Evaluation of an In-House Genetic Testing Method for Confirming Prader-Willi and Angelman Syndromes in Sri Lanka.

BACKGROUND: Prader-Willi syndrome (PWS, MIM 176,270) and Angelman syndrome (AS, MIM 105,830) are caused by imprinting defects of chromosome 15q11-13, with loss of maternal gene expression causing AS and paternal gene expression causing PWS. The diagnosis, once established in most cases by using a methylation-specific PCR test, enables appropriate therapeutic interventions and avoids the need for further investigations. Genetic testing for PWS/AS is limited in Sri Lanka (and in other low- and middle-income countries), mainly because parents are unable to pay for testing as these are not funded by the health service. METHODS: Ninety cases (46 female) with clinical features suggesting PWS (n = 37) and AS (n = 53), referred by a pediatric endocrinologist and a pediatric neurologist, were recruited. Clinical information and blood samples were obtained following informed consent. DNA was extracted and methylation-specific PCR (MS-PCR) was performed following bisulfite modification of DNA by using an in-house method and a kit. Results were validated using known positive controls. Parent-child trio DNA samples were used in cases with confirmed PWS and AS to determine if the disease was due to a deletion or uniparental disomy. The cost of the MS-PCR testing of the two modification methods and the microsatellite analysis was determined. RESULTS: Among the suspected PWS cases, 19/37 were positive, while 5/53 of the suspected AS cases were positive. The lower identification rate of AS is probably related to the overlap of clinical features of this condition with other disorders. The kit-based modification method was more reliable, less time-consuming, and cost-effective in our laboratory. CONCLUSIONS: The kit-based modification followed by MS-PCR described in this study enables more affordable genetic testing of suspected PWS/AS cases, and this is likely to improve patient care by targeting appropriate therapy for the affected cases. Parental genetic counselling is made possible regarding the low recurrence risk, especially where a deletion or uniparental disomy is confirmed. In MS-PCR, negative cases with a strong clinical suspicion of AS, UBE3A mutation testing is required. In addition, imprinting center mutation/deletion testing may also be needed in strongly clinically suspected, MS-PCR negative PWS and AS cases.

Pediatric diabetes care in Sri Lanka and Bangladesh: Reaching the community.

Diabetes is a major non-communicable disease with long-term complications. Over one million children and adolescents are affected with type 1 diabetes in the world. The number of children and adolescents with type 2 diabetes is also on the rise due to the increase incidence of childhood diabetes. South East Asian (SEA) contributes 184 100 children and adolescents with type 1 diabetes under the age of 20 years for this global health issue as at 2019. Countries of SEA region share same socio demographic, cultural, and economic challenges when it comes to holistic care of affected children. It is timely to discuss common concerns of these countries to give the best possible care for children affected with diabetes to minimize the burden of diabetes related complications, which would potentially affect the socioeconomic development of the respective countries.

Temporal Trends in Acute Adrenal Insufficiency Events in Children With Congenital Adrenal Hyperplasia During 2019-2022.

Background: It is unclear whether targeted monitoring of acute adrenal insufficiency (AI) related adverse events (AE) such as sick day episodes (SDEs) and hospitalization rate in congenital adrenal hyperplasia (CAH) is associated with a change in the occurrence of these events. Aim: Study temporal trends of AI related AE in the I-CAH Registry. Methods: In 2022, data on the occurrence of AI-related AE in children aged <18 years with 21-hydroxylase deficiency CAH were compared to data collected in 2019. Results: In 2022, a total of 513 children from 38 centers in 21 countries with a median of 8 children (range 1-58) per center had 2470 visits evaluated over a 3-year period (2019-2022). The median SDE per patient year in 2022 was 0 (0-2.5) compared to 0.3 (0-6) in 2019 (P = .01). Despite adjustment for age, CAH phenotype and duration of study period, a difference in SDE rate was still apparent between the 2 cohorts. Of the 38 centers in the 2022 cohort, 21 had also participated in 2019 and a reduction in SDE rate was noted in 13 (62%), an increase was noted in 3 (14%), and in 5 (24%) the rate remained the same. Of the 474 SDEs reported in the 2022 cohort, 103 (22%) led to hospitalization compared to 299 of 1099 SDEs (27%) in the 2019 cohort (P = .02). Conclusion: The I-CAH Registry can be used for targeted monitoring of important clinical benchmarks in CAH. However, changes in reported benchmarks need careful interpretation and longer-term monitoring.

Relationship between serum 25-hydroxyvitamin D and parathyroid hormone in the search for a biochemical definition of vitamin D deficiency in children.

BACKGROUND: Current guidelines use differing definitions of vitamin D deficiency based on serum 25-hydroxyvitamin D (25OHD) levels, which complicates clinical decision making on vitamin D doses used for the prevention and treatment. This study examined the natural relationship between serum 25OHD, parathyroid hormone (PTH), calcium, phosphate, and alkaline phosphatase. METHODS: Two-hundred and fourteen children routinely admitted without conditions affecting the natural relationship among metabolites, including 17 with radiologically confirmed vitamin D deficiency rickets, were studied. The frequency of abnormal bone metabolites was examined for different 25OHD thresholds. RESULTS: The best fitting intersection point where PTH levels increased was a 25OHD level of 34 nmol/l (R(2) = 0.454; 95% confidence interval: 27-41 nmol/l). Seventy-three and 86% of the children demonstrated some biochemical abnormality below 25OHD levels of 41 and 27 nmol/l, respectively. All patients with rickets had 25OHD levels < 34 nmol/l. The vast majority of children with abnormal bone metabolites had 25OHD levels < 34 nmol/l and PTH levels > 50 ng/l. CONCLUSION: Vitamin D deficiency, based on PTH elevation, was best defined by a 25OHD level of < 34 nmol/l. Because deficient calcium supply often coexists with vitamin D deficiency and both can independently cause nutritional rickets, a threshold for the skeletal effects of vitamin D should not be based purely on 25OHD levels.

