Association of GDF15 levels with body mass index and endocrine status in ß-thalassaemia.

OBJECTIVE: GDF15 has emerged as a stress-induced hormone, acting on the brain to reduce food intake and body weight while affecting neuroendocrine function. Very high GDF15 levels are found in thalassaemia, where growth, energy balance and neuroendocrine function are impaired. We examined the relationships between GDF15 and anthropometric measures and endocrine status in ß-thalassaemia. DESIGN: Cross sectional study. PATIENTS: All ß-thalassaemia patients attending the thalassaemia unit of Colombo North Teaching Hospital for blood transfusions. MEASUREMENTS: Anthropometric data, appetite scores, circulating GDF15, IGF, thyroid and reproductive hormone levels in 103 ß-thalassaemia patients were obtained. RESULTS: GDF15 levels were markedly elevated in thalassaemia patients (24.2-fold with ß-thalassaemia major compared with healthy controls). Among patients with ß-thalassaemia major, the relationship between GDF15 and body mass index (BMI) was curvilinear with all individuals with GDF15 levels above 24,000 pg/mL having a BMI below 20 kg/m2 . After adjustment for BMI, age and Tanner stage, serum IGF1 concentrations correlated negatively with GDF15 in all thalassaemia patients (ß = -.027, p = .02). We found a significant positive relationship between GDF15 and gonadotropin (in both sexes) and testosterone (in males). CONCLUSIONS: GDF15 levels were markedly elevated in patients with ß-thalassaemia and its association with BMI is consistent with the known effect of GDF15 to reduce body weight. The inverse association between GDF15 with IGF1 levels may reflect a neuroendocrine impact of GDF15 or an indirect effect via impaired nutritional state. The positive association with testosterone in males and gonadotropins in both sexes, was surprising and should prompt further GDF15 studies on the hypothalamic pituitary gonadal axis.

Lysinuric protein intolerance presenting as pancytopenia and splenomegaly mimicking acute leukaemia: a case report.

BACKGROUND: Lysinuric protein intolerance is a rare inherited metabolic disease due to autosomal recessive mutations of the SLC7A7 gene. The affected patients commonly present with protein-rich food intolerance, failure to thrive, hepatosplenomegaly, muscle hypotonia and lung involvement due to impaired intestinal absorption and excessive urinary excretion of dibasic amino acids. Presentation with splenomegaly and cytopenia without other features has not been reported. Here we report a Sri Lankan girl with lysinuric protein intolerance presenting with pancytopenia and splenomegaly mimicking acute leukaemia. CASE PRESENTATION: Two years and six months old Sri Lankan girl presented with persistent pancytopenia following a viral illness. She was asymptomatic without vomiting, diarrhoea, abdominal pain or irritability. Physical examination revealed pallor and isolated firm splenomegaly of 2 cm. Growth parameters and other system examinations were normal. Full blood count revealed anaemia, leukopenia and thrombocytopenia. The blood picture showed a mixture of hypochromic microcytic and normochromic normocytic red cells with occasional pencil cells and macrocytes. Bone marrow examination was normal except for occasional megaloblasts; however, serum vitamin B12 and red blood cell folate were normal. The metabolic screen showed a high anion gap compensated metabolic acidosis, high lactate and ketosis. Genetic mutation analysis using whole exome sequencing revealed compound heterozygous variants of the SLC7A7 gene, confirming the diagnosis of lysinuric protein intolerance. CONCLUSION: We report a child with lysinuric protein intolerance presenting with pancytopenia and splenomegaly without other disease features. This case report adds to the heterogenic presentations of lysinuric protein intolerance, which is considered a multifaceted disease.

Tender cervical lymphadenitis as a herald of multi-system inflammatory syndrome in COVID-19 infection of children and adolescents: a report of two cases.

