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1.
IUBMB Life ; 74(5): 474-487, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35184374

RESUMEN

Hemoglobin oxidation due to oxidative stress and disease conditions leads to the generation of ROS (reactive oxygen species) and membrane attachment of hemoglobin in-vivo, where its redox activity leads to peroxidative damage of membrane lipids and proteins. Spectrin, the major component of the red blood cell (RBC) membrane skeleton, is known to interact with hemoglobin and, here this interaction is shown to increase hemoglobin peroxidase activity in the presence of reducing substrate ABTS (2', 2'-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic Acid). It is also shown that in the absence of reducing substrate, spectrin forms covalently cross-linked aggregates with hemoglobin which display no peroxidase activity. This may have implications in the clearance of ROS and limiting peroxidative damage. Spectrin is found to modulate the peroxidase activity of different hemoglobin variants like A, E, and S, and of isolated globin chains from each of these variants. This may be of importance in disease states like sickle cell disease and HbE-ß-thalassemia, where increased oxidative damage and free globin subunits are present due to the defects inherent in the hemoglobin variants associated with these diseases. This hypothesis is corroborated by lipid peroxidation experiments. The modulatory role of spectrin is shown to extend to other heme proteins, namely catalase and cytochrome-c. Experiments with free heme and Raman spectroscopy of heme proteins in the presence of spectrin show that structural alterations occur in the heme moiety of the heme proteins on spectrin binding, which may be the structural basis of increased enzyme activity.


Asunto(s)
Hemoproteínas , Antioxidantes , Catalasa/genética , Hemo , Hemoglobinas/genética , Hemoglobinas/metabolismo , Peroxidasa/genética , Peroxidasas/genética , Especies Reactivas de Oxígeno , Espectrina/química , Espectrina/genética , Espectrina/metabolismo
2.
Acta Haematol ; 145(3): 334-343, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34753145

RESUMEN

BACKGROUND: Leg ulcers are a frequent complication in patients with the inherited hemoglobin disorders. In thalassemia, the literature is limited, and factors associated with the development of leg ulcers in hemoglobin E (HbE) beta thalassemia, the most common form of severe beta-thalassemia worldwide, have not previously been reported. METHODS: We reviewed all available medical records of patients with HbE beta thalassemia to document the onset of leg ulcers at the 2 largest treatment centers in Sri Lanka. We reviewed the literature to identify studies reporting outcomes of interventions for ulcers in severe thalassemia. RESULTS: Of a total of 255 actively registered patients with HbE thalassemia in the 2 centers, 196 patient charts were evaluable. A leg ulcer with a documented date of onset was recorded in 45 (22%) of 196 evaluable patients, aged (mean ± SEM) 22.2 ± 1.4 years. Most had been irregularly transfused; steady-state hemoglobin was 6.4 ± 0.2 g/dL. Treatment achieving healing in 17 patients included transfusions, antibiotics, oral zinc, wound toileting, and skin grafting. CONCLUSION: Leg ulcers may be more common in HbE beta thalassemia than in other forms of thalassemia. A systematic approach to treatment will be needed to document the prevalence and factors placing such patients at risk for leg ulcers. Controlled trials to evaluate the optimal treatment of this common complication are indicated.


Asunto(s)
Hemoglobina E , Úlcera de la Pierna , Talasemia , Talasemia beta , Humanos , Úlcera de la Pierna/complicaciones , Úlcera de la Pierna/terapia , Talasemia/complicaciones , Cicatrización de Heridas , Talasemia beta/complicaciones , Talasemia beta/terapia
3.
Acta Haematol ; 144(6): 660-671, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34535581

