreme hemoglobin phenotype contributed to the sub-Arctic specialization of extinct Steller's sea cows.

The extinct Steller's sea cow (Hydrodamalis gigas; †1768) was a whale-sized marine mammal that manifested profound morphological specializations to exploit the harsh coastal climate of the North Pacific. Yet despite first-hand accounts of their biology, little is known regarding the physiological adjustments underlying their evolution to this environment. Here, the adult-expressed hemoglobin (Hb; a2β/δ2) of this sirenian is shown to harbor a fixed amino acid replacement at an otherwise invariant position (β/δ82Lys→Asn) that alters multiple aspects of Hb function. First, our functional characterization of recombinant sirenian Hb proteins demonstrate that the Hb-O2 affinity of this sub-Arctic species was less affected by temperature than those of living (sub)tropical sea cows. This phenotype presumably safeguarded O2 delivery to cool peripheral tissues and largely arises from a reduced intrinsic temperature sensitivity of the H. gigas protein. Additional experiments on H. gigas β/δ82Asn→Lys mutant Hb further reveal this exchange renders Steller's sea cow Hb unresponsive to the potent intraerythrocytic allosteric effector 2,3-diphosphoglycerate, a radical modification that is the first documented example of this phenotype among mammals. Notably, β/δ82Lys→Asn moreover underlies the secondary evolution of a reduced blood-O2 affinity phenotype that would have promoted heightened tissue and maternal/fetal O2 delivery. This conclusion is bolstered by analyses of two Steller's sea cow prenatal Hb proteins (Hb Gower I; z2e2 and HbF; a2g2) that suggest an exclusive embryonic stage expression pattern, and reveal uncommon replacements in H. gigas HbF (g38Thr→Ile and g101Glu→Asp) that increased Hb-O2 affinity relative to dugong HbF. Finally, the β/δ82Lys→Asn replacement of the adult/fetal protein is shown to increase protein solubility, which may have elevated red blood cell Hb content within both the adult and fetal circulations and contributed to meeting the elevated metabolic (thermoregulatory) requirements and fetal growth rates associated with this species cold adaptation.

Development of the sickle Pan-African research consortium registry in Tanzania: opportunity to harness data science for sickle cell disease.

Sickle cell disease (SCD) is a severe hereditary form of anemia that contributes between 50% and 80% of under-five mortality in Africa. Eleven thousand babies are born with SCD annually in Tanzania, ranking 4th after Nigeria, the Democratic Republic of Congo and India. The absence of well-described SCD cohorts is a major barrier to health research in SCD in Africa. This paper describes the Sickle Pan African Consortium (SPARCO) database in Tanzania, from the development, design of the study instruments, data collection, analysis of data and management of data quality issues. The SPARCO registry used existing Muhimbili Sickle Cell Cohort (MSC) study case report forms (CRF) and later harmonized data elements from the SickleInAfrica consortium to develop Research Electronic Data Capture (REDCap) instruments. Patients were enrolled through various strategies, including mass screening following media sensitization and health education events during World Sickle Cell Day each June and the SCD awareness month in September. Additional patients were identified through active surveillance of previously participating patients in the MSC. Three thousand eight hundred patients were enrolled between October 2017 and May 2021. Of these, 1,946 (51.21%) were males and 1,864 (48.79%) were females. The hemoglobin phenotype distribution was 3,762 (99%) HbSS, 3 (0.08%) HbSC and 35 (0.92%) HbSb +thalassemia. Hemoglobin levels, admission history, blood transfusion and painful events were recorded from December 2017 to May 2021. The Tanzania SPARCO registry will improve healthcare for SCD in Africa through the facilitation of collaborative data-driven research for SCD.

Clinical and laboratory presentation of first-time antenatal care visits of pregnant women in Ghana, a hospital-based study.