BACKGROUND: Post-COVID-19 multisystem inflammatory syndrome (MIS) has been increasingly recognized but fever with isolated tender cervical lymphadenitis as the initial presentation has been rarely reported. We present 2 female patients one a child and the other an adolescent. CASE PRESENTATION: Case 1 was a 13-year-old girl who presented with tender cervical lymphadenopathy and fever 3-weeks post-COVID-19, and then developed features of MIS 5 days later. Case 2, also female, was 18 years old. She had no history of COVID-19 infection or immunization but had a serologic diagnosis of COVID-19. She similarly presented with fever and tender cervical lymphadenopathy, and then progressed rapidly to develop features of MIS. Both patients responded well to treatment with immunosuppressants and intravenous immunoglobulin. CONCLUSION: Tender cervical lymphadenopathy could be the herald of multi-system inflammatory syndrome following COVID-19 infection among children and adolescents, which the clinicians must have a good suspicion about.

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 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.

Electronic screen device usage and screen time among preschool-attending children in a suburban area of Sri Lanka.

BACKGROUND: Excessive use of screen devices and screen time are increasing health problems in children. We aim to describe the electronic screen device usage and determine the factors associated with their use among preschool-attending children in a suburban population in Sri Lanka. METHODS: A cross-sectional study was conducted in a suburban Medical Officer of Health area of Sri Lanka from January to March 2020. All children aged between 36-59 months attending ten randomly selected preschools were recruited. Data were collected using a parent-administered questionnaire and analysed using binary logistic regression in SPSS. The prevalence of electronic device usage, the average time spent on each device, and factors associated with individual device usage were analysed. RESULTS: A total of 340 children (Male-48%; mean age-50.1 ± 6.9 months) were recruited. Electronic devices were used by 96% of children. The most common devices were the television (87%) and the smartphone (63%). Of the children who used electronic devices, 60% exceeded the recommended screen time limit of one hour per day, 21% used devices for more than two hours per day, and 51% commenced using devices by two years of age. The higher education level of the father was independently associated with the use of smartphones and laptops and daily screen time of more than one hour (p < 0.05 for all). Male sex and being the only child were significantly associated with the use of smartphones, whereas maternal employment was associated with the use of laptops (p < 0.05 for all). CONCLUSIONS: Electronic screen devices were used by 96% of preschool-attending children, and over 60% used them for more than the recommended daily upper limit of one hour. Higher paternal education, maternal employment and being the only child were significantly associated with electronic screen device use.

A rare co-occurrence of duchenne muscular dystrophy, congenital adrenal hypoplasia and glycerol kinase deficiency due to Xp21 contiguous gene deletion syndrome: case report.

BACKGROUND: Contiguous gene deletion syndromes are rare genomic disorders caused by deletion of large segments of DNA resulting in co-occurrence of apparently unrelated multiple clinical phenotypes. We report a boy with contiguous gene deletion involving Xp21 genomic location. CASE PRESENTATION: A Sri Lankan boy with developmental delay and failure to thrive first presented at three years of age with hypovolaemia, hyperpigmentation and drowsiness. Investigations done at that time revealed hypoglycaemia, hyponatraemia, hyperkalaemia, low cortisol, low aldosterone, high ACTH and low 17-hydroxyprogesterone. He was diagnosed to have primary adrenal insufficiency. During follow-up at five years, he was noted to have progressive difficulty in walking, waddling gait, hypotonia, calf hypertrophy and positive Gower's sign. His creatine kinase was very high, and the electromyogram showed myopathy. Genetic analysis revealed hemizygous deletion involving the final 35 exons of the dystrophin gene confirming the diagnosis of Duchenne muscular dystrophy. Further investigations revealed pseudohypertriglyceridemia, large glycerol peak on urine organic acid analysis and hemizygous deletion of the glycerol kinase gene confirming glycerol kinase deficiency. Based on the presence of Duchenne muscular dystrophy, glycerol kinase deficiency and probable congenital adrenal hypoplasia along with genetic confirmation of deletions involving dystrophin and glycerol kinase genes, the diagnosis of Xp21 contiguous gene deletion syndrome was made. CONCLUSIONS: We report a child with contiguous gene deletion syndrome who was initially diagnosed as having isolated primary adrenal insufficiency probably due to congenital adrenal hypoplasia. Later he was confirmed to have Duchenne muscular dystrophy and glycerol kinase deficiency, as well. This case report highlights the importance of pre-emptive evaluation and identification of genetic defects when patients present with seemingly unrelated diseases that could aid in accurate diagnoses of contiguous gene deletion syndromes.

