Clinical characteristics and long-term outcome of Taiwanese children with congenital hyperinsulinism

Congenital hyperinsulinism and surgical outcome in a single tertiary center in Brazil

OBJECTIVE

Congenital hyperinsulinism (CHI) is a heterogeneous genetic disease characterized by increased insulin secretion and causes persistent hypoglycemia in neonates and infants due to dysregulation of insulin secretion by pancreatic β cells. Babies with severe hypoglycemia and for whom medical treatment has been ineffective usually require surgical treatment with near-total pancreatectomy. To evaluate the clinical and surgical aspects affecting survival outcomes in babies diagnosed with CHI in a single tertiary care center.

METHODS

Retrospective Cohort study involving a single university tertiary center for the treatment of CHI. The authors study the demographics, clinical, laboratory, and surgical outcomes of this casuistic.

RESULTS

61 % were female, 39 % male, Birth weight: 3576 g (±313); Age of onset of symptoms: from the 2nd hour of life to 28 days; Time between diagnosis and surgery ranged between 10 and 60 days; Medical clinical treatment, all patients received glucose solution with a continuous glucose infusion and diazoxide. 81 % of the patients used corticosteroids, 77 %. thiazide, 72 % octreotide, 27 % nifedipine; Neurological sequelae during development and growth: 54 % had some degree of delay in neuropsychomotor development, 27 % obesity. Surgery was performed open in 6 and 12 minimally invasive surgery (MIS).

HISTOPATHOLOGY

2 focal and 16 diffuse, Length of stay (days) was lower in MIS (p < 0.05). Survival was 100 %.

CONCLUSIONS

CHI is a rare and difficult-to-manage tumor that must be performed in a multidisciplinary and tertiary center. Most surgical results are good and the laparoscopic approach to disease has been the best choice for patients.

Genotype-phenotype correlation in Taiwanese children with diazoxide-unresponsive congenital hyperinsulinism

Objective

Congenital hyperinsulinism (CHI) is a group of clinically and genetically heterogeneous disorders characterized by dysregulated insulin secretion. The aim of the study was to elucidate genetic etiologies of Taiwanese children with the most severe diazoxide-unresponsive CHI and analyze their genotype-phenotype correlations.

Methods

We combined Sanger with whole exome sequencing (WES) to analyze CHI-related genes. The allele frequency of the most common variant was estimated by single-nucleotide polymorphism haplotype analysis. The functional effects of the ATP-sensitive potassium (KATP) channel variants were assessed using patch clamp recording and Western blot.

Results

Nine of 13 (69%) patients with ten different pathogenic variants (7 in ABCC8, 2 in KCNJ11 and 1 in GCK) were identified by the combined sequencing. The variant ABCC8 p.T1042QfsX75 identified in three probands was located in a specific haplotype. Functional study revealed the human SUR1 (hSUR1)-L366F KATP channels failed to respond to intracellular MgADP and diazoxide while hSUR1-R797Q and hSUR1-R1393C KATP channels were defective in trafficking. One patient had a de novo dominant mutation in the GCK gene (p.I211F), and WES revealed mosaicism of this variant from another patient.

Conclusion

Pathogenic variants in KATP channels are the most common underlying cause of diazoxide-unresponsive CHI in the Taiwanese cohort. The p.T1042QfsX75 variant in the ABCC8 gene is highly suggestive of a founder effect. The I211F mutation in the GCK gene and three rare SUR1 variants associated with defective gating (p.L366F) or traffic (p.R797Q and p.R1393C) KATP channels are also associated with the diazoxide-unresponsive phenotype.

Case of Insulinoma in a 2-Months-Old Infant

INTRODUCTION: Insulinoma is congenital hyperinsulinism of infancy (CHI). It is a type of functional neuroendocrine tumor (NET) in the pancreas that manifests with persistent hypoglycemia caused by inappropriately high secretion of insulin (hyperinsulinemia). Comprehensive and multidisciplinary management is required for a better outcome. CASE PRESENTATION: A 2-months-old girl came to the Emergency unit Sanglah Hospital, with a chief complaint of seizure. The patient had a low blood glucose level, high fasting insulin, high LDH, computed tomography of the abdomen result showed isodense heterogeneous lesions border in the cauda pancreas with size 1.32 × 1.24 × 1.35 cm. The anatomy-pathological result showed pancreatic neuroendocrine tumor WHO Grade II, functional, consistent, and clinically to insulinoma on the tail of the pancreas. The patient was treated with hydrocortisone, nifedipine, and octreotide. The patient underwent laparotomy partial pancreatectomy. In post-surgery condition, she had good drink tolerance, no episode of recurrent seizure, and blood glucose was controlled. CONCLUSION: Insulinoma is a rare disease. The diagnosis was challenging. This case report presents the diagnostic work-up and management of a patient with a persistent hypoglycemia condition that was diagnosed as insulinoma.

When is it best to discontinue diazoxide in children with persistent hyperinsulinaemic hypoglycaemia and negative genetics for KATP channel gene variants?