The WHO recommends pregnant women attend antenatal clinic at least three times during pregnancy; during the first, second and third trimesters. During these visits, an array of clinical and laboratory tests is conducted. The information obtained plays an important role not only in the management and care of pregnancy, but also guides policies targeted at addressing pregnancy-induced health challenges. This study therefore presents laboratory and clinical information of pregnant women at their first antenatal visits. The study was cross-sectional in design which retrospectively reviewed laboratory and clinical data of pregnant women attending their first antenatal clinic (ANC) at the Comboni Hospital, Volta region, Ghana. The data reviewed included information on hemoglobin level, hemoglobin phenotype, malaria diagnostics, Human Immunodeficiency Virus test (HIV), glucose-6-phosphate dehydrogenase (G6PD) deficiency, Hepatitis C Virus (HCV) test, Hepatitis B Virus (HBV) test, Syphilis test, blood pressure, age, urine glucose, and urine protein. The hemoglobin level was assayed with a hemoglobinometer. Qualitative lateral flow chromatographic immunoassay techniques were used to diagnose the HIV, HCV, HBV, syphilis, and malaria status of the pregnant women. Urine dipstick was used assay for the urine protein and urine glucose, whilst the methemoglobin test was used for the G6PD deficiency and alkaline hemoglobin electrophoresis for hemoglobin phenotype. Data on demographic, anthropometric and vital signs such as age, weight and blood pressure were also collected. Descriptive statistics were performed. Frequency and percentages were used to describe the categorical variables and means and standard deviations used to describe the continuous variables. Hemoglobin S(Hb S) was found in 12.8% of the women with 73.4% having hemoglobin levels below 11.5g/dl. On G6PD deficiency, 1.6% and 0.8% were partially and fully defective respectively. Also, urine protein (1.2%) and glucose (0.4%) were detected. The prevalence of HBV, HCV and malaria were 4.4%, 3.6% and 2.4%, respectively. Anemia in pregnancy was high among the study sample. Malaria and hepatitis infections were observed in the study sample. Policies on maternal health should be targeted at providing better nutritional options, that can enhance the hemoglobin level during pregnancy. Pregnant women should benefit from enhanced surveillance for HIV, HBV, HCV, and syphilis.

Immune Erythrocyte Alloantibodies among Pregnant Women Attending an Antenatal Clinic in a Tertiary Health Facility, Benin City, Nigeria

BACKGROUND: Maternal alloimmunization is associated with adverse outcomes such as hemolytic disease of the fetus and newborn. At-risk pregnant women include those with previous multiple gestations or multiple blood transfusions. This study aimed to determine the proportions and specificities of irregular maternal alloantibodies among antenatal attendees at a federal teaching hospital in Nigeria. An understanding of the pattern of alloimmunization, associated morbidities, and attendant risk factors will guide improved antenatal/perinatal health planning. MATERIALS AND METHODS: A hospital-based, cross-sectional survey was conducted among 150 pregnant women. Data on parity, transfusion history, and other clinical details were obtained with an interviewer administered questionnaire. ABO/Rh D blood groups and hemoglobin phenotypes were retrieved from their antenatal records and confirmed during the study. Alloantibody screening and identification and other serological tests were subsequently performed. Association of independent parameters with other variables was tested using Chi-square analysis or Fisher's exact as appropriate. Level of statistical significance was set at 5% confidence (P = 0.05). RESULTS: Most of the participants (60%) were in their third trimester, while 9.3% were in first trimester of pregnancy. Ninety-one percent of the participants (90.7%) were blood transfusion naïve. Seven of the participants (4.7%) had positive alloantibody screens, of which two (1.33%) were clinically significant maternal alloantibodies (Anti-D and Anti-Lub). No statistically significant association was observed between alloimmunization and variables such as gestational age, parity, hemoglobin phenotype, previous blood transfusions, and Rh D negativity. CONCLUSIONS: The authors recommend routine alloantibody screening for at risk pregnancies.

Renal Abnormalities among Sickle Cell Disease Patients in a Poor Management Setting: A Survey in the Democratic Republic of the Congo.