A child with Imerslund-Gräsbeck syndrome concealed by co-existing α-thalassaemia presenting with subacute combined degeneration of the spinal cord: a case report.

BACKGROUND: Imerslund-Gräsbeck syndrome is a rare genetic disease characterised by vitamin B12 deficiency and proteinuria. CASE PRESENTATION: A 4-year old Sri Lankan boy presented with gradually worsening difficulty in walking for two weeks duration. He was previously diagnosed and managed as having non-transfusion-dependent α-thalassaemia based on the presence of hypochromic microcytic anaemia, haemoglobin H inclusion bodies in the blood film and compound heterozygous α-thalassaemia genotype with a gene deletion. However, his transfusion requirement increased over the past three months and he gradually lost his motor developmental milestones during two weeks before admission. The neurological examination revealed generalised hypotonia, exaggerated knee jerks and extensor plantar response. His complete blood count showed pancytopenia, and bone marrow biopsy revealed megaloblastic changes. Serum vitamin B12 and red blood cell folate levels were low. MRI revealed sub-acute combined degeneration of the spinal cord with characteristic 'inverted V sign'. Urine analysis showed non-nephrotic range proteinuria. The diagnosis of Imerslund-Gräsbeck syndrome was made due to the presence of non-nutritional vitamin B12 deficiency and asymptomatic proteinuria. He showed a rapid haematological and neurological improvement to intramuscular hydroxocobalamin. CONCLUSIONS: This case report presents a rare occurrence of severe vitamin B12 deficiency due to Imerslund-Gräsbeck syndrome masked by co-existent α-thalassaemia, resulting in serious consequences. It highlights the need for a high index of suspicion in evaluating children with severe anaemia, especially in the presence of mixed pathologies.

Marriage patterns in Sri Lanka and the prevalence of parental consanguinity in patients with ß-thalassaemia: a cross-sectional descriptive analysis.

Consanguineous marriages potentially play an important role in the transmission of ß-thalassaemia in many communities. This study aimed to determine the rate and socio-demographic associations of consanguineous marriages and to assess the influence on the prevalence of ß-thalassaemia in Sri Lanka. Three marriage registrars from each district of Sri Lanka were randomly selected to prospectively collect data on all couples who registered their marriage during a 6-month period starting 1st July 2009. Separately, the parents of patients with ß-thalassaemia were interviewed to identify consanguinity. A total of 5255 marriages were recorded from 22 districts. The average age at marriage was 27.3 (±6.1) years for males and 24.1 (±5.7) years for females. A majority (71%) of marriages were 'love' marriages, except in the Moor community where 84% were 'arranged' marriages. Overall, the national consanguinity rate was 7.4%. It was significantly higher among ethnic Tamils (22.4%) compared with Sinhalese (3.8%) and Moors (3.2%) (p < 0.001). Consanguinity rates were also higher in 'arranged' as opposed to 'love' marriages (11.7% vs 5.6%, p < 0.001). In patients with ß-thalassaemia, the overall consanguinity rate was 14.5%; it was highest among Tamils (44%) and lowest among Sinhalese (12%). Parental consanguinity among patients with ß-thalassaemia was double the national average. Although consanguinity is not the major factor in the transmission of the disease in the country, emphasis should be given to this significant practice when conducting ß-thalassaemia prevention and awareness campaigns, especially in high-prevalence communities.

Microcytic anemia in children: parallel screening for iron deficiency and thalassemia provides a useful opportunity for thalassemia prevention in low- and middle-income countries.