Diazoxide is the first-line treatment in children with hyperinsulinaemic hypoglycaemia (HH); however, limited information is available on the duration of diazoxide treatment in children who require over 2 years of it. Hence, we retrospectively reviewed the clinical and biochemical aspects, as well as the duration of therapy and neurodevelopmental assessment, in genetically uncharacterised diazoxide-responsive HH patients admitted to a tertiary hospital over the last 16 years, who had successfully discontinued diazoxide and remained euglycaemic. To exclude transient HH forms, only patients that required diazoxide for over 2 years were studied. We identified a total of 17 patients (70% males), in whom HH was diagnosed between 1 day and 18 months of age, and 88% were born at term with a median birth weight of 3.79 kg. All children responded to diazoxide at a median dose of 11.5 mg/kg/day, and it was stopped at a median age of 8.5 years, with a median duration of therapy of 7.25 years. The cases that required diazoxide the longest manifested no specific biochemical or clinical characteristics. Fasting tests performed after diazoxide discontinuation showed no longer requirement of diazoxide in all the cases. A total of 64.7% of the children showed mild to moderate developmental delay. Therefore, it seems that long-term resolution of HH in children with negative genetics for K_ATP channel genes who required diazoxide for over 2 years will ensue, and thus regular evaluation is crucial. The possible molecular mechanisms involved are unclear.

Risk Factors for Adverse Neurodevelopment in Transient or Persistent Congenital Hyperinsulinism

OBJECTIVE

Aim was to identify hypotheses why adverse neurodevelopment still occurs in children with transient or persistent hyperinsulinism despite improvements in long-term treatment options during the last decades.

MATERIAL AND METHODS

A retrospective review of 87 children with transient (n=37) or persistent congenital hyperinsulinism (CHI) (n=50) was conducted at the University Children's Hospital Duesseldorf, Germany. Possible risk factors for neurodevelopmental sequelae due to hypoglycemia were analyzed with a focus on the first days after onset of disease.

RESULTS

Median age at follow-up was 7 years (IQR 8). Adverse neurodevelopmental outcome was seen in 34.5% (n=30) of all CHI patients. Fifteen had mildly abnormal neurodevelopment and 15 had a severe hypoglycemic brain injury. In univariate analysis, mildly abnormal neurodevelopment was associated with the diagnosis of persistent CHI (odds ratio (OR) 8.3; p=0.004) and higher birth weight (mean difference 1049 g; p<0.001). Severe hypoglycemic brain injury was associated with the diagnosis of persistent CHI (OR 5.1; p=0.013), being born abroad (OR 18.3; p<0.001) or in a lower-level maternity hospital (OR 4.8; p=0.039), and of note history of hypoglycemic seizures (OR 13.0; p=<0.001), and a delay between first symptoms of hypoglycemia and first blood glucose measurement/initiation of treatment (OR 10.7; p<0.001). Children with severe hypoglycemic brain injury had lower recorded blood glucose (mean difference -8.34 mg/dl; p=0.022) and higher birth weight than children with normal development (mean difference 829 g; p=0.012). In multivariate binary logistic regression models, lowest blood glucose <20 mg/dl (OR 134.3; p=0.004), a delay between initial symptoms and first blood glucose measurement/initiation of treatment (OR 71.7; p=0.017) and hypoglycemic seizures (OR 12.9; p=0.008) were positively correlated with severe brain injury. Analysis showed that the odds for brain injury decreased by 15% (OR 0.85; p=0.035) if the blood glucose increased by one unit.

CONCLUSION

While some risk factors for adverse outcome in CHI are not influenceable, others like lowest recorded blood glucose values <20 mg/dl, hypoglycemic seizures, and insufficiently-or even untreated hypoglycemia can be avoided. Future guidelines for management of neonatal hypoglycemia should address this by ensuring early identification and immediate treatment with appropriate escalation steps.

Genotype and phenotype analysis of a cohort of patients with congenital hyperinsulinism based on DOPA-PET CT scanning

Congenital hyperinsulinism (CHI) is a clinically, genetically, and morphologically heterogeneous disorder. ¹⁸F DOPA-PET CT scanning greatly improves its clinical outcome. Here, we presented the first Chinese ¹⁸F DOPA-PET CT scanning-based CHI cohort highlighting the variable ethic clinical phenotypes and genotypes. Fifty CHI patients were recruited. Median age at presentation was 2 days. Median fasting time was 2 h. Mean insulin level was 25.6 μIU/ml. Fifty-two percent of patients were diazoxide-unresponsive with significantly shorter fasting tolerance time and higher serum insulin level compared with the responsive patients. Seventy-four percent of patients experienced at least one adverse drug reaction. Tremendously increased focal lesions (32%) were detected and 75% of them were cured through surgery. Thirty-one nucleotide sequence changes were identified in 48% patients. Four novel variants (Q608X, Q1347X, Q289X, F1489S) in ABCC8 gene and 2 novel variants (G132A, V138E) in KCNJ11 gene were detected. Of the variants, 87.1% harbored in ABCC and KCNJ11 genes. T1042Qfs*75 in ABCC8 gene was the most common mutation.Conclusion: Highly increased portion of focal lesion was presented in Chinese CHI patients compared with that of the previous reports. Intolerance to diazoxide was much more evident in Chinese or East Asian than other populations. Certain hotspot mutations harbored in Chinese CHI patients. What is Known: • ¹⁸F DOPA-PET CT scanning can provide informative guidance for surgical procedure when medical therapy is not well responded in CHI patients. What is New: • Intolerance to diazoxide is much more evident in Chinese and East Asian CHI patients compared with the other ethnic populations. • Novel mutations were detected in ABCC8 and KCNJ11 gene. Hotspot mutations such as T1042Qfs*75, I1511K, E501K, G111R in ABCC8 gene, and R34H in KCNJ11 gene are predominantly responsible for Chinese CHI patients.