Background and objectiveSickle cell disease (SCD) is now a well-established cause of renal damage. In the northeast of the Democratic Republic of Congo (DRC), SCD is common. However, sickle cell nephropathy remains unstudied in this region. Thus, this study aimed to assess renal abnormalities in SCD patients in Kisangani (northeastern DRC).MethodsThis cross-sectional study included 98 sickle cell patients selected from six health facilities in Kisangani and 89 healthy non-sickle cell subjects as the control group. Based on a survey form, a clinical examination and biological tests were performed to collect data related to the sex, age, weight, height, pressure, serum creatinine, serum uric acid, urinary albumin/creatinine ratio, and hemoglobin phenotype. We used a spectrophotometer to measure serum creatinine and uricemia, the sickle SCAN® device for hemoglobin phenotype, and an automatic multifunction analyzer for urine albumin/creatinine ratio. Data were entered into an Excel file and analyzed on SPSS 20.0.ResultsThe mean urine albumin-to-creatinine ratio was 11.79±9.03 mg/mmol in SCD patients, significantly higher than in AA (1.69±1.89 mg/mmol) and AS (2.97±4.46 mg/mmol) subjects. The decrease in glomerular filtration rate was more observed in SCD patients with hyperuricemia compared to those with normal uric acid levels. A significantly elevated prevalence of chronic kidney disease was observed among SCD patients (87.8%) compared to 23.8% in AS and 7.7% in AA subjects.ConclusionsThis study highlighted that albuminuria and chronic kidney disease are common in SCD patients in Kisangani. More studies are needed to further document these complications.

Sickle cell disease: caregiver’s awareness and phenotype distribution among children presenting to children emergency of a tertiary hospital in Lagos, Nigeria

Background: Sickle cell disease accounts for significant morbidity and mortality in sub-Saharan Africa and the burden is expected to increase further by 2050. Nigeria is known to bear the highest burden of sickle cell disease in the world with about 2.69–5% of the population affected by the disease.Aim: This study determined awareness of sickle cell disease among caregivers and phenotype distribution of children presenting to children emergency in Lagos University Teaching Hospital (LUTH), Nigeria.Methods: The study was crosssectional and descriptive in design and data was collected using a pretested, structured intervieweradministered questionnaire among 250 caregivers and children. HemoTypeSC™ rapid test kit was used to determine the hemoglobin phenotype in whole blood of the respondents who were consecutively recruited following the caregiver’s consent. The Statistical Package for Social Sciences version 21 software was used for analysis.Univariate and bivariate analyses were carried out with a level of significance set at p ≤ 0.05.Results: The mean age of the children was 50.27±50.91 months. There were more females 141 (56.4%) than males. Almost all 242 (96.8%) caregivers did not know the children’s Hb phenotype. Most 173 (69.2%) of the children had HbAA;55(22.0%) were HbAS; 6(2.4%) were HbAC; 15 and 1 (6.0% and 0.4%) were HbSS and HbSCphenotypes respectively. Education was statistically significant with awareness of SCD (p=0.002) and awareness of SCD was statistically significant with knowledge of prevention (p<0.001) among the caregivers.Conclusion: Awareness of SCD among the caregivers of children was high, although the majority of them did not know the children’s Hb phenotype. Most of the children had HbAA with a high proportion of HbSS and HbSC phenotypes. A routine neonatal/early infant screening program for SCD is highly recommended in Nigeria for early diagnosis and prevention of SCD complications.

Study on HemoTypeSC™ test for the rapid screening of sickle cell disease patients in Government Medical College and Hospital, Ambikapur

Background: Sickle cell disease (SCD), also known as sickle cell anemia, is a dangerous disease in which the body produces an abnormal form of hemoglobin, the protein in red blood cells that transport oxygen throughout the body. The body produces sickle- or crescent-shaped red blood cells as a result of this genetic change. Aims and Objectives: This study aims to study on HemoTypeSC™ test for the rapid screening of SCD patients in Government Medical College and Hospital, Ambikapur. Materials and Methods: Fifty patients have been diagnosed as sickle cell anemia by sickle cell solubility test at Govt. Medical College, Ambikapur, Chhattisgarh,India. All the patients were admitted in the Department of Medicine at Govt. Medical College, Ambikapur, Chhattisgarh,India, from April 1, 2021, to June 1, 2021. Results: The study group (HbSS patients) comprised 22 (42%) males and 28(58%) females.The ages ranged from 1 to 45 years; these 50 patients have been diagnosed as sickle cell anemia by sickle cell solubility test positive at Govt.Medical College, Ambikapur, Chhattisgarh,India. Conclusion: Sickle cell illness can be counted and observed in a variety of ways. Experience includes things such as electrophoresis and hand counting. HemoTypeSC™ is a blood test kit that determines hemoglobin type in whole blood in a short amount of time. At the point of care, this test detects the hemoglobin phenotype HbAA (normal), HbSS and HbSC (SCD), HbCC (hemoglobin C illness), and HbAS and HbAC (carrier or trait). Monoclonal antibodies are highly specific and sensitive to hemoglobin’s A, S, and C. The fetal hemoglobin has no effect. There are no liquid buffer components or requirements for refrigeration. In high temperatures, it remains stable and the test takes only 10 min to complete.