RESUMEN

INTRODUCTION: ß-Thalassemia/hemoglobin E represents one-half of all the clinically severe ß-thalassemias worldwide. Despite similar genetic backgrounds, patients show clinical heterogeneity ranging from nearly asymptomatic to transfusion-dependent thalassemia. The underlying disease modifying factors remain largely obscure. METHODS: To elucidate the correlation between ineffective erythropoiesis and ß0-thalassemia/hemoglobin E (HbE) disease severity, in vitro culture of erythroid cells derived from patients with different clinical symptoms was established. Cell proliferation, viability, and differentiation were investigated. To identify potential molecular mechanisms leading to the arrested erythroid maturation, the expression levels of erythropoiesis modifying factors were measured. RESULTS: The ß0-thalassemia/HbE cells exhibited enhanced proliferation, limited differentiation, and impaired erythroid terminal maturation but did not show accelerated erythroblast differentiation and increased cell death. Erythroblasts derived from mild patients showed the highest proliferation rate with a faster cell division time, while erythroblasts derived from severe patients displayed extremely delayed erythroid maturation. Downregulation of growth differentiation factor 11 and FOXO3a was observed in mild ß0-thalassemia/HbE erythroblasts, while upregulation of heat shock protein 70 and activin receptor 2A was revealed in severe erythroblasts. DISCUSSION/CONCLUSION: The degree of erythroid expansion and maturation arrest contributes to the severity of ß0-thalassemia/HbE patients, accounting for the disease heterogeneity. The findings suggest a restoration of erythroid maturation as a promising targeted therapy for severe patients.


Asunto(s)
Eritroblastos/metabolismo , Hemoglobina E/análisis , Talasemia beta/patología , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Adolescente , Adulto , Apoptosis , Estudios de Casos y Controles , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Eritroblastos/citología , Eritropoyesis , Femenino , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Hemoglobina E/genética , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven , Talasemia beta/genética
4.
BMC Public Health ; 21(1): 1177, 2021 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-34154562

RESUMEN

BACKGROUND: Thalassemia, an inherited hemoglobin disorder, has become a global public health problem due to population migration. Evidence-based strategies for thalassemia prevention in migrants are lacking. We characterized barriers to thalassemia screening and the burden of thalassemia in migrant workers in Thailand. METHODS: Multilingual demographic and KAP surveys were completed by 197 Thai, 119 Myanmar, and 176 Cambodian adults residing in Thailand. Thalassemia awareness, socio-demographic predictors, and knowledge and attitude scores were compared between migrant and Thai subjects. Comprehensive thalassemia testing was performed for migrants. RESULTS: Migrants had extremely poor thalassemia awareness (4.1%) compared to Thai subjects (79.6%) and had lower thalassemia knowledge scores but similar attitude scores. Surveys identified differing sociodemographic factors predicting awareness in Thai and migrant subjects, as well as key misconceptions likely to hinder thalassemia screening uptake. Nearly all migrants consented to thalassemia testing. We identified abnormal hemoglobin profiles in 52.7% of migrants and a higher projected rate of severe thalassemia births in migrants. CONCLUSIONS: The high burden of thalassemia and tremendous knowledge gap in migrants needs urgent attention. Thalassemia screening was feasible and acceptable in our migrant population. Sociocultural and structural barriers merit further attention when designing thalassemia screening and prevention policies for migrants in Thailand and globally.


Asunto(s)
Migrantes , Adulto , Pueblo Asiatico , Estudios Transversales , Estudios de Factibilidad , Humanos , Mianmar , Tailandia
5.
Ann Hematol ; 99(1): 23-29, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31776727

RESUMEN

Hemoglobin (Hb) F has a modulatory effect on the clinical phenotype of ß-thalassemia disease. High expression of Hb F in Hb E-related disorders has been noted, but the mechanism is not well understood. We have examined the association of a novel SNP rs11759328 on ARHGAP 18 gene and other known modulators with a variability of Hb F in Hb E-related disorders. Genotyping of SNP rs11759328 (G/A) was performed based on high-resolution melting analysis. The rs11759328 (A allele) was shown to be significantly associated with Hb F levels (p < 0.05) in heterozygous and homozygous Hb E. High levels of Hb F in both heterozygous and homozygous Hb E were also found to be associated with SNPs in the study of other modifying genes including KLF 1 mutation, rs7482144 (Gγ-XmnI), rs4895441, rs9399137 of (HBS1L-MYB), and rs4671393 (BCL11A). Multivariate analysis showed that KLF1 mutation and SNP rs11759328 (GA) (ARHGAP18) modulated Hb F expression in heterozygous Hb E. For homozygous Hb E, this was found to be related to five modifying factors, i.e., KLF1 mutation, rs4895441 (GG), rs9399137 (CC), rs4671393 (AA), and rs4671393 (GA). These results indicate that a novel SNP rs11759328 is a genetically modifying factor associated with increased Hb F in Hb E disorder.


