Sickle cell-haemoglobin E (HbSE) compound heterozygosity: a clinical and haematological study

Clinico-Hematological Profile in Hemoglobin SE Disease: A Case Series from a Tertiary Care Centre

Hemoglobin SE (HbSE) disease are rare globally and there is paucity of literature regarding this condition. Cases reported in the Indian scenario so far have been limited to the tribal populations. This case series aims to highlight the rarity of this double heterozygous state and to raise awareness of its community prevalence beyond the tribal population. This is a case series over a 5-year observation period with six cases of double heterozygosity for HbS and HbE in our tertiary care centre. Four cases were in the 8-15 years' age group and 2 cases of 24-25 years' age group reported for initial evaluation due to easy fatigability and weakness: Two cases were siblings with history of consanguineous marriages in the family. Mild Pallor, variable icterus, spleen was just palpable in three of the cases and low MCV recorded in all cases. Sickling tests were positive and high performance liquid chromatography (HPLC) revealed both HbS > 50% and HbE fractions ≥ 25%. It's important to detect this rare condition, prevalent in consanguineous marriages as dreaded complications like sickling crisis may manifest during pregnancy and air travel. Detection and genetic counselling is important for prognosis, planning follow up and therapy for this uncommon double heterozygous state.

Profiling of 35 Cases of Hb S/Hb E (HBB: c.20A>T/HBB: c.79G>a), Disease and Association with α-Thalassemia and β-Globin Gene Cluster Haplotypes from Odisha, India

Hb S/Hb E (HBB: c.20A>T/HBB: c.79G>A) is an uncommon variant of sickle cell disease resulting from coinheritance of Hb S and Hb E. Clinico-hematological and biochemical parameters of 35 cases of Hb S/Hb E disease were studied and compared with 70 matched cases of homozygous sickle cell disease (Hb SS) and Hb S/β-thalassemia (β-thal) with IVS-I-5 (G>C) (HBB: c.92+5G>C). The influence of α-thal and that of of β-globin gene cluster haplotypes among Hb S/Hb E disease was also studied. Statistical analysis was done using GraphPad InStat version 3.06. Of the 35 cases, 20 (57.14%) had a moderate clinical presentation. Mean lactate dehydrogenase (LDH) level, vaso-occlusive crises (VOCs) per year, and annual blood transfusion requirements were significantly lower in Hb S/Hb E cases than in the other two groups. The hemoglobin (Hb) and packed cell volume (PCV) levels were significantly high in Hb S/Hb E cases with α-thal and these cases were associated with microcytic-hypochromic anemia. α-Thalassemia did not influence clinical presentation in Hb S/Hb E cases. The β-globin gene cluster haplotypes of 70 alleles of Hb S/Hb E revealed an association of five typical haplotypes [Arab-Indian (A-I), Benin, Bantu, Cameroon and Senegal] in 95.71% cases. Hb S/Hb E disease exhibit asymptomatic to moderate phenotypic expression. However, further in-depth studies on Hb S/Hb E will help in reducing the disease burden especially in high-risk countries like India.

Compound heterozygosity for hemoglobin S and hemoglobin E in a family of Proto-Australoid origin: a case report

Background

Hemoglobin S and E are commonly occurring hemoglobin variants among distinctly separate tribal populations of Central and Northeast India, respectively. Combined heterozygosity for hemoglobin S and E or hemoglobin SE disease is a benign clinical condition with rare incidence. Reports of approximately 46 hemoglobin SE cases are available worldwide. We conducted a screening program to study the prevalence of hemoglobin variants among the tribal population working in the tea estates of Northeast India. A total of 551 subjects were screened, and complete blood count was performed. Based on their hematological profiles, hemoglobin typing was done for 218 subjects.

Case presentation

We describe a case of an adolescent male of Munda tribe diagnosed as double heterozygous for hemoglobin S and E. On screening of the nuclear family of the subject, the mother was found to have hemoglobin E disease and father as hemoglobin S trait. Both siblings of the subject were diagnosed as hemoglobin E trait.