Estimating the risk of child mortality attributable to sickle cell anaemia in sub-Saharan Africa: a retrospective, multicentre, case-control study

Many children with sickle cell disease living in sub-Saharan Africa die before reaching age 5 years. We estimate the child mortality associated with sickle cell anaemia using an indirect approach to overcome the absence of systematic screening at birth. We did a retrospective, multicentre, case-control study in five countries in sub-Saharan Africa (Burkina Faso, Democratic Republic of the Congo, Côte d'Ivoire, Mali, and Senegal). Women with at least one child with a confirmed SS haemoglobin phenotype (sickle cell anaemia) and who had at least three (alive or deceased) children from the same father born more than 5 years ago were recruited at an outpatient consultation in a sickle cell disease care centre. Women who had children without sickle cell disease (control group) were recruited from the same area, with inclusion criteria of being a neighbour or relative of one of the mothers included in the study who had a child with sickle cell anaemia, having no child or other first-degree relative with major sickle cell syndrome, having at least three children (alive or deceased) born more than 5 years ago, and having a confirmed haemoglobin AA phenotype. During the mothers' interview, we collected data concerning the mortality of siblings from the same father of a child with sickle cell anaemia and characteristics of the family, such as age at the time of the survey and the level of education of both parents. Mortality rates were calculated for children younger than 1, 5, and 10 years using the Kaplan-Meier method after excluding the index children. We assumed, as per Mendel law, that in families who have a child with sickle cell anaemia and healthy heterozygous parents, 25% of children born on average have sickle cell anaemia. A multivariate Cox model was used to describe socioeconomic and geographical factors associated with mortality. Between Sept 1, 2017, and Nov 30, 2020, 1563 women who had at least one child with sickle cell anaemia and 4972 women from the same neighbourhood who had children without sickle cell disease were assessed for eligibility. Of 1563 women, 248 were excluded because the genotype of the index child was SC or S β-thalassaemia. 1315 families with cases of sickle cell anaemia and 1243 control families were included in the study. The median age of children (alive) was 14 years (IQR 8-20) in control families and 13 years (8-19) in families with cases of sickle cell anaemia. 5532 [50·6%] of 10 924 children were male. Mortality rates were 15·3% (95% CI 13·3-17·3) for children with sickle cell anaemia younger than 1 year, 36·4% (33·4-39·4) for those younger than 5 years, and 43·3% (39·3-47·3) for those younger than 10 years. Multivariate Cox survival analysis showed that belonging to a family with sickle cell anaemia (hazard ratio [HR] 2·23, 95% CI 1·96-2·54), living in the Democratic Republic of the Congo (HR 1·64, 1·34-2·01), having an older parent (father or mother age had similar effect; HR 1·12, 1·05-1·19 per 10 years of age), or a significantly higher global Multidimensional Poverty Index (HR 1·09, 1·03-1·14), independently increased the risk of mortality. Whereas, living in Senegal (HR 0·70, 95% CI 0·57-0·86) or having a mother with higher education (high school HR 0·66, 0·55-0·80 or advanced HR 0·41, 0·28-0·61) independently decreased the risk of mortality. Although higher than in high-income countries and affected by non-specific socioeconomic factors, the estimated mortality in children with sickle cell anaemia living in sub-Saharan African cities was substantially lower than previous estimates, suggesting an improvement of sickle cell anaemia care in this setting. Fondation Pierre Fabre. For the French translation of the abstract see Supplementary Materials section.

