Pitfalls in the Diagnosis of β-Thalassemia Intermedia

We present case histories of three patients who had β-thalassemia (β-thal) trait with 'unusual severity' managed as β-thal intermedia (β-TI) where the basis of disease severity could not be explained with routine hematological and genetic investigations. The clinical diagnosis of 'thalassemia intermedia' was justifiable as they had a β-thal mutation and disease severity that did not fit in with either β-thal trait or with β-thal major (β-TM). As mutations of α, β, and γ genes could not explain the unusual severity of the disease, further analysis with next-generation sequencing (NGS) for red cell diseases was carried out, which led to the diagnosis of coexisting membranopathies. This case series highlights the inherent difficulty in the diagnosis of β-TI with certainty in some patients where the genetic basis is not clear-cut

A "One-Stop" Screening Protocol for Haemoglobinopathy Traits and Iron Deficiency in Sri Lanka.

The high frequencies of carriers of severe haemoglobinopathies and of iron deficiency in Southeast Asia require reliable and affordable tests to improve on current screening procedures. We evaluate a "one stop" approach using the THALCON dichlorophenolindophenol (DCIP) and one-tube osmotic fragility (OF) tests and measurement of Zinc Protoporphyrin (ZPP) to detect and distinguish HbE and β-thalassaemia traits from iron deficiency. We compare findings with current screening practice in Sri Lanka that relies on the identification of low mean red cell volume and/or mean red cell hemoglobin for this purpose. Between November 2017 and May 2018, we undertook a cross-sectional survey of secondary school students in Gampaha district, Sri Lanka. The THALCON-DCIP and OF tests were compared to capillary electrophoresis (CE), used as a gold standard to detect haemoglobinopathies. ZPP was measured in whole blood. Plasma ferritin and C-reactive protein (CRP) were measured in students with a raised ZPP concentration. We collected venous blood samples from 1,324/1,332 (99.4%) students. The median age of the students was 17 (IQR 16-18) years, all were Sinhalese and 814/1,324 (61.5%) were female. CE identified 3 students with HbE trait and 26 students with β-thalassaemia trait. The THALCON-DCIP test was positive only in the 3 students with HbE (sensitivity 100%, 95% CI 29.2-100.0; specificity 100%, 95% CI 99.7-100.0). The THALCON-OF test identified all 26 students with β-thalassaemia trait (sensitivity = 100%, 95% CI 86.8-100.0) and 287 students with a normal CE result (specificity = 77.9%; 95% CI 75.5-80.1). It was also positive in 2/3 (66.7%) students with HbE trait. Iron deficiency (ZPP > 70 μmol/mol heme) was present in 118/1,240 (9.5%) students with a normal hemoglobin genotype, all of whom had plasma ferritin <15 ng/ml and CRP <5 mg/L. This one-stop approach offers reliable and affordable population screening for both haemoglobinopathy traits and iron deficiency in resource-limited settings where these conditions are common and ensures that iron supplements are targeted only to those who require them. Further work is warranted to refine the OF test to reduce the number of false positive results

Oxidative status in the β-thalassemia syndromes in Sri Lanka; a cross-sectional survey.

In the β-thalassemias, oxidative stress, resulting from chronic hemolysis, globin chain imbalance, iron overload and depleted antioxidant defences, likely contributes to cell death, organ damage, anemia, hypoxia and inflammation. We assessed variations in these parameters in β-thalassemia syndromes in Sri Lanka. Between November 2017 and June 2018, we assessed children and adults attending two thalassemia centres in Sri Lanka: 59 patients with HbE β-thalassemia, 50 β-thalassemia major, 40 β-thalassemia intermedia and 13 HbS β-thalassemia. Median age was 26.0 years (IQR 15.3-38.8), 101 (62.3%) were female and 152 (93.8%) of Sinhalese ethnicity. Methemoglobin, plasma hemoglobin, heme and ferritin were measured as sources of oxidants; plasma total antioxidant capacity, haptoglobin, hemopexin and vitamins C and E assessed antioxidant status; plasma thiobarbituric acid reactive substances and 8-hydroxy-2'-deoxyguanosine assessed oxidative damage; hemoglobin, plasma erythropoietin and transferrin receptor assessed anemia and hypoxia and plasma interleukin-6 and C-reactive protein assessed inflammation. Fruit and vegetable intake was determined by dietary recall. Physical fitness was investigated using the six-minute walk test and measurement of handgrip strength. Oxidant sources were frequently increased and antioxidants depleted, with consequent oxidative damage, anemia, hypoxia and inflammation. Biomarkers were generally most abnormal in HbE β-thalassemia and least abnormal in β-thalassemia intermedia but also varied markedly between individuals with the same thalassemia syndrome. Oxidative stress and damage were also more severe in splenectomized patients and/or those receiving iron chelation therapy. Less than 15% of patients ate fresh fruits or raw vegetables frequently, and plasma vitamins C and E were deficient in 132/160 (82.5%) and 140/160 (87.5%) patients respectively. Overall, physical fitness was poor in all syndromes and was likely due to anemic hypoxia. Studies of antioxidant supplements to improve outcomes in patients with thalassemia should consider individual patient variation in oxidative status both between and within the thalassemia syndromes