Conclusion

This is the first case of compound heterozygous for hemoglobin S and E to be reported from the tea tribes of Assam, India.

Acute chest syndrome in sickle cell disease/HBE patient, A case report

The presented case will shed some light on one of the rarest complications of HBSE disease, which is acute chest syndrome, and will highlight the management of that complication.

Manifestations of HbSE sickle cell disease: a systematic review

BACKGROUND

Sickle cell disease (SCD) is commonly encountered in Africa and Middle Eastern countries. The causative mutation in the gene encoding the hemoglobin subunit β (HBB) leads to various genotypic variants of the disease. This results in varied phenotypes, with a spectrum of complications, from benign to fatal. Hemoglobin SS (HBSS) genotype is associated with most of these complications; hence, it is a severe form of SCD. On the other hand, rare genotypes such as hemoglobin SE (HBSE) are considered benign. There is limited literature about the clinical manifestations and characteristics of patients with HBSE. We pooled all available data describing the phenotypic manifestations of HBSE heterozygote worldwide to perform a systematic review.

METHODS

We performed a systematic review according to PRISMA guidelines using PubMed, SCOPUS, and Google Scholar databases. Two independent reviewers (FA and IK) evaluated studies for eligibility and extracted data. We synthesized data on demographics, manifestations, and management of HBSE disease. PROSPERO Registration Number: CRD42021229877.

RESULTS

We found 68 HBSE patients reported in the literature. 24 cases were extracted from case reports whereas 44 cases from case series and retrospective studies. Turkey reported the highest number of patients (n = 22). 32 (47%) of the patients were males. The mean age was 20.9 ± 18.26 years. The mean HBS and HBE percentages were 61.1% ± 7.25% and 32.3% ± 5.06%, respectively, whereas the mean hemoglobin was 11.64 ± 1.73 g/dl. Reported manifestations of HBSE disease included acute vaso-occlusive pain crisis (n = 22, 32.3%), splenomegaly (n = 11, 16.1%), hemolytic anemia (n = 10, 14.7%), infections (n = 8. 11.7%), bone infarction (n = 4, 5.8%), gallstones (n = 3, 4.4%), venous thromboembolism (VTE) (n = 2, 2.9%) and stroke (n = 2, 2.9%), and hematuria (n = 2, 2.9%). Death due to HBSE complications was reported in three patients.

CONCLUSION

HBSE is a rare genotypic variant of SCD. It has been considered a benign form; however, there are multiple reports of severe complications. Severe complications observed in HBSE disease include vaso-occlusive crisis, acute chest syndrome, stroke, bone marrow embolism, and death.

OCCURRENCE OF UNUSUAL HAEMOGLOBINOPATHIES IN BALOCHISTAN: HB SD AND HB SE - PRESENTATION WITH OSTEOMYELITIS

OBJECTIVE

To describe two cases of unusual variants of sickle cell disease.

CASE DESCRIPTION

We present two cases of sickle cell disease variants (haemoglobinopathies), from unrelated families, in the state of Balochistan (Pakistan). One was diagnosed with sickle cell disease in the haemoglobin electrophoresis, whereas the other was diagnosed with sickle cell SE disease. Both were diagnosed based on the presentation of osteomyelitis.

COMMENTS

Haemoglobin SD disease (Hb SD) and haemoglobin SE disease (Hb SE) are rare haemoglobinopathies in the world. The lack of available literature suggests that both are variants of sickle cell disease (SCD), with heterogeneous nature. The prevalence of sickle cell disease with compound heterozygotes was found at a variable frequency in the population of the Asian Southeast. The frequency of osteomyelitis in SCD is 12 to 18%, but its occurrence among variant haemoglobinopathies is little reported. Both reported cases presented with osteomyelitis as a characteristic of the disease presentation.