An association of craniopharyngioma in Turner syndrome.

Turner syndrome (TS) (approximately 1:5,000 births) and craniopharyngioma (CP) (1:50,000 children) are both rare conditions. We present three cases of TS with CP, an association not previously described. Visual failure, poor growth or headache led to MRI diagnosis of CP. Whilst two had evidence of hypopituitarism at diagnosis of CP, they all developed hypopituitarism following surgical debulking. Two required radiotherapy due to regrowth. Whether CP and TS share a similar aetiology is unknown. Clinicians need to be aware of this association, and should perform urgent MRI scanning in TS patients with headache, visual impairment or clinical/biochemical evidence of hypopituitarism.

Acute postprandial gut hormone, leptin, glucose and insulin responses to resistant starch in obese children: a single blind crossover study.

INTRODUCTION: Resistant starch (RS) has beneficial effects on postprandial glucose metabolism in both animals and adults. Hitherto, there have been no studies in children of the acute metabolic and hormonal effects of RS-containing meals. OBJECTIVES: We aimed to compare serial plasma glucose, insulin, gut hormone, leptin profiles and satiety scores in obese children after meals containing variable amounts of RS. METHODS: This was a single blind, non-randomised, crossover study of 20 obese children aged 10-14 years old without comorbidities. Three test meals containing rice (M1), rice cooked with coconut oil (M2), rice cooked in coconut oil with lentils (M3) were given in sequence after a 12-hour fast . Blood samples were analysed for glucose (PG), insulin, leptin, glucagon-like polypeptide (GLP) 1, ghrelin and peptide YY (PYY) at appropriate times between 0 and 180 min. RESULTS: Meal M2 resulted in significantly lower postprandial glucose values compared with meal M1 (maximal incremental glucose, ∆Cmax, p<0.05; area under the curve, ∆AUC0-3, p<0.01) and meal M3 (maximal concentration, Cmax, p<0.01; ∆Cmax, p<0.001, and ∆AUC0-3p<0.01). M2 also produced lower insulin values compared with M1 (p<0.05). Postprandial ghrelin was significantly higher after M1 compared with M3 (p<0.05). PYY, GLP1 and median satiety scores were not significantly different between the three meals. CONCLUSION: This study shows that M2, the meal containing RS alone, induced beneficial effects on acute postprandial glucose, insulin and ghrelin concentrations in obese children without diabetes. Acute postprandial satiety scores were not significantly affected by the three meals. TRIAL REGISTRATION NUMBER: SLCTR/2020/007.

The prevalence of diabetes and thyroid related autoantibodies in Sri Lankan children with type 1 diabetes and their unaffected siblings - The utility of a new screening assay.

Background: There is limited information about diabetes and thyroid related autoantibodies in children with type 1 diabetes (T1D) or their siblings in Sri Lanka. Objectives: To assess in T1D children and their unaffected siblings the prevalence of autoantibodies to (1) glutamic acid decarboxylase (GADA), insulinoma associated antigen-2 (IA-2A) and zinc transporter 8 (ZnT8A) using 3 Screen ICA™ (3-Screen) and individual ELISA assays; (2) insulin (IAA); and (3) thyroid peroxidase (TPOA), thyroglobulin (TgA) and the TSH receptor (TSHRA). Methods: We selected - (a) consecutive T1D children, and (b) their unaffected siblings of both sexes, from the T1D Registry at Lady Ridgeway Hospital, Colombo. Results: The median age (IQR) of 235 T1D children and 252 unaffected siblings was 11 (8.4, 13.2) and 9 (5.4, 14.9) years respectively, and the duration of T1D was 23 (7, 54) months. (1) T1D children (a) 79.1% were 3-Screen positive; (b) all 3-Screen positives were individual antibody positive (GADA in 74%; IA-2A 31.1%; ZnT8A 38.7%); (c) and were younger (p=0.01 vs 3-Screen negatives); (d) multiple autoantibodies were present in 45.1%; (e) IA-2A (p=0.002) and ZnT8A (p=0.006) prevalence decreased with T1D duration. (f) TPOA and TgA prevalence was higher in T1D children compared to unaffected siblings (28%, p=0.001 and 31%, p=0.004, respectively). (2) Unaffected siblings (a) 6.3% were 3-Screen positive (p=0.001 vs T1D), and 2.4% were positive for IAA; (b) four subjects had two diabetes related autoantibodies, one of whom developed dysglycaemia during follow-up. Conclusions: The 3-Screen assay, used for the first time in Sri Lankan T1D children and their siblings as a screening tool, shows a high prevalence of T1D related Abs with a high correlation with individual assays, and is also a helpful tool in screening unaffected siblings for future T1D risk. The higher prevalence of thyroid autoantibodies in T1D children is consistent with polyglandular autoimmunity.