Persistent Hyperinsulinemic Hypoglycemia Research Articles

Crashing into Discovery: Nesidioblastosis in Adult, Unmasked post-Motor Vehicle Accident - A Case Study and Literature Review

Abstract Introduction/Objective Nesidioblastosis, characterized by pancreatic duct-derived B-islet cell proliferation, typically manifests with hypoglycemic symptoms. While more common in newborns, it can rarely affect adults. Here, we report an incidental finding of nesidioblastosis in a 37-year-old female following abdominal trauma due to a motor vehicle crash (MVC). Methods/Case Report A 37-year-old female with no notable medical history presented with blunt abdominal trauma following an MVC. The emergency evaluation revealed a grade 4 traumatic splenic laceration and severe hemoperitoneum. Preoperative lab results showed decreased hemoglobin, elevated white cell count, prolonged prothrombin time, and reduced calcium and magnesium levels. The patient underwent a splenectomy along with a distal pancreatectomy. While grossly unremarkable, microscopic examination revealed maintained acinar architecture with focal hyperplasia around pancreatic ducts. Enlarged acinar cells with pleomorphic nuclei and prominent nucleoli were consistent with focal nesidioblastosis. Results (if a Case Study enter NA) NA Conclusion Multiple studies have documented the first reported case of nesidioblastosis in adults was in 1975. While its exact incidence is uncertain, most sources suggest a relative frequency of 0.5 – 7% of persistent hyperinsulinemic hypoglycemia, with estimated overall an annual rate of around 9 per 100,000, with a higher occurrence among females. This unusual incidental discovery of nesidioblastosis in an asymptomatic patient undergoing pancreatic resection for unrelated reasons highlights the likelihood of underestimating the actual prevalence of this disease.

Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia.

Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.

Glucokinase Variant Proteins Are Resistant to Fasting-Induced Uridine Diphosphate Glucose-Dependent Degradation in Maturity-Onset Diabetes of the Young Type 2 Patients.

We previously reported that glucokinase undergoes ubiquitination and subsequent degradation, a process mediated by cereblon, particularly in the presence of uridine diphosphate glucose (UDP-glucose). In this context, we hereby present evidence showcasing the resilience of variant glucokinase proteins of maturity-onset diabetes of the young type 2 (MODY2) against degradation and, concomitantly, their influence on insulin secretion, both in cell lines and in the afflicted MODY2 patient. Hence, glucose-1-phodphate promotes UDP-glucose production by UDP-glucose pyrophosphorylase 2; consequently, UDP-glucose-dependent glucokinase degradation may occur during fasting. Next, we analyzed glucokinase variant proteins from MODY2 or persistent hyperinsulinemic hypoglycemia in infancy (PHHI). Among the eleven MODY2 glucokinase-mutated proteins tested, those with a lower glucose-binding affinity exhibited resistance to UDP-glucose-dependent degradation. Conversely, the glucokinaseA456V-mutated protein from PHHI had a higher glucose affinity and was sensitive to UDP-glucose-dependent degradation. Furthermore, in vitro studies involving UDP-glucose-dependent glucokinase variant proteins and insulin secretion during fasting in Japanese MODY2 patients revealed a strong correlation and a higher coefficient of determination. This suggests that UDP-glucose-dependent glucokinase degradation plays a significant role in the pathogenesis of glucose-homeostasis-related hereditary diseases, such as MODY2 and PHHI.