Sickle cell retinopathy: improving care with a multidisciplinary approach

Sickle cell retinopathy (SCR) is the most representative ophthalmologic complication of sickle cell disease (SCD), a hemoglobinopathy affecting both adults and children. SCR presents a wide spectrum of manifestations and may even lead to irreversible vision loss if not properly diagnosed and treated at the earliest. Over the past decade, multidisciplinary research developments have focused upon systemic, genetic, and ocular risk factors of SCR, enabling the clinician to better diagnose and manage these patients. In addition, newer imaging and testing modalities, such as spectral domain-optical coherence tomography angiography, have resulted in the detection of subclinical retinopathy related to SCD. Innovative therapy includes intravitreal injection of an anti-vascular endothelial growth factor (eg, Lucentis^® [ranibizumab] or Eylea^® [aflibercept]) which appears comparatively safe and efficient, and may be combined with laser photocoagulation (LPC) for proliferative SCR. The effect of LPC alone does not significantly lead to the regression of advanced SCR, although it helps in avoiding hemorrhage and sight loss. This comprehensive article is based on 10-years retrospective (2007–2017) studies. It aims to present advances and recommendations in SCR theranostics while pointing out the requirement of combinatorial approaches for better management of SCR patients. To reach this goal, we identified and analyzed randomized original and review articles, clinical trials, non-randomized intervention studies, and observational studies using specified keywords in various databases (eg, Medline, Embase, Cochrane, ClinicalTrials.gov).

Unrecognized hemoglobin SE disease as microcytosis

Hemoglobin SE disease was first described during the 1950s as a relatively benign microcytosis, but increasing prevalence has revealed a predisposition towards vasoocclusive sickling. Recognition of SE hemoglobinopathies' potential complications is crucial so medical measures can be utilized to avoid multiorgan injury.

Hemoglobin SE Disease in Hatay, in the Southern Part of Turkey

Double heterozygosity for hemoglobin (Hb) E and S, known as HbSE disease, is a rare, clinically benign condition involving mild hemolysis. Only 25 cases have been reported to date. The current literature generally associates HbSE with a benign clinical course, although vaso-occlusive complications have been reported. Although only single case reports were previously available, we have observed 20 cases of HbSE and wish to report them. We examined the records of patients presenting to our hemoglobinopathy center in 2001–2013. High performance liquid chromatography (HPLC) was used for hematological assessment of blood samples with ethylenediaminetetraacetic acid. Eight patients were male and 12 female. Mean hemoglobin electrophoresis values were Hb A1: 6.3%, Hb E 34.5%, HbS: 59.5% and Hb F: 1.9%. Three patients (15%) were symptomatic with vaso-occlusive crisis and one had cerebral stroke. These were siblings. The patient with cerebral stroke was using hydroxyurea. The incidence of HbSE disease is rising due to population admixtures and racial intermarriages. Increased numbers of cases of HbSE have been detected after premarital hemoglobinopathy screening in the Antakya and Çukurova regions of Turkey. The aim of this study was to report large numbers of patients with HbSE diagnosed through the routine HPLC method. The secondary aim was to emphasize that severe vaso-occlusive crisis such as infarction symptoms could be seen in HbSE. E，S型双杂合性血红蛋白，被称为HbSE症，是一种罕见的，临床上呈良性的病症，通常伴有轻度溶血症状。迄今为止只有25个关于此病症的报告。当前通常把HbSE症是作为一种良性病患，尽管已有报告显示出其梗塞并发症的存在。虽然只有极少的相关报告，我们仍研究了20个HbSE病例，并希望能陈述我们的发现。 我们检查了2001–2013年患者在我们血红蛋白病中心提交的检测记录。高效液相色谱法（HPLC）及乙二胺四乙酸被采用以评估收集到的血液样本。患者为8名男性，12名女性。他们的平均血红蛋白电泳值分别为Hb A1: 6.3%、Hb E:34.5%、Hb S:59.5%,Hb F:1.9%。其中3位（15%）患者患有梗塞的并发症，一位患有脑卒中。这三名患者是兄弟姐妹。患有脑卒中的患者当时使用过羟基脲。HbSE症发病率的上升是由于人口及人种间的混血。在土耳其Antakya 和Çukurova 地区的婚前血红蛋白病的筛查中，发现了HbSE症病例的增加。该研究的目的是报告大量通过高效液相色谱法诊断的HbSE症病例。次要目的是强调例如梗塞的严重并发症会由HbSE症引发。