Asunto(s)
Hemoglobina Fetal/biosíntesis , Proteínas Activadoras de GTPasa/genética , Regulación de la Expresión Génica , Hemoglobinuria/genética , Mutación , Polimorfismo de Nucleótido Simple , Hemoglobina Fetal/genética , Proteínas Activadoras de GTPasa/metabolismo , Hemoglobina E/genética , Hemoglobina E/metabolismo , Hemoglobinuria/sangre , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Tailandia
6.
Amino Acids ; 52(6-7): 893-904, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32468185

RESUMEN

Hemoglobinopathies are examples of autosomal recessive disorders of human hemoglobin. Hemoglobin E (HbE) and Hemoglobin D Punjab (HbD Punjab) are two of the most common hemoglobin variants geographically spread across Asian continent. These two variants differ from normal human hemoglobin (HbA) at a single amino acid residue caused by the point mutation of ß globin gene. The presence of the mutated amino acid residue causes perturbation in the function of both variants. However, the structure-function correlation of these variants has not been established yet. In the present study, we analyzed the conformational changes associated with oxygenation of hemoglobin variants using hydrogen/deuterium exchange-based mass spectrometry of backbone amide hydrogens of α and ß globin chains in the tetrameric hemoglobin molecule. We also performed the functional assay of these variants using oxygen dissociation equilibrium curve. Compared to HbA, both variants showed reduced oxygen affinity, as reported earlier. The functional perturbations exhibited by these variants were correlated well with their structural alterations with respect to the reported changes in the residue level interactions upon oxygenation of normal hemoglobin, monitored through the hydrogen/deuterium exchange kinetics of several peptic peptides originated from the isotopically exchanged oxy and deoxy forms of HbE and HbD Punjab.


Asunto(s)
Hemoglobina E/química , Hemoglobina E/genética , Hemoglobinas Anormales/química , Hemoglobinas Anormales/genética , Mutación Puntual/genética , Humanos , Espectrometría de Masas de Intercambio de Hidrógeno-Deuterio/métodos , Oxígeno/análisis , Oxihemoglobinas/análisis
7.
Mikrochim Acta ; 187(4): 238, 2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32189135

RESUMEN

A simple probe pair was designed for the detection of hemoglobin E (HbE) genotype, a single-point mutation that leads to abnormal red blood cells commonly found in South East Asia. The key to differentiation is the use of a conformationally constrained peptide nucleic acid (PNA) that was immobilized on carboxymethylcellulose-modified paper. This was then used for target DNA binding and visualization by an enzyme-catalyzed pigmentation. The biotinylated target DNA bound to the immobilized probe was visually detected via alkaline phosphatase-linked streptavidin. This enzyme conjugate catalyzed the dephosphorylation of the substrate 5-bromo-4-chloro-3-indolyl phosphate, leading to a series of reactions that generate an intense, dark blue pigment. The test was validated with 100 DNA samples, which shows good discrimination among different genotypes (normal, HbE, and heterozygous) with 100% accuracy when optimal conditions of analysis were applied. The method does not require temperature control and can be performed at ambient temperature. This is an attractive feature for diagnosis in primary care, which accounts for a large part of affected population. Graphical abstract Schematic representation of a paper-based sensor for the detection of the gene Hemoglobin E. The interaction between an immobilized peptide nucleic acid and a DNA target leads to enzymatic pigmentation, allowing simple visual readout with up to 100% accuracy.


Asunto(s)
Colorimetría/métodos , Genotipo , Sondas de Ácido Nucleico/química , Ácidos Nucleicos de Péptidos , Talasemia/genética , Biotinilación , Carboximetilcelulosa de Sodio , ADN/metabolismo , Humanos , Sondas de Ácido Nucleico/metabolismo , Pigmentación
8.
J Infect Dis ; 220(11): 1750-1760, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31549159