Evaluation and management of neonatal onset hyperinsulinemic hypoglycemia: a single neonatal center experience

Objectives To evaluate the clinical characteristics and treatment options of neonates requiring prolonged hospitalization due to persistent hyperinsulinemic hypoglycemia (HH). Methods This retrospective cohort study included infants >34 weeks of gestation at birth who were born in our hospital between 2018 and 2021, diagnosed with HH, and required diazoxide within the first 28 days of life. The baseline clinical characteristics, age at the time of diagnosis and treatment options in diazoxide resistance cases were recorded. Genetic mutation analysis, if performed, was also included. Results A total of 32 infants diagnosed with neonatal HH were followed up. Among the cohort, 25 infants were classified as having transient form of HH and seven infants were classified as having congenital hyperinsulinemic hypoglycemia (CHI). Thirty-one percent of the infants had no risk factors. The median birth weight was significantly higher in the CHI group, whereas no differences were found in other baseline characteristics. Patients diagnosed with CHI required higher glucose infusion rate, higher doses, and longer duration of diazoxide treatment than those in the transient HH group. Eight patients were resistant to diazoxide, and six of them required treatment with octreotide and finally sirolimus. Sirolimus prevented the need of pancreatectomy in five of six patients without causing major side effects. Homozygous mutations in the ABCC8 gene were found in four patients with CHI. Conclusions The risk of persistent neonatal hyperinsulinism should be considered in hypoglycemic neonates particularly located in regions with high rates of consanguinity. Our study demonstrated sirolimus as an effective treatment option in avoiding pancreatectomy in severe cases.

Nesidioblastosis with delayed diagnosis and post-operative complications in a patient with complex psychiatric history.

Nesidioblastosis is a rare condition of organic persistent hyperinsulinaemic hypoglycaemia, with fewer than 100 cases since it was first recorded. However, an increasing prevalence suggests previous underdiagnosis due to poor knowledge and awareness. This case describes the presentation, clinical decision-making and unique challenges in diagnosis and care of a 21-year-old female with nesidioblastosis and extensive psychiatric comorbidities. She was repeatedly misdiagnosed until 2021, despite having presented to emergency departments with hypoglycaemic symptoms for over 7 years. Her symptoms were often misattributed to behaviours secondary to restrictive anorexia nervosa and borderline personality disorder. Even after appropriate diagnosis and management, she suffered a complicated post-operative course. Patients with psychiatric comorbidities are at higher risk of distress, communication difficulties and inadequate social support, all of which could be better managed with increased multidisciplinary collaboration between endocrine, surgery, psychiatry, pain management and social work. This study highlights the importance of well-rounded patient care that addresses all facets of patient health. This approach not only improves quality of care, but also reduces overall readmissions, revisions, morbidity and mortality.

Munchausen syndrome by proxy: a case report

BackgroundInappropriately high levels of insulin secretion can cause the potentially fatal condition of persistent hyperinsulinemic hypoglycemia of infancy. Our paper focuses on another cause of severe hypoglycemia, which can be easily missed.Case presentationAn 18-month-old Saudi female was referred to our hospital for further investigation and management of her recurrent hypoglycemic attacks as a case of persistent hyperinsulinemic hypoglycemia of infancy. During admission, we noticed multiple red flags from the history; the mother was insisting on a pancreatectomy, rather than going for a positron emission tomography scan, and most importantly, all hypoglycemic attacks occurred while the mother was around. Consequently, after further investigation, the case was diagnosed as a caregiver-fabricated illness, and the case was referred to the Child Protection Center.ConclusionsOne must have a high index of suspicion to diagnose caregiver-fabricated illness. Physicians should be more attentive to prevent such a disease, which could eventually become lethal if left unnoticed.

New approaches to screening and management of neonatal hypoglycemia based on improved understanding of the molecular mechanism of hypoglycemia.

For the past 70 years, controversy about hypoglycemia in newborn infants has focused on a numerical "definition of neonatal hypoglycemia", without regard to its mechanism. This ignores the purpose of screening newborns for hypoglycemia, which is to identify those with pathological forms of hypoglycemia and to prevent hypoglycemic brain injury. Recent clinical and basic research indicates that the three major forms of neonatal hypoglycemia are caused by hyperinsulinism (recognizing also that other rare hormonal or metabolic conditions may also present during this time frame). These include transitional hypoglycemia, which affects all normal