First Reported Case of Proliferative Retinopathy in Hemoglobin SE Disease

We report the first case of proliferative sickle cell retinopathy in a patient with hemoglobin SE (Hb SE) disease. Only a few dozen cases of Hb SE disease have been reported previously, and none had evidence of proliferative retinopathy. A 56-year-old African American man presented to our clinic for routine examination and was found to have sea-fan peripheral neovascularization bilaterally without maculopathy. Hemoglobin analysis revealed Hb SE heterozygosity. Sector laser photocoagulation to areas of nonperfusion in both eyes resulted in regression of the peripheral neovascularization over a period of 6 months. Although Hb SE disease is rare, the incidence of Hb SE disease is postulated to rise in the future. Awareness of its potential ocular complications is needed to appropriately refer these patients for screening.

Back pain: the sole of presentation of sickle cell disease

Diagnosing back pain in children and adolescents can be a challenge to health care providers. Although studies show that more than half of the cases of back pain in children are of non-organic cause, missing the right diagnosis could be detrimental. We present a case of lower back pain in a ten-year-old male whom we eventually diagnosed with hemoglobin SE mutation, which responded well to pain management. Hence, sickle cell disease with vaso-occlusive crisis should be incorporated into the list of differential diagnoses in children with back pain.

Hemoglobin variant analysis of whole blood and dried blood spots by MS

MS allows for the unequivocal diagnosis of hemoglobin variants, or hemoglobinopathies. Hemoglobinopathies are the most common inherited disorder and there is a need for rapid detection of clinically significant variants, such as sickle hemoglobin, which is responsible for sickle cell disease. In this review, we describe the development of MS approaches for the determination of hemoglobin variants from both whole blood samples and dried blood spots. MS approaches that are suitable for population screening are discussed, as are recent advances in direct surface analysis of dried blood spots.

Sudden death after exercise in an adolescent with hemoglobin SE

Hemoglobin (Hb) S and Hb E are the most common variant hemoglobins, but because of the geographical separation of the areas where they are prevalent, the combination of the 2 is uncommon. Approximately 46 cases of hemoglobin SE compound heterozygosity have been reported. No deaths from the condition have been reported previously, whereas death after vigorous physical activity in individuals with sickle cell trait (hemoglobin AS) has been described in a few case reports. Here we report previously undiagnosed hemoglobinopathy SE in a 12-year-old American boy who collapsed during football practice and had a cardiac arrest on the field after a brief lucid interval. The autopsy was significant only for postmortem intravascular sickling. A postmortem hemoglobin electrophoresis test revealed 57% S, 34% E, and 1% F hemoglobins. The death is attributed to cardiac ischemia from functional vaso-occlusion by sickled erythrocytes.

Susceptibility to invasive bacterial infections in children with sickle cell disease

Individuals with sickle cell disease (SCD) demonstrate an increased susceptibility to invasive bacterial infections (IBI). The most common organisms causing IBI are Streptococcus pneumoniae, nontyphi Salmonella species and Haemophilus influenzae type b (Hib). IBI are the most common causes of death in children below 5 years of age with SCD. Increased susceptibility to IBI is because of several factors including dysfunctional antibody production and opsonophagocytosis as well as defective splenic clearance. Early diagnosis of Hib and pneumococcal infections combined with antibiotic prophylaxis and immunization programs, could lead to significant improvements in mortality, especially in Africa.