Congenital hyperinsulinism

Congenital hyperinsulinism in a newborn presenting with poor feeding

Hyperinsulinemic hypoglycemia is a condition linked to several genetic, metabolic, and growth disorders in which there is dysregulated insulin secretion. In infants, an inappropriately persistent hypoglycemic and hypoketotic state can cause severe brain injury leading to epilepsy, cerebral palsy, and neurodevelopmental disabilities due to the lack of glucose and ketone substrate to serve as fuel for the developing brain. The most common cause of persistent hypoglycemia in neonates and children has been found to be congenital hyperinsulinism. Here, we report a child with a unique presentation, found to have a novel genetic variant as the underlying cause of hyperinsulinism. This case study highlights the importance of maintaining a broad differential and considering a diagnosis of congenital hyperinsulinism in a baby with poor feeding in the newborn period. Recognizing and treating congenital hyperinsulinism is essential to prevent potential neurological sequelae from recurrent, severe hypoglycemia.

A Newborn with Congenital Hyperinsulinism

Objective: Our aim was to describe the molecular alterations in the ABCC8 gene in a child with congenital hyperinsulinism (CHI). Methods: Genetic analysis of the ABCC8 gene of a newborn infant with congenial hyperinsulinism was obtained. Results: There were two mutations in the ABCC8 gene, c.4412delT, and c.3979G > A, indicating a compound heterozygous mutation. The c.4412delT variant is associated with CHI, and the c.3979G > A variant is associated with neonatal diabetes. Treatment with diazoxide was not effective, octreotide treatment with acetate was effective. Conclusion: The combination of a mutation of the ABCC8 gene c.4412delT, associated with CHI, and the mutation of c.3979G > A, associated with neonatal diabetes, resulted in a neonate with hypoglycemia. The mechanism remains unclear.

Congenital hyperinsulinism treated by surgical resection of the hyperplastic lesion which had been preoperatively diagnosed by 18F-DOPA PET examination in Japan: a nationwide survey

PURPOSE

Congenital hyperinsulinism is a rare disease, and the newly developed 18 fluoro-_L-dihydroxyphenylalanine-positron emission tomography (18F-DOPA PET) examination can detect hyperplastic lesions. Our purpose was to report the results of a nationwide survey on surgical treatment of congenital hyperinsulinism in Japan.

METHODS

A questionnaire was sent to the 159 accredited and affiliated training institutes certified as pediatric surgical institutes by the Japanese Association of Pediatric Surgeons, asking if they had encountered patients who underwent surgical treatment for congenital hyperinsulinism after 18F-DOPA PET examination from 2000 to 2017. Six institutes answered that they had treated such cases, and the total number of cases was 14.

RESULTS

18F-DOPA PET examination detected the focal lesion in 12 of the 14 cases. 18F-DOPA PET examination could accurately determine the site of the hyperplastic lesion in the pancreas in 11 (91.7%) of the 12 cases. All cases underwent surgical resection of the hyperplastic lesion at under 2 years of age.

CONCLUSION

Surgical resection of a focal hyperplastic lesion in the pancreas was a safe and effective treatment if the hyperplastic lesion was a focal lesion. However, it is necessary to check the exact distribution of the lesion by intraoperative pathologic examination of frozen sections.

Current Status of Childhood Hyperinsulinemic Hypoglycemia in Turkey

Congenital hyperinsulinism (CHI) is a rare disease characterized by dysregulated insulin secretion from pancreatic β-cells. Recurrent hypoglycemia can lead to neurological insult and permanent brain injury. Recently, there are important advances in understanding the genetic mechanisms, histological characteristics, imaging, and surgical techniques of congenital hyperinsulinemic hypoglycemia that could reflect to improvement in the clinical care of infants with this disorder. In Turkey, there is a high rate of consanguinity, thus, the incidence of CHI is expected to be high. Until now, there are no nationwide data regarding the disorder, and some individual case reports or case series had been published. Determining the characteristics of Turkish patients with CHI can help develop a different perspective on this rare disease. In this review, we evaluated the clinical and molecular characteristics of Turkish patients with CHI based on reports published in the literature. The most frequently seen mutations were ABCC8 gene mutations (n=37), followed by HADH (n=11) and KCNJ11 gene (n=7) mutations. A total of 141 Turkish patients with CHI were reported until now. Among them, 115 patients had been genetically analyzed, and 56 of them had one of the mutation leading to hyperinsulinism.

Congenital hyperinsulinism: exclusive human milk and breastfeeding

Congenital hyperinsulinism is a genetic condition causing dysregulation of insulin and results in persistent hypoglycemia. The most common types are sulfonylurea receptor (SUR1), potassium inward rectifying channel (Kir6.2), glutamate dehydrogenase (GDH), and glucokinase (GK), with SUR1 and Kir6.2 being the most prevalent. It is imperative that these infants undergo diagnostic testing, which includes genetic, neonatal fasting study to induce hypoglycemia, glucagon stimulation, and imaging. Once a diagnosis has been made, surgical intervention may be needed to help regulate blood glucose levels. During this diagnostic process and as the infant is undergoing treatment, there may be little concern for the mother's feeding plan. Because human milk is the preferred form of nutrition for all infants, these mothers should receive prenatal counseling regarding the initiation and maintenance of milk supply. Parenteral nutrition may be necessary to maintain blood glucose to support human milk administration and breastfeeding.