Microcytic anemia in children is commonly attributed to iron deficiency without attempting to find the cause. Inadequate investigations to exclude hemoglobinopathies lead to missed opportunities for identification of thalassemia carriers. Here we aim to describe the relative contribution of iron deficiency and thalassemia to microcytic anemia in children. This hospital-based prospective study was conducted at the Colombo North Teaching Hospital, Ragama, Sri Lanka. All newly diagnosed patients with microcytic anemia were recruited and data were collected using an interviewer-administered questionnaire. Full blood count, blood film, serum ferritin, c-reactive protein, quantification of hemoglobin sub-types and α-globin genotype were performed using 4 ml of venous blood. A total of 104 children (Male- 60.5%) were recruited. Iron deficiency was the cause for anemia in 49% whilst 16% and 10% had α- and ß-thalassemia trait respectively. Seven (6.7%) children had co-existing iron deficiency and thalassemia trait while two coinherited α- and ß-thalassemia trait. Children with ß-thalassemia trait had significantly higher red cell count and lower mean corpuscular volume compared to children with iron deficiency. However, none of the red cell parameters were significantly different between children with α-thalassemia trait and iron deficiency. Iron deficiency contributes only to half of children with microcytic anemia; one-fourth had thalassemia trait. Co-existence of iron deficiency and thalassemia trait or co-inheritance of α- and ß-thalassemia trait were found in 9%. Parallel investigation of children with microcytic anemia to diagnose iron deficiency and thalassemia provides an opportunity to identify thalassemia carriers which is beneficial for thalassemia prevention.

Blood transfusion therapy for ß-thalassemia major and hemoglobin E ß-thalassemia: Adequacy, trends, and determinants in Sri Lanka.

BACKGROUND: Regular blood transfusion therapy still remains the cornerstone in the management of ß-thalassemia. Although recommendations are clear for patients with ß-thalassemia major, uniform transfusion guidelines are lacking for patients with hemoglobin E ß-thalassemia. In this study, we aim to describe the adequacy, trends, and determinants of blood transfusion therapy in a large cohort of pediatric patients with ß-thalassemia major and hemoglobin E ß-thalassemia. METHODS/PROCEDURE: This cross-sectional study was performed among all regularly transfused patents with ß-thalassemia aged 2 to 18 years attending three large thalassemia centers in Sri Lanka. Data were collected using an interviewer-administered questionnaire, perusal of clinical records, and physical examination of patients by trained doctors. RESULTS: A total of 328 patients (male 47%) were recruited; 83% had ß-thalassemia major, whereas 16% had hemoglobin E ß-thalassemia. Sixty-one percent of patients had low pretransfusion hemoglobin levels (< 9.0 g/dL) despite receiving high transfusion volumes (> 200 mL/kg/year) by a majority (56%). Median pretransfusion hemoglobin was significantly lower in patients with hemoglobin E ß-thalassemia compared with ß-thalassemia major (P < 0.001); however, there was no difference in requirement for high transfusion volumes over 200 mL/kg/year in both groups (P = 0.14). Hepatomegaly and splenomegaly were more common in hemoglobin E ß-thalassemia and were associated with lower pretransfusion hemoglobin. Transfusion requirements were higher among patients with hepatitis C and in those who are underweight. CONCLUSIONS: Over 60% of regularly transfused patients with ß-thalassemia have low pretransfusion hemoglobin levels despite receiving large transfusion volumes. Patients with hemoglobin E ß-thalassemia are undertransfused and specific recommendations should be developed to guide transfusions in these patients.

Health related quality of life among children with transfusion dependent ß-thalassaemia major and haemoglobin E ß-thalassaemia in Sri Lanka: a case control study.