RESUMEN

BACKGROUND: Hemoglobin (Hb) data are limited in Southeast Asian glucose-6-phosphate dehydrogenase (G6PD) deficient (G6PD-) patients treated weekly with the World Health Organization-recommended primaquine regimen (ie, 0.75 mg/kg/week for 8 weeks [PQ 0.75]). METHODS: We treated Cambodians who had acute Plasmodium vivax infection with PQ0.75 and a 3-day course of dihydroartemisinin/piperaquine and determined the Hb level, reticulocyte count, G6PD genotype, and Hb type. RESULTS: Seventy-five patients (male sex, 63) aged 5-63 years (median, 24 years) were enrolled. Eighteen were G6PD deficient (including 17 with G6PD Viangchan) and 57 were not G6PD deficient; 26 had HbE (of whom 25 were heterozygous), and 6 had α-/ß-thalassemia. Mean Hb concentrations at baseline (ie, day 0) were similar between G6PD deficient and G6PD normal patients (12.9 g/dL [range, 9‒16.3 g/dL] and 13.26 g/dL [range, 9.6‒16 g/dL], respectively; P = .46). G6PD deficiency (P = <.001), higher Hb concentration at baseline (P = <.001), higher parasitemia level at baseline (P = .02), and thalassemia (P = .027) influenced the initial decrease in Hb level, calculated as the nadir level minus the baseline level (range, -5.8-0 g/dL; mean, -1.88 g/dL). By day 14, the mean difference from the day 7 level (calculated as the day 14 level minus the day 7 level) was 0.03 g/dL (range, -0.25‒0.32 g/dL). Reticulocyte counts decreased from days 1 to 3, peaking on day 7 (in the G6PD normal group) and day 14 (in the G6PD deficient group); reticulocytemia at baseline (P = .001), G6PD deficiency (P = <.001), and female sex (P = .034) correlated with higher counts. One symptomatic, G6PD-deficient, anemic male patient was transfused on day 4. CONCLUSIONS: The first PQ0.75 exposure was associated with the greatest decrease in Hb level and 1 blood transfusion, followed by clinically insignificant decreases in Hb levels. PQ0.75 requires monitoring during the week after treatment. Safer antirelapse regimens are needed in Southeast Asia. CLINICAL TRIALS REGISTRATION: ACTRN12613000003774.


Asunto(s)
Antimaláricos/administración & dosificación , Quimioprevención/métodos , Deficiencia de Glucosafosfato Deshidrogenasa , Hemólisis , Malaria Vivax/tratamiento farmacológico , Primaquina/administración & dosificación , Prevención Secundaria/métodos , Adolescente , Adulto , Antimaláricos/efectos adversos , Pueblo Asiatico , Quimioprevención/efectos adversos , Niño , Preescolar , Femenino , Glucosafosfato Deshidrogenasa , Hemoglobinas/análisis , Humanos , Masculino , Persona de Mediana Edad , Primaquina/efectos adversos , Recuento de Reticulocitos , Adulto Joven
9.
Pediatr Hematol Oncol ; 36(6): 394-398, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31424305

RESUMEN

Hemoglobin Köln, is the most common unstable hemoglobin variant worldwide, yet has only rarely been reported in Indians. Herein we report a case of coinheritance of Hb Köln and Hb E, which to the best of our knowledge has not been reported in the literature so far. The patient presented with mild symptoms of hemolysis with no previous history of blood transfusions.


Asunto(s)
Hemoglobina E/genética , Hemoglobinas Anormales/genética , Preescolar , Humanos , India , Masculino
10.
J Postgrad Med ; 64(4): 240-242, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29943740

RESUMEN

Moyamoya disease is an idiopathic, nonatherosclerotic, noninflammatory, chronic progressive cerebrovascular disease characterized by bilateral stenosis or occlusion of the arteries around the circle of Willis, typically the supraclinoid internal carotid arteries, followed by extensive collateralization, which are prone to thrombosis, aneurysm, and hemorrhage. Secondary moyamoya phenomenon or moyamoya syndrome (MMS) occurs in a wide range of clinical scenarios including prothrombotic states such as sickle cell anemia, but the association with other hemoglobinopathies is less frequently observed. We describe a case of a 25-year-old female with hemoglobin E-beta thalassemia who had a rare presentation of MMS in the form of choreoathetoid movements in the left upper and lower extremities. We describe this association, primarily to emphasize thalassemia as an extremely rare but a potential etiology of MMS. Since MMS is a progressive disease, it is important to diagnose and initiate treatment to prevent worsening of the disease and recurrence of stroke.