Adiponectin and Disease Severity in Sickle Cell Anemia Patients Attending a Tertiary Health Institution in Nnewi, Southeast Nigeria.

Background: Hemoglobin polymerization in sickle cell anemia (SCA) leads to abnormally rigid and adhesive erythrocytes that obstruct blood vessels, leading to poor tissue perfusion, hence provoking inflammation and damage of surrounding tissues. Adiponectin, a protein hormone, presumptively has anti-inflammatory characteristics, hence may be an important therapeutic target in SCA. Aim: The aim of the study was to evaluate the status of adiponectin and its correlation with disease severity in SCA. Patients and Methods: A total of 84 subjects were recruited for the study comprising 34 homozygous sickle cell (HbSS) subjects (25 in the steady state and nine in the resolving crisis state) and 50 controls (25 heterozygous sickle cell [HbAS] and 25 hemoglobin phenotype AA subjects). The hemoglobin phenotype, adiponectin levels, and full blood counts were evaluated. Anthropometric measurements were also conducted. Results: A significant difference was observed in the mean body mass index between the different hemoglobin phenotype groups and also between the SCA in crisis resolution patients and the control group (p < 0.05). There was no significant difference in the median serum levels of adiponectin in the different hemoglobin phenotype groups and between SCA patients in the steady state compared with those in the crisis resolution state. Also, there was no correlation between disease severity and adiponectin in SCA patients in the steady state (p = 0.87). Conclusion: Our study seems to suggest that in our data set of sickle cell anemia patients in the steady state, adiponectin does not constitute part of the endocrinopathy that affects these patients.

Knowledge, attitude and premarital screening practices for sickle cell disease among young unmarried adults in an urban community in Lagos, Nigeria.

Introductionsickle cell disease (SCD) refers to a group of inherited blood disorders that are life-long and affect many people globally. An estimate of 2.3% of the Nigerian population suffer from SCD and about 25% of adults have the sickle cell gene. Premarital screening for sickle cell gene is considered one of the methods of preventing new births of children with SCD among the young adults. The study assessed the knowledge, attitude, willingness to take premarital screening test for SCD and factors influencing knowledge among young unmarried adults in an urban community in Lagos, Nigeria.Methodsthe study was cross-sectional descriptive among 300 respondents who were selected using multistage sampling technique. Data were collected using a pre-tested, interviewer-administered questionnaire and analyzed using SPSS software, version 25. Univariate and bivariate analysis were conducted with level of significance at p ≤ 0.05.Resultsthe mean age of respondents was 21.2± 3.5 years, and most 188 (62.7%) were males. About 139 (46.3%) and 165 (55.0%) of the respondents respectively had good knowledge and positive attitude towards SCD and premarital screening. Only 43% of the respondents knew their haemoglobin phenotype, however, majority (92.4%) were willing to have Hb phenotype test done. Knowledge of SCD and premarital screening was statistically significant with age, level of education and occupation of respondents (p<0.001).Conclusionthis study found less than half of the respondents with good knowledge, about half had positive attitude and poor premarital screening practices of SCD. Therefore, community-based health education and awareness programs on SCD and premarital screening among young adults is recommended.

Pattern of Haemoglobin Phenotypes and the Clinical Identity of Clients Tested at a Private Diagnostic Center in South-West Nigeria