Leg Ulcers: A Report in Patients with Hemoglobin E Beta Thalassemia and Review of the Literature in Severe Beta Thalassemia

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 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 two largest treatment centres 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 two centres, 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. DISCUSSION/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

Survival and complications in patients with haemoglobin E thalassaemia in Sri Lanka: a prospective, longitudinal cohort study

BACKGROUND Worldwide, haemoglobin E β-thalassaemia is the most common genotype of severe β-thalassaemia. The paucity of long-term data for this form of thalassaemia makes evidence-based management challenging. We did a long-term observational study to define factors associated with survival and complications in patients with haemoglobin E thalassaemia. METHODS In this prospective, longitudinal cohort study, we included all patients with haemoglobin E thalassaemia who attended the National Thalassaemia Centre in Kurunegala, Sri Lanka, between Jan 1, 1997, and Dec 31, 2001. Patients were assessed up to three times a year. Approaches to blood transfusions, splenectomy, and chelation therapy shifted during this period. Survival rates between groups were evaluated using Kaplan-Meier survival function estimate curves and Cox proportional hazards models were used to identify risk factors for mortality. FINDINGS 109 patients (54 [50%] male; 55 [50%] female) were recruited and followed up for a median of 18 years (IQR 14-20). Median age at recruitment was 13 years (range 8-21). 32 (29%) patients died during follow-up. Median survival in all patients was 49 years (95% CI 45-not reached). Median survival was worse among male patients (hazard ratio [HR] 2·51, 95% CI 1·16-5·43), patients with a history of serious infections (adjusted HR 8·49, 2·90-24·84), and those with higher estimated body iron burdens as estimated by serum ferritin concentration (adjusted HR 1·03, 1·01-1·06 per 100 units). Splenectomy, while not associated with statistically significant increases in the risks of death or serious infections, ultimately did not eliminate a requirement for scheduled transfusions in 42 (58%) of 73 patients. Haemoglobin concentration less than or equal to 4·5 g/dL (vs concentration >4·5 g/dL), serum ferritin concentration more than 1300 μg/L (vs concentration ≤1300 μg/L), and liver iron concentration more than 5 mg/g dry weight of liver (vs concentration ≤5 mg/g) were associated with poorer survival. INTERPRETATION Patients with haemoglobin E thalassaemia often had complications and shortened survival compared with that reported in high-resource countries for thalassaemia major and for thalassaemia intermedia not involving an allele for haemoglobin E. Approaches to management in this disorder remain uncertain and prospective studies should evaluate if altered transfusion regimens, with improved control of body iron, can improve survival. FUNDING Wellcome Trust, Medical Research Council, US March of Dimes, Anthony Cerami and Ann Dunne Foundation for World Health, and Hemoglobal

Extensive systemic thrombo-embolism including intra-cardiac thrombosis mimicking an atrial myxoma in a patient with beta thalassaemia major – a case report

Abstract Background Sepsis and thrombo-embolic disease are well known complications of thalassemia major. Intracardiac thrombi are however rare and can lead to diagnostic dilemmas. Case presentation We report the case of a 20-year-old female splenectomised thalassaemia major patient with severe iron overload, who presented with life threatening sepsis associated with a liver abscess. Discovery of a large oscillating intra cardiac lesion on 2D echocardiogram confirmed by Contrast Enhanced Computed Tomography (CECT) chest in the right atrium extending from the left hepatic vein through the inferior vena cava complicated the clinical course. After a prolonged Intensive Care Unit (ICU) stay supported with antibiotics and anticoagulation, she recovered with evidence of resolution of the intra cardiac thrombus. Conclusions Early recognition and prompt aggressive treatment of sepsis in patients with thalassemia is essential to prevent complications. Intracardiac thrombosis is a potentially treatable cause for an intra cardiac mass in patients with thalassemia major, which should not be missed

Body iron status of children and adolescents with transfusion dependent β-thalassaemia: trends of serum ferritin and associations of optimal body iron control

Abstract Objective This cross sectional study aims to describe the body iron status, trends of serum ferritin and associations of optimal body iron control in patients aged below 16 years with transfusion dependent β-thalassaemia attending Paediatric and Adolescent Thalassaemia Centres of the Colombo North Teaching Hospital of Sri Lanka. Results Out of 54 children, 51% were males and a majority were aged 11–16 years; 83% had β-thalassaemia major while 13% had HbE β-thalassaemia. Mean serum ferritin was 1778(± 1458) µg/l and 29% had optimal serum ferritin (below 1000 µg/l). Trend of mean serum ferritin over time showed gradual decline between 2011 and 2017 and longitudinal trend of individual patients at yearly intervals showed gradual rise until 5 years of age and plateauing thereafter. All except two patients were receiving iron chelator medication of which the most commonly used was oral deferasirox (92%). The most common iron-related complications were short stature (24.1%) and pubertal delay (42.8% of > 14 years). None of the patients had hypothyroidism, hypoparathyroidism or diabetes. Optimal serum ferritin levels were significantly associated with the diagnosis of thalassaemia at a later age (23.6 vs 9.0 months) and higher family income (OR-4.81;95%CI 1.17–19.67) however was not associated with the age of the patient or duration of transfusion