Asunto(s)
Hemoglobina E , Enfermedad de Moyamoya/etiología , Talasemia beta/complicaciones , Adulto , Femenino , Humanos
11.
Blood Cells Mol Dis ; 59: 85-91, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27282573

RESUMEN

Hemoglobin E is the most common Hb variant found in South East Asia. Variation of Hb F expression in Hb E syndrome is associated with several genetic modifiers. We report several single nucleotide polymorphisms (SNPs), including nine known and five novel mutations of the Krüppel-like factor 1 (KLF1; an erythroid specific transcription factor) gene and determine their associations with phenotypic expression of Hb F in Hb E disorders. KLF1 mutations were examined using high resolution melting (HRM) assay and DNA sequencing in 575 homozygous Hb E, 278 heterozygous Hb E and 100 normal subjects. Fourteen mutations were mostly observed in subjects with elevated Hb F, including nine known mutations (G176AfsX179, T334R, R238H, -154 (C>T), A298P, S270W, R301H, -148 (G>A) and G335R and five novel mutations (Q217X, Q223X, Y290_S293del, K307N, and M358I). None of them, but the -148 (G>A), were observed in normal controls to have Hb F <1%. Combined KLF1 mutations with other SNPs including (G)γ-XmnI, BCL11A and HBS1L-MYB were associated with higher Hb F levels. KLF1 is therefore an important genetic factor associated with increased Hb F and in combination with other modifying factors could explain the phenotypic variation of Hb F expression in this common hemoglobinopathy.


Asunto(s)
Hemoglobina Fetal/análisis , Hemoglobina E , Hemoglobinopatías/genética , Factores de Transcripción de Tipo Kruppel/genética , Mutación , Estudios de Casos y Controles , Hemoglobina E/genética , Heterocigoto , Homocigoto , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
12.
Matern Child Health J ; 20(11): 2367-2371, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27456306

RESUMEN

Background Homozygous hemoglobin E (HbE) disease is common, especially in Southeast Asia where the prevalence may be as high as nearly 1 % of pregnancies and it is usually associated with mild anemia. Nevertheless, the effects of the disease on pregnancy outcomes have never been explored. Objective To compare the obstetric adverse outcomes between singleton pregnancies complicated with HbE disease and normal controls. Patients and Methods A retrospective cohort study was undertaken by assessment of the database of maternal-fetal medicine units, Chiang Mai University, Thailand, from January 2000 to December 2014 to search for the records of pregnant women complicated by the disease. The records of low risk pregnancies were randomly selected as a control group with a ratio of 10:1. Pregnancies with underlying medical diseases or fetal abnormalities as well as those with no complete data were excluded. Result During the study period, 78 women with homozygous HbE disease (study group) and 780 normal controls were recruited. Most baseline characteristics of the two groups were similar. The mean birth weight was significantly lower in the study group (2683 ± 627 vs 2925 ± 623 g, P = 0.001).The prevalence of fetal growth restriction was also significantly higher in the study group (13.2 vs 6.7 %, P = 0.040, relative risk 1.96; 95 % CI 1.04-3.69), whereas the rates of other outcomes such as preterm birth were comparable. Conclusion for Practice Homozygous HbE disease does not increase risk of common adverse pregnancy outcomes, but it significantly increases risk of fetal growth restriction, resulting in significantly lower mean birth weight.


Asunto(s)
Hemoglobina E , Complicaciones Hematológicas del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Talasemia beta/complicaciones , Adulto , Estudios de Casos y Controles , Femenino , Retardo del Crecimiento Fetal/epidemiología , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Embarazo , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/etiología , Prevalencia , Estudios Retrospectivos , Tailandia/epidemiología , Talasemia beta/epidemiología
13.
Korean J Parasitol ; 53(3): 265-70, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26174819

RESUMEN

Hemoglobinopathy and malaria are commonly found worldwide particularly in malaria endemic areas. Thalassemia, the alteration of globin chain synthesis, has been reported to confer resistance against malaria. The prevalence of thalassemia was investigated in 101 malaria patients with Plasmodium falciparum and Plasmodium vivax along the Thai-Myanmar border to examine protective effect of thalassemia against severe malaria. Hemoglobin typing was performed using low pressure liquid chromatography (LPLC) and α-thalassemia was confirmed by multiplex PCR. Five types of thalassemia were observed in malaria patients. The 2 major types of thalassemia were Hb E (18.8%) and α-thalassemia-2 (11.9%). There was no association between thalassemia hemoglobinopathy and malaria parasitemia, an indicator of malaria disease severity. Thalassemia had no significant association with P. vivax infection, but the parasitemia in patients with coexistence of P. vivax and thalassemia was about 2-3 times lower than those with coexistence of P. falciparum and thalassemia and malaria without thalassemia. Furthermore, the parasitemia of P. vivax in patients with coexistence of Hb E showed lower value than coexistence with other types of thalassemia and malaria without coexistence. Parasitemia, hemoglobin, and hematocrit values in patients with coexistence of thalassemia other than Hb E were significantly lower than those without coexistence of thalassemia. Furthermore, parasitemia with coexistence of Hb E were 2 times lower than those with coexistence of thalassemia other than Hb E. In conclusion, the results may, at least in part, support the protective effect of thalassemia on the development of hyperparasitemia and severe anemia in malaria patients.