Background: Haemoglobinopathies are diseases of global importance and the countries with high disease burdens have inaccurate national data on the incidence of the various haemoglobin (Hb) phenotypes.&#x0D; Objective: To review the Hb phenotype distribution, the referral identity of patients, and the clinical reasons for phenotyping.&#x0D; Methods: A retrospective descriptive study conducted at a private diagnostic laboratory in Lagos, South-West, Nigeria. The anonymous results of Hb phenotypes of the patients determined using gel electrophoresis were retrieved from the laboratory information system (LIS).&#x0D; Results: There were 942 patients: 519(55.1%) males and 423(44.9%) females with median ages 30yrs (11months-89yrs) vs 27yrs (9months-89yrs), p=0.0018. The phenotypes were HbAA, 592(63.2%); HbAS(26.4%); HbSS(7.1%); HbAC(2.1%), HbSC(0.7%) and HbCC(0.4%). Of the total, 757(80.4%) were referred by health care providers and 185(19.6%) were selfreferred, and there was no association between gender and referral identity of patients. However, there were more males [353(46.6%)] with clinical reasons for referrals than females [94(12.4%)], p&lt;0.0001, and annual check was the commonest reason for Hb phenotyping.&#x0D; Conclusion: Most patients were referred for Hb phenotyping and an annual health check is the commonest reason for phenotype requests. This emphasizes the need for policies to support national Hb phenotype/genotype screening programmes to aid the early detection of sickle cell disease.&#x0D; Keywords: Haemoglobin phenotype; clinical identity; private laboratory.

Ovarian reserve in nigerian women with sickle cell anaemia: a cross- sectional study

IntroductionSickle cell disease is the most common monogenetic disorder worldwide. There have been reports of endocrine dysfunction and gonadal failure among affected individuals, especially in males. The findings on ovarian reserve and failure in women with sickle anaemia have been inconsistent.Aim and objectiveThe aim of this study was to determine and compare the ovarian reserve of Nigerian women with and without sickle cell anaemia attending a University Teaching Hospital.Study DesignThis cross-sectional study was carried out at the Adult Sickle Cell Clinic and the Community Health Clinic of the Lagos University Teaching Hospital.MethodologyA total of 166 participants who met the selection criteria, were recruited for the study. The study population consisted of two groups of women matched for age: 83 women with HbSS and 83 women with HbAA. The haemoglobin phenotype of each participant was determined on alkaline electrophoresis (pH 8.4) before analysis. Serum Anti-Mullerian Hormone (AMH) was determined using Enzyme-linked immunosorbent assay (ELISA) method (Calbiotech Inc. USA, Catalog no AM448T).ResultsThe mean ± SD of serum AMH level in women with HbSS was 3.64 ± 0.65 ng/mL and was lower than that of women with HbAA 7.35 ±1.19 ng/mL (p < 0.001). Serum AMH negatively correlated with age in both study groups (HbAA and HbSS). Also, a significant negative correlation was found between serum AMH and BMI in women with HbAA.ConclusionThe study showed diminished ovarian reserve in women with HbSS when compared to age-matched women with HbAA.

Immune erythrocyte antibodies in adult patients with sickle cell disease and blood donors in Lagos, Nigeria: a comparative study.

Abstract Sickle cell disease (SCD) poses a major public health challenge in sub-Saharan Africa, including Nigeria. Blood transfusion is a mainstay in SCD treatment. Erythrocyte alloimmunization is known to complicate the transfusional care of patients with SCD. Immune alloantibodies are associated with hemolytic transfusion reactions and transfusion refractoriness. We aimed to determine the prevalence, specificities, and clinical associations/risk factors of immune erythrocyte alloantibodies among adult patients with SCD compared with healthy blood donors in Lagos, Nigeria, through a cross-sectional study. All participants were interviewed using a structured questionnaire to obtain details on bio-data, hemoglobin phenotype, blood transfusion history, and SCD history where relevant. Blood specimens obtained from each participant were subjected to antibody screening/identification using tube agglutination method. The mean age of the SCD participants and healthy blood donors was 27.92 and 29.04 years, respectively. The majority (72.5%) of the SCD participants had received at least 1 unit of red blood cell (RBC) transfusion in their lifetime, compared with only 7.5 percent of blood donors. Six SCD participants (7.5%) tested positive for atypical erythrocyte alloantibodies, with none among blood donors. Most of the antibodies (75%) belonged to the Rh blood group system. The most frequent antibody was anti-E, followed by anti-C and anti-D. Advancing age (30 years or more), recent transfusions (last 4 weeks), higher transfusion rates, and established renal disease were significantly associated with alloimmunization (p values of 0.026, 0.043, 0.002, and 0.043, respectively). This study suggests blood transfusion as a strong risk factor for RBC alloimmunization in SCD patients. Extended RBC phenotyping is recommended for all patients with SCD, especially those receiving regular transfusions.