Congenital Hyperinsulinism in China: A Review of Chinese Literature Over the Past 15 Years

OBJECTIVE

Congenital hyperinsulinism (CHI) is a rare but severe cause of hypoglycemia. The present study investigates the clinical presentation, therapeutic outcomes and genetic mutations of CHI in Chinese individuals over the past 15 years.

METHODS

The authors retrospectively reviewed one case in their department and 206 cases reported from January 2002 to October 2016 in China. PubMed, Ovid Medline, Springer and Wanfang Database, CBMD database, and CKNI database were the sources used to collect the data.

RESULTS

In total, 207 cases were recruited. Of these, the ages of 100 (48.3%) were within the 4th week after birth. Seventy-seven cases (37.2%) were born large for gestational age (LGA). Seizures occurred in 140 cases (67.6%). Among 140 cases (67.6%) who were administered diazoxide treatment, 90 (64.3%) were responsive. Seven cases (3.4%) received octreotide treatment and 19 cases (9.2%) underwent surgery. 63/129 cases (48.8%) were detected to have gene mutations, including ABCC8 (69.8%), KCNJ11 (12.7%), GLUD1, GCK, HADH, and HNF4A. Among the diazoxide-unresponsive cases, gene mutations were detected in 20/36 (55.6%) cases with ABCC8 and in 2 (5.6%) cases with KCNJ11. Among the diazoxide-responsive cases, gene mutations were detected in 8 patients with ABCC8, 4 with KCNJ11, 5 with GLUD1, and 1 with GCK.

CONCLUSION

The present study indicates that most CHI cases occurred in neonates and that 1/3 of the cases were born LGA. ABCC8 and KCNJ11 are the most common gene mutations. More than half of the diazoxide-unresponsive CHI detected mutations are in ABCC8 and KCNJ11 genes. The GLUD1 gene mutations cause diazoxide-responsive CHI. Identifying the gene mutations can assist in the diagnosis and treatment of CHI.

Computer-determined dosage of insulin in the management of neonatal hyperglycaemia (HINT2): protocol of a randomised controlled trial

INTRODUCTION

Neonatal hyperglycaemia is frequently treated with insulin, which may increase the risk of hypoglycaemia. Computer-determined dosage of insulin (CDD) with the STAR-GRYPHON program uses a computer model to predict an effective dose of insulin to treat hyperglycaemia while minimising the risk of hypoglycaemia. However, CDD models can require more frequent blood glucose testing than common clinical protocols. The aim of this trial is to determine if CDD using STAR-GRYPHON reduces hypoglycaemia in hyperglycaemic preterm babies treated with insulin independent of the frequency of blood glucose testing.

METHODS AND ANALYSIS

Design: Multicentre, non-blinded, randomised controlled trial.

SETTING

Neonatal intensive care units in New Zealand and Australia.

PARTICIPANTS

138 preterm babies ≤30 weeks' gestation or ≤1500 g at birth who develop hyperglycaemia (two consecutive blood glucose concentrations ≥10 mmol/L, at least 4 hours apart) will be randomised to one of three groups: (1) CDD using the STAR-GRYPHON model-based decision support system: insulin dose and frequency of blood glucose testing advised by STAR-GRYPHON, with a maximum testing interval of 4 hours; (2) bedside titration: insulin dose determined by medical staff, maximum blood glucose testing interval of 4 hours; (3) standard care: insulin dose and frequency of blood glucose testing determined by medical staff. The target range for blood glucose concentrations is 5-8 mmol/L in all groups. A subset of babies will have masked continuous glucose monitoring.

PRIMARY OUTCOME

is the number of babies with one or more episodes of hypoglycaemia (blood glucose concentration <2.6 mmol/L), during treatment with insulin.

ETHICS AND DISSEMINATION

This protocol has been approved by New Zealand's Health and Disability Ethics Committee: 14/STH/26. A data safety monitoring committee has been appointed to oversee the trial. Findings will be disseminated to participants and carers, peer-reviewed journals, guideline developers and the public.

TRIAL REGISTRATION NUMBER

12614000492651.