The Thal-index with the BTT prediction.exe to discriminate β-thalassaemia traits from other microcytic anaemias

Several attempts have been made previously to differentiate &beta;-thalassaemia trait (BTT) from other microcytic anaemias using formulae with red cell (RC) parameters. Presently available formulae have low sensitivity and specificity. We wanted to develop a more precise algorithm, which could be used in situations where the gold-standard test for thalassaemia diagnosis: the high performance liquid chromatography (HPLC) is not available. The study was carried out prospectively from November 2008 to March 2010 from randomly collected blood samples with a mean cell volume (MCV) of less than 80 fL. HbA2 measured by HPLC was used to diagnose BTT. We used Fishers stepwise linear discriminant function analysis to develop an algorithm with RC parameters. Calculated new index Thal-index was then subjected to receiver operating characteristic curve analysis to identify best cutoff to discriminate BTT from other microcytic blood films. Software was developed to predict the BTT status (BTT prediction.exe). New index, referred to as the Thal-index, was calculated using discriminant function analysis and is given as Thal-index=[(0.615xMCV) +(0.518xmean corpuscular hemoglobin)+ (0.446xred cell distribution width)]. A value of 59 for Thal-index has 90% sensitivity and 85% specificity for differentiating BTT from other microcytic anaemias. This showed better sensitivity and specificity compared to other formulae presently used (i.e., Mentzer in Eshani, et al.). Our study gives a better answer to set-up where HPLC is not available. Although this cannot replace HPLC, BTT prediction.exe is useful to predict instantly and is the first ever computer program available for this function.&nbsp;先前已利用含红细胞（RC）参数的公式做出若干尝试，以鉴别&beta;-地中海贫血（BTT）和其他小红细胞性贫血。目前可用公式的敏感度和特异度均低。我们想要开发更精确的算法，在地中海贫血诊断的金标准测试法（即高效液相色谱法（HPLC））无法使用的情况下使用。2008年11月至2010年3月期间，我们按照预期对随机采集的血液样本（平均细胞体积（MCV）低于80fL）进行了本项研究。经高效液相色谱法测定的HbA2用于诊断&beta;-地中海贫血。我们利用Fishers逐步线性判别函数分析法开发一种含有红细胞参数的算法。计算出的新指标（地中海贫血指标）通过受试者操作特征曲线分析来确定区分&beta;-地中海贫血和其他小红细胞血涂片的最佳捷径。开发软件预测&beta;-地中海贫血状态（BTT预测.exe）。利用判别函数分析法计算新指标（即地中海贫血指标），得出以下公式：地中海贫血指标 = [(0.615 x平均细胞体积) + (0.518 x 红细胞平均血红蛋白量) + (0.446 x 红细胞体积分布宽度)]。指标值为59的地中海贫血指标用于区分&beta;-地中海贫血和其他小红细胞性贫血时含90%敏感度和85%特异度。相较于目前使用的其他公式（即Mentzer in Eshani公式 等），这种公式具有更高的敏感度和特异度。本研究得出一个在高效液相色谱法无法使用的情况下使用的更好公式。尽管不能替代高效液相色谱法，但BTT预测.exe对于即时预测很有帮助，也是迄今为止对该功能有效的计算机程序。</p

Redesigning New Policy Options for Thalassemia Prevention in Sri Lanka

Sri Lanka, a country with 22 million people, has nearly 2000 thalassemia patients with severe thalassemia, two-thirds of whom have beta thalassemia major (TM). The current prevention program based on promoting “safe marriages”, which has been in existence for over 15 years, has failed to reduce thalassemia major births. We set about to examine the cost-effectiveness of novel policy options for thalassemia prevention in Sri Lanka. Methods: The current cost for treatment of a thalassemia major patient (USD 2602/yr) was compared against the cost per reduction of single birth with three novel strategies, namely intensifying the screening in the current five districts combined with an education program (policy option 1), a nationwide screening program (policy option 2), and antenatal screening combined with the termination of pregnancy (policy option 3). The incremental cost-effectiveness ratio (ICER) of the different strategies was calculated. Results: The status quo was considered to reduce one TM birth whilst the new policy options were able to reduce births by 14, 35, and 48, respectively. The costs incurred for the program for a year for status quo and the three novel programs were USD 104,788, 173,884, 781,372, and 904,186 respectively. Cost per prevention of a thalassemia major birth was USD 87,324, 12,420, 22,324, and 20,084, respectively. The lifetime cost per treatment of a thalassemia major patient was USD 34,653. Conclusions: Given the current legal restriction on termination of pregnancy for fetal indications, policy option 2, an island-wide screening with mass education, is the most cost-effective and will be expected to deliver a substantial reduction in new births

MOESM1 of Body iron status of children and adolescents with transfusion dependent β-thalassaemia: trends of serum ferritin and associations of optimal body iron control

Additional file 1: Table S1. Clinical and socio-demographic characteristics of the study population