Asunto(s)
Malaria Falciparum/genética , Malaria Vivax/genética , Talasemia/genética , Femenino , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Malaria Falciparum/sangre , Malaria Falciparum/complicaciones , Malaria Falciparum/parasitología , Malaria Vivax/sangre , Malaria Vivax/complicaciones , Malaria Vivax/parasitología , Masculino , Persona de Mediana Edad , Plasmodium falciparum/fisiología , Plasmodium vivax/fisiología , Tailandia/epidemiología , Talasemia/sangre , Talasemia/complicaciones , Talasemia/epidemiología
14.
Indian J Clin Biochem ; 30(2): 238-42, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25883436

RESUMEN

The present case report describes the molecular and proteomic based study of Hb variant HbE associated with ß(+) thalassemia IVS 1-1 G>T, in a juvenile diabetic patient. Given the ethnic origin and mobility of the variant hemoglobin at alkaline pH, HbE would be suspected. But hematologically and clinically abnormality being detected, HPLC and Electrophoresis not being able to characterize due to retention time and band being in region of HbA2, respectively, further characterization of hemoglobinopathy was made using MALDI and IVS 1-1 G>T being validated by reverse dot blot hybridization. Capillary electrophoresis was also employed in order to separate HbE and HbA2 bands. This case report being first of its kind, wherein a HbE/ß(+) thalassemia has been characterized using multiple techniques.

15.
J Med Case Rep ; 18(1): 279, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38877536

RESUMEN

BACKGROUND: Glycated hemoglobin is a well-known marker for evaluating long-term glycemic control. However, the accuracy of glycated hemoglobin measurement can be affected by the presence of hemoglobin variants, which makes the determination and interpretation of glycated hemoglobin values in terms of glycemic control not only difficult but also misleading. Here we present the first ever case of a patient with type 2 diabetes with hemoglobin E from Nepal, diagnosed incidentally because of spurious glycated hemoglobin levels. CASE PRESENTATION: A 45-year-old Hindu Mongolian female with a history of type 2 diabetes for around 9 years but not very compliant with follow-ups was referred to our facility for plasma fasting and postprandial blood glucose levels and glycated hemoglobin. Fasting and postprandial blood sugars were found to be high. A consistent very low glycated hemoglobin by two different high-performance liquid chromatography (HPLC) methods compelled us to call the patient for a detailed clinical history and for the records of investigations done in the past. The patient has been a known case of type 2 diabetes for around 9 years and presented irregularly for follow-up visits. Around 4 years ago, she presented to a healthcare facility with fatigue, severe headaches, pain in the abdomen, discomfort, and dizziness for a couple of months, where she was shown to have high blood glucose. She was referred to a tertiary-level hospital in Kathmandu, where she was prescribed metformin 500 mg once daily (OD). Due to her abnormal hemoglobin A1c reports, she was then sent to the National Public Health Laboratory for repeat investigations. Her blood and urine investigations were sent. Complete blood count findings revealed high red blood cell and white blood cell counts, a low mean corpuscular volume, and a high red cell distribution width-coefficient of variation. Other parameters, including serum electrolytes, renal function tests, liver function tests, and urine routine examinations, were within normal limits. A peripheral blood smear revealed microcytic hypochromic red cells with some target cells. Hemoglobin electrophoresis showed a very high percentage of hemoglobin E, a very low percentage of hemoglobin A2, and normal proportions of hemoglobin A and hemoglobin F. A diagnosis of homozygous hemoglobin E was made, and family screening was advised. CONCLUSIONS: Clinicians should be aware of the limitations of glycated hemoglobin estimation by ion exchange high-performance liquid chromatography in patients with hemoglobin E and other hemoglobin variants. If the clinical impression and glycated hemoglobin test results do not match, glycated hemoglobin values should be determined with a second method based on a different principle, and glycemic status should be confirmed through alternative investigations, preferably those that are not influenced by the presence of hemoglobin variants (for example, boronate affinity chromatography, fructosamine test, glycated albumin test, the oral glucose tolerance test, continuous glucose monitoring, etc.). Consistent or even doubtful results should also raise the suspicion of a hemoglobin variant, which should be confirmed through further evaluation and investigations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hemoglobina Glucada , Hemoglobinas Anormales , Hallazgos Incidentales , Humanos , Femenino , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/sangre , Persona de Mediana Edad , Hemoglobina Glucada/análisis , Hemoglobinas Anormales/genética , Hemoglobinas Anormales/análisis , Glucemia/metabolismo , Hipoglucemiantes/uso terapéutico
16.
Clin Chim Acta ; 561: 119830, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38914363