BACKGROUND: Thalassaemia is a chronic disease without an effective cure in a majority. The clinical management has improved considerably during recent years; however, minimal attempts are made to up lift the quality of life among patients, especially in developing countries. Here we aim to describe and compare and to determine factors associated with health related quality of life among patients with transfusion dependent ß-thalassaemia major and haemoglobin E ß-thalassemia in Sri Lanka. METHODS: A case control study was conducted in the three largest thalassaemia centres of Sri Lanka. All patients with transfusion dependent ß-thalassaemia (ß-thalassaemia major and haemoglobin E ß-thalassaemia) aged 5-18 years were recruited as cases whilst a randomly selected group of children without chronic diseases were recruited as controls. Socio-demographic and clinical data were collected using an interviewer-administered questionnaire and health related quality of life was measured using the validated Paediatric Quality of Life Inventory Version 4.0. RESULTS: Two hundred and seventy one patients with transfusion dependent ß-thalassaemia (male-49.1%; mean age- 10.9 ± 3.6 years) and 254 controls (male-47.2%; mean age- 10.4 ± 3.5 years) were recruited. Mean health-related quality of life scores were significantly lower in patients compared to controls (72.9 vs. 91.5, p < 0.001). Of the patients, 224 (84%) had ß-thalassaemia major and 43 (16%) had haemoglobin E ß-thalassaemia. Quality of life scores in psychological health (p < 0.05), emotional functioning (p < 0.05) and social functioning (p < 0.05) were significantly lower in patients with haemoglobin E ß-thalassaemia compared to ß-thalassaemia major. Splenectomy (p < 0.05), short stature (p < 0.05), under nutrition (p < 0.05) and longer hospital stays (p < 0.05) were significantly associated with lower quality of life scores. CONCLUSIONS: Despite improvements in management, the quality of life among patients with ß-thalassaemia still remains low. This is more pronounced in the subset of patients with haemoglobin E ß-thalassaemia. Splenectomy, short stature, undernutrition and longer hospital stays were significantly associated with poor quality of life. It is timely, even in developing countries, to direct emphasis and to take appropriate steps to improve standards of living and quality of life of patients with ß-thalassaemia.

A child with Gradenigo syndrome presenting with meningism: a case report.

BACKGROUND: The symptoms of meningitis which include fever, headache, photophobia and irritability along with abducens nerve palsy pose a diagnostic dilemma requiring urgent attention. Here we report how such a dilemma was methodically and sequentially resolved using anatomical knowledge supported by neuroimaging and the eventual diagnosis of Gradenigo syndrome was made. CASE PRESENTATION: A 6-year-old previously healthy boy from Sri Lanka presented with high grade fever, headache, photophobia and left eye pain for 10 days and diplopia for 2 days duration. Neurological examination was unremarkable except for left sided abducens nerve palsy. He had high inflammatory markers and white blood cell count. A tentative differential diagnosis of acute bacterial meningitis complicated by cerebral oedema, acute hydrocephalus or cerebral abscess was made. However, non-contrast CT brain, cerebrospinal fluid analysis and electroencephalogram were normal leading to a diagnostic dilemma. MRI brain with contrast performed 3 days later due to limited resources revealed left mastoiditis extending to petrous temporal bone confirming Gradenigo syndrome. CONCLUSION: This case report highlights the importance of a thorough physical examination in children presenting with unrelated neurological symptoms and signs. Unilateral abducens nerve palsy raises the suspicion of increased intracranial pressure and neuroimaging is vital in diagnostic uncertainties. Gradenigo syndrome emphasises the importance of incorporating anatomical knowledge into clinical practice.

Chiari malformation type 1 presenting as unilateral progressive foot drop: a case report and review of literature.

BACKGROUND: Foot drop is a disabling clinical condition with multiplicity of causes, which requires detailed evaluation to identify the exact aetiology. Here, we report an extremely rare cause of foot drop in a child, which if not recognized early, could lead to multiple complications. CASE PRESENTATION: A 6-year-old girl presented with difficulty in walking and left sided foot droop for1-month duration. On examination she had reduced muscle power in dorsiflexors and plantar flexors and diminished knee and absent ankle jerk in the left side. Sensory loss was noted in L4 and L5 dermatomes on the left side. Superficial abdominal reflex was absent on the left side while preserved in the right. Nerve conduction and electromyography revealed nerve root or spinal cord cause for the foot drop. These results prompted ordering MRI spine and brain which revealed Chiari malformation type-1 with holocord syrinx extending from the cervicomedullary junction to conus medullaris. CONCLUSIONS: This case highlights the importance of considering broad differential diagnosis for foot drop and value of the complete neurological examination including superficial reflexes in arriving at a diagnosis. Prompt diagnosis helped to early neurosurgical referral and intervention which is an important prognostic factor.

α-Globin as a molecular target in the treatment of ß-thalassemia.

The thalassemias, together with sickle cell anemia and its variants, are the world's most common form of inherited anemia, and in economically undeveloped countries, they still account for tens of thousands of premature deaths every year. In developed countries, treatment of thalassemia is also still far from ideal, requiring lifelong transfusion or allogeneic bone marrow transplantation. Clinical and molecular genetic studies over the course of the last 50 years have demonstrated how coinheritance of modifier genes, which alter the balance of α-like and ß-like globin gene expression, may transform severe, transfusion-dependent thalassemia into relatively mild forms of anemia. Most attention has been paid to pathways that increase γ-globin expression, and hence the production of fetal hemoglobin. Here we review the evidence that reduction of α-globin expression may provide an equally plausible approach to ameliorating clinically severe forms of ß-thalassemia, and in particular, the very common subgroup of patients with hemoglobin E ß-thalassemia that makes up approximately half of all patients born each year with severe ß-thalassemia.

Human induced pluripotent stem cell derived erythroblasts can undergo definitive erythropoiesis and co-express gamma and beta globins.

Human induced pluripotent stem cells (hiPSCs), like embryonic stem cells, are under intense investigation for novel approaches to model disease and for regenerative therapies. Here, we describe the derivation and characterization of hiPSCs from a variety of sources and show that, irrespective of origin or method of reprogramming, hiPSCs can be differentiated on OP9 stroma towards a multi-lineage haemo-endothelial progenitor that can contribute to CD144(+) endothelium, CD235a(+) erythrocytes (myeloid lineage) and CD19(+) B lymphocytes (lymphoid lineage). Within the erythroblast lineage, we were able to demonstrate by single cell analysis (flow cytometry), that hiPSC-derived erythroblasts express alpha globin as previously described, and that a sub-population of these erythroblasts also express haemoglobin F (HbF), indicative of fetal definitive erythropoiesis. More notably however, we were able to demonstrate that a small sub-fraction of HbF positive erythroblasts co-expressed HbA in a highly heterogeneous manner, but analogous to cord blood-derived erythroblasts when cultured using similar methods. Moreover, the HbA expressing erythroblast population could be greatly enhanced (44·0 ± 6·04%) when a defined serum-free approach was employed to isolate a CD31(+) CD45(+) erythro-myeloid progenitor. These findings demonstrate that hiPSCs may represent a useful alternative to standard sources of erythrocytes (RBCs) for future applications in transfusion medicine.

Efficacy and safety of deferoxamine, deferasirox and deferiprone triple iron chelator combination therapy for transfusion-dependent ß-thalassaemia with very high iron overload: a protocol for randomised controlled clinical trial.

INTRODUCTION: Despite the improvement in medical management, many patients with transfusion-dependent ß-thalassaemia die prematurely due to transfusion-related iron overload. As per the current guidelines, the optimal chelation of iron cannot be achieved in many patients, even with two iron chelators at their maximum therapeutic doses. Here, we evaluate the efficacy and safety of triple combination treatment with deferoxamine, deferasirox and deferiprone over dual combination of deferoxamine and deferasirox on iron chelation in patients with transfusion-dependent ß-thalassaemia with very high iron overload. METHODS AND ANALYSIS: This is a single-centre, open-label, randomised, controlled clinical trial conducted at the Adult and Adolescent Thalassaemia Centre of Colombo North Teaching Hospital, Ragama, Sri Lanka. Patients with haematologically and genetically confirmed transfusion-dependent ß-thalassaemia are enrolled and randomised into intervention or control groups. The intervention arm will receive a combination of oral deferasirox, oral deferiprone and subcutaneous deferoxamine for 6 months. The control arm will receive the combination of oral deferasirox and subcutaneous deferoxamine for 6 months. Reduction in iron overload, as measured by a reduction in the serum ferritin after completion of the treatment, will be the primary outcome measure. Reduction in liver and cardiac iron content as measured by T2* MRI and the side effect profile of trial medications are the secondary outcome measures. ETHICS AND DISSEMINATION: Ethical approval for the study has been obtained from the Ethics Committee of the Faculty of Medicine, University of Kelaniya (Ref. P/06/02/2023). The trial results will be disseminated in scientific publications in reputed journals. TRIAL REGISTRATION NUMBER: The trial is registered in the Sri Lanka Clinical Trials Registry (Ref: SLCTR/2023/010).

Direct correction of haemoglobin E ß-thalassaemia using base editors.

Haemoglobin E (HbE) ß-thalassaemia causes approximately 50% of all severe thalassaemia worldwide; equating to around 30,000 births per year. HbE ß-thalassaemia is due to a point mutation in codon 26 of the human HBB gene on one allele (GAG; glutamatic acid → AAG; lysine, E26K), and any mutation causing severe ß-thalassaemia on the other. When inherited together in compound heterozygosity these mutations can cause a severe thalassaemic phenotype. However, if only one allele is mutated individuals are carriers for the respective mutation and have an asymptomatic phenotype (ß-thalassaemia trait). Here we describe a base editing strategy which corrects the HbE mutation either to wildtype (WT) or a normal variant haemoglobin (E26G) known as Hb Aubenas and thereby recreates the asymptomatic trait phenotype. We have achieved editing efficiencies in excess of 90% in primary human CD34 + cells. We demonstrate editing of long-term repopulating haematopoietic stem cells (LT-HSCs) using serial xenotransplantation in NSG mice. We have profiled the off-target effects using a combination of circularization for in vitro reporting of cleavage effects by sequencing (CIRCLE-seq) and deep targeted capture and have developed machine-learning based methods to predict functional effects of candidate off-target mutations.

24 h Activity Guidelines in Children and Adolescents: A Prevalence Survey in Asia-Pacific Cities.

This study aimed to examine the prevalence of adherence to 24 h activity guidelines in children and adolescents from Asia-Pacific cities. In 1139 children aged 5-18 years, moderate-to-vigorous physical activity (MVPA), screen viewing time (SVT), sleep duration, child weight, height, sex, and age were parent-reported. Descriptive statistics were used to assess the number of guidelines met, and prevalence of adherence to activity guidelines by city and child sex. Prevalence of meeting all three 24 h activity guidelines was low across all countries (1.8-10.3%) (p < 0.05). Children from Thiruvananthapuram, India had the highest [10.3% (95% CI: 6.0-17.0)], while those from Tokyo, Japan had the lowest prevalence [1.8% (95% CI: 0.5-7.0)] of meeting all three guidelines. The highest prevalence of meeting individual MVPA, SVT and sleep guidelines was found in India [67.5% (95% CI: 58.8-75.1)], Kelaniya, Sri Lanka [63.2% (95% CI: 58.7-67.4)] and Kowloon, Hong Kong [59.4% (95% CI: 51.1-65.3)], respectively. Overall, a higher prevalence of boys met all three guidelines, compared to girls [5.9% (95% CI: 4.1-8.1) vs. 4.7% (3.1-6.6), p = 0.32]. The prevalence of adhering to all three activity guidelines was low in all five participating cities, with a higher proportion of boys meeting all guidelines.