Prevalence, Determinants and Impact of Haemoglobin Phenotype Misdiagnosis Among Parents of Children Living with Sickle Cell Disease in Nigeria

Prevalence, Determinants and Impact of Haemoglobin Phenotype Misdiagnosis Among Parents of Children Living with Sickle Cell Disease in Nigeria

Hemechip: An Automated Portable Microchip Electrophoresis Platform for Point-of-Care Sickle Cell Disease Screening

Sickle Cell Disease (SCD) affects more than 14 million people globally, primarily in economically disadvantaged populations. Its management requires early diagnosis, monitoring, and treatment throughout the lifespan of the patient. Early diagnosis of SCD remains a challenge in the developing world due to requirements for sophisticated lab equipment and skilled personnel. American Society of Hematology with other organizations launched the Sickle Cell Disease Coalition, calling for improved patient care. In low-income countries, notably those in Sub-Saharan Africa, the mortality rate for children <5 years with SCD is 50-80%, without early diagnosis and basic care. Access to testing is lacking in these areas since existing SCD screening methods are expensive and resource intensive. The situation calls for an accurate and affordable diagnostic tool designed for point-of-care (POC). To address this need, we developed HemeChip, an accurate, affordable, and rapid “microchip electrophoresis” test, packaged in a small, easy-to-use, and low-cost mass-producible platform. HemeChip identifies SCD and other critical hemoglobinopathies as well as provides relative percentages of hemoglobin types. HemeChip is the first paper-based microchip electrophoresis platform that performs both qualitative and quantitative analysis of hemoglobins. Here, we build on our previous work (Blood 2015 126:3379) by presenting an initial clinical performance analysis of HemeChip's results, compared with High Performance Liquid Chromatography (HPLC), the clinical gold standard.The compact single-use microchip of the HemeChip platform encompasses cellulose acetate paper, in which the hemoglobin separation takes place, as well as integrated stainless-steel electrodes (Fig. 1A). The HemeChip test is performed in four steps: (i) finger/heel prick equivalent amount of whole blood (diluted and lysed) is applied to the microchip (Fig. 1A); (ii) microchip is placed inside the HemeChip reader (Fig. 1B); (iii) real time images of the hemoglobin electrophoresis are captured during the test by the portable reader; and (iv) custom built-in software automatically analyses the results real-time, extracts relevant peak positions, and performs quantitative analysis (Fig. 1C) similar to HPLC. Total procedure takes less than 10 minutes.HemeChip reliably detects hemoglobin types and categorizes patient samples as normal (Hb AA), sickle cell trait (Hb SA), sickle cell anemia (Hb SS), and sickle-hemoglobin C disease (Hb SC) (Table 1). All 77 blood samples tested were obtained under Institutional Review Board (IRB) approval. Tests were performed by both experienced and minimally-trained personnel. Test results for both categories did not introduce discrepancy or variation in accuracy. The HemeChip tests correctly categorized patient samples as Hb AA, Hb SA, Hb SS, and Hb SC with 96.6%-100% accuracy compared with HPLC (Table 1).HemeChip provides high accuracy for hemoglobin phenotype detection and excellent compliance with the clinical gold standard for quantification of the results, which suggests that the HemeChip platform could address the unmet need for screening in regions where SCD is prevalent. Field-testing of HemeChip for SCD screening is ongoing in sub-Saharan Africa.Acknowledgments: This work was supported by: Case-Coulter Translational Research Partnership, Clinical and Translational Science Collaborative of Cleveland (National Center for Advancing Translational Sciences), NIH Center for Accelerated Innovation at Cleveland Clinic, and Center for Integration of Medicine & Innovative Technology.Figure 1: HemeChip overview and initial clinical testing results. (A) Illustration of hemoglobin separation during a HemeChip test. (i) initial, (ii) intermediate, and (iii) final phase of the separation in HemeChip. (B) (i) Portable HemeChip Reader with custom built-in analysis software, (ii) Ssingle use HemeChip cartridge microchip after a test. (C) HemeChip image analysis showing identification and quantification for an Hb SA blood sample. (i) Captured image of hemoglobin separation. (ii) Averaged pixel plot along the HemeChip length reveals intensity peaks and hemoglobin types. (iii) Baseline corrected area under curve determines the relative percentage of hemoglobins compared with HPLC. [Display omitted] DisclosuresLittle:Hemex Health: Equity Ownership. Gurkan:Hemex Health: Employment, Equity Ownership.

Safety of 3 Tesla Magnetic Resonance Imaging in Patients with Sickle Cell Disease.

Sickle cell disease (SCD) is a well-characterized hemoglobinopathy affecting more than 20 million individuals worldwide and carries an increased risk of cerebral vasculopathy, cerebral infarct, and stroke. As mechanisms of cerebral infarction in SCD are partly attributable to microvascular vaso-occlusive crises, manifesting as altered cerebral blood flow and associated impaired oxygen delivery, magnetic resonance imaging (MRI) methods that can quickly provide a comprehensive perspective on structural and functional disease status, without exogenous contrast administration or ionizing radiation, have emerged as crucial clinical tools for surveillance. However, early ex vivo MRI work in suspended erythrocytes containing hemoglobin S at 0.35 Tesla (T) suggested that sickled erythrocytes can orient preferentially in the presence of an external magnetic field, and as such, it was suggested that MRI exams in sickle cell hemoglobinopathy could induce vaso-occlusion. While this observation has generally not impacted clinical imaging in individuals with SCD, it has led to resistance for some sickle cell studies within the engineering community among some imaging scientists as this early observation has never been rigorously shown to be unconcerning. Here, we performed MRI at the clinical field strength of 3 T in 172 patients with SCD, which included standard anatomical and angiographic assessments together with gold standard diffusion-weighted imaging (DWI; spatial resolution = 1.8 × 1.8 × 4 mm; b-value = 1000 s/mm2) for acute infarct assessment (performed approximately 20 min after patient introduction to the field isocenter). The presence of vasculopathy, as well as chronic and acute infarcts, was evaluated by two independent board-certified radiologists using standard clinical criteria. In these patients (52.3% female; mean age = 19.6 years; age range = 6–44 years), hematocrit (mean = 25.8%; range = 15–36%), hemoglobin phenotype (87.8% HbSS variant), presence of silent infarct (44.2%), and overt chronic infarct (13.4%) were consistent with a typical SCD population; however, no participants exhibited evidence of acute infarction. These findings are consistent with 3 T MRI not inducing acute infarction or vaso-occlusion in individuals with SCD and suggest that earlier low-field ex vivo work of erythrocytes in suspension is not a sufficient cause to discourage MRI scans in patients with SCD.

Evaluation of the diagnostic accuracy of a hemoglobin S and C screening test: Sickle Scan

New tools for the rapid diagnosis of hemoglobinosis could encourage the extension of their screening in Africa. Our goal was to assess the analytical performances of a rapid hemoglobin S and C detection test, the Sickle Scan. This was a cross-sectional study carried out in March 2019 at the Yopougon Teaching Hospital. The subjects followed for hemoglobinosis as well as the subjects seeking out an electrophoresis of their hemoglobin were included. We carried out the hemogram, the electrophoresis of hemoglobin at alkaline pH (reference method) coupled with the metabisulfite sickling test (Emmel test) and the rapid detection test to be evaluated. This immunochromatographic test is capable of detecting hemoglobins A, S, and C, and to infer the hemoglobin phenotype from there. The study recruited 191 individuals. The test detected hemoglobins S and C with a sensitivity of 99.4% and 97.7% respectively; a specificity of 93.3% and 99.3%. The positive likelihood ratio for hemoglobins S and C was 15 and 144 respectively. The negative likelihood ratio was 0.01 for hemoglobin S, and 0.02 for hemoglobin C. The intrinsic characteristics obtained make this test an interesting screening tool for hemoglobinosis S and C. &#x0D; Keywords: Diagnostic test, hemoglobinosis, Abidjan, sensitivity, specificity.