RESUMEN

BACKGROUND AND AIMS: To update the molecular characteristics of α-thalassemia in northeast Thailand, the molecular basis and genetic interactions of Hb H disease were examined in a large cohort of patients. MATERIALS AND METHODS: A study was done on 1,170 subjects with Hb H disease and various genetic interactions encountered during 2009-2023. Hb and DNA analyses were carried out. RESULTS: As many as 40 genotypes with several known, previously undescribed, and novel mutations were observed. These included 698 subjects (59.8 %) of Hb H disease, 357 (30.6 %) with EABart's disease, 63 (5.4 %) with EEBart's disease, 18 (1.7 %) with abnormal Hbs, 17 (1.5 %) with ß-thalassemia, and 4 (0.4 %) with EFBart's or EFABart's disease. The molecular basis of 13 subjects (1.1 %) remains unknown. The α0-thalassemia included --SEA (n = 1,139, 97.4 %) and --THAI (n = 21, 1.8 %). Two rare mutations were identified in 3 subjects (0.3 %) with --SA and --CR deletions. For α+-thalassemia, -α3.7 kb del (n = 626, 53.5 %), Hb Constant Spring (n = 415, 35.5 %), -α4.2 kb del (n = 44, 3.8 %), Hb Paksé (n = 36, 3.1 %), and Hb Q-Thailand (n = 19, 1.6 %), were detected. Ten rarer α+-thalassemia were identified, including a novel mutation, namely the Hb Chumphae (HBA2:c.32T>A). The Hb H-Lansing-Ramathibodi, Hb H-Jax, and Hb H-Chumphae are hitherto undescribed in this region. PCR-based diagnostic methods for these α-thalassemia defects were described. CONCLUSIONS: This study confirms the diverse heterogeneity and genetic interactions causing Hb H disease in northeast Thailand. The results should prove useful for laboratory diagnosis and genetic counseling of this genetic disorder in the region.


Asunto(s)
Mutación , Talasemia alfa , Humanos , Talasemia alfa/genética , Talasemia alfa/diagnóstico , Tailandia , Estudios de Cohortes , Masculino , Femenino , Hemoglobina H/genética , Genotipo , Adulto , Adolescente
17.
Int J Gynaecol Obstet ; 166(1): 360-367, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38234105

RESUMEN

OBJECTIVE: To compare obstetric outcomes between women with ß-thalassemia/hemoglobin E (ß-thal/HbE) disease and those of low-risk pregnancies, and also between the two subgroups, ß-thal0/HbE and ß-thal+/HbE disease. METHODS: A retrospective cohort study was undertaken on pregnant women with ß-thal/HbE disease and low-risk pregnancies, which were randomly selected with a case-to-control ratio of 1:10. RESULTS: Pregnancies with ß-thal/HbE disease were identified in 0.19% of 59 152 pregnancies, including 104 women in the study group and 1040 women in the control group. The mean gestational age and mean birth weight were significantly lower in the study group. The prevalence of fetal growth restriction, preterm birth and low birth weight were significantly increased in the study group based on both univariate and multivariate analysis. The impacts were more striking in the ß-thal0/HbE subgroup than in the ß-thal+/HbE subgroup. The cesarean rate was significantly higher in the study group. No maternal death or serious complication was found in this cohort. CONCLUSION: Based on this cohort, the largest ever published, ß-thal/HbE disease is significantly associated with increased incidence of fetal growth restriction, preterm birth and low birth weight. The impacts were more pronounced in the ß-thal0/HbE subgroup. Pregnancy may be relatively safer for women with ß-thal/HbE disease.


Asunto(s)
Retardo del Crecimiento Fetal , Hemoglobina E , Recién Nacido de Bajo Peso , Resultado del Embarazo , Nacimiento Prematuro , Talasemia beta , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Talasemia beta/epidemiología , Talasemia beta/complicaciones , Adulto , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Recién Nacido , Retardo del Crecimiento Fetal/epidemiología , Complicaciones Hematológicas del Embarazo/epidemiología , Estudios de Casos y Controles , Edad Gestacional , Cesárea/estadística & datos numéricos , Peso al Nacer , Adulto Joven
18.
Lab Med ; 55(4): 528-533, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38253465

RESUMEN

We present 3 cases of discordant results from screening hemoglobin A1c (HbA1c) measured by ion-exchange high-performance liquid chromatography (HPLC) all due to various forms of interference and flagged by the instrument as "suspected hemoglobin E (HbE)." The first case was due to a rare hemoglobin variant, later confirmed to be hemoglobin Hoshida, the second due to "true" heterozygous HbE, and the third a result of analytical artifact causing splitting of the HbA1c peak without an underlying variant hemoglobin. We examine the similarities in these cases along with the laboratory work-up to classify each cause of interference to demonstrate the wide array of potential causes for the suspected HbE flag and why it warrants proper work-up. Because there is no standardized method of reporting out hemoglobin variant interference in HbA1c measurement, we discuss our laboratory's process of investigating discordant HbA1c measurements and reporting results in cases with variant interference as 1 possible model to follow, along with discussing the associated laboratory, ethical, and clinical considerations. We also examine the structure of hemoglobin Hoshida, HbE, and conduct a brief literature review of previous reports.


Asunto(s)
Hemoglobina Glucada , Hemoglobina E , Humanos , Hemoglobina Glucada/análisis , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Hemoglobina E/análisis , Hemoglobina E/genética , Masculino , Femenino , Persona de Mediana Edad , Adulto
19.
Indian J Hum Genet ; 19(3): 279-81, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24339538

RESUMEN

Hemoglobin E (Hb E) disorder is an important kind of hemoglobinopathy. It can be seen around the world with the highest prevalence in Southeast Asia. The screening for this disorder becomes the public health policies in many countries. The screening can be performed in several population groups. The newborn screening program for Hb E disorder is an important issue in pediatric genetics. In this brief review, the author discusses on important laboratory tests for screening for Hb E disorder in newborn.

20.
Int J Surg Case Rep ; 110: 108645, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37597431

RESUMEN

INTRODUCTION: Beta thalassemia (ß-thalassemia) in pregnant women increases the risk of obstetric problems such as premature birth and low birth weight, so caution is needed in its management; these cases are usually asymptomatic. PRESENTATION OF CASE: A pregnant Indonesian female (gestational age of 36 weeks), 21 years old, complained of general weakness. The patient experienced anemia several times during this pregnancy and received several blood transfusions. Her parents also have ß-thalassemia. A physical examination of the patient showed pale conjunctiva and slight icteric sclera. Laboratory examination showed abnormal included hemoglobin (Hb) of 6.7 g/dL, hematocrit of 207 %, mean corpuscular volume (MCV) of 60.1 fL, mean corpuscular hemoglobin (MCH) of 19.3 pg, mean corpuscular hemoglobin concentration (MCHC) of 32.1 g/dL, albumin of 3.06 g/dL, direct bilirubin of 0.75 mg/dL, and total bilirubin of 1.78 mg/dL. Peripheral blood smear examination showed ß-thalassemia. She received a high-calorie and protein diet with extra eggwhite of 2100 kcal/day, leukodepleted packed red blood cell (LD-PRBC) transfusion of 2 × 250 cc/day, folic acid of 3 × 1 mg/day, and methylprednisolone of 3 × 62.5 mg/day. The patient gave birth to a baby girl spontaneously. She received methylprednisolone of 3 × 16 mg with tapering off every week and folic acid of 3 × 1 mg. The patient's prognosis showed improvement. DISCUSSION: Pregnancy weakens the immune system; therefore ß-thalassemia is frequently discovered during this time, and keeping the mother's Hb ≥10 g/dL prevents complications. CONCLUSION: Maintaining Hb ≥10 g/dL minimizes complications for mother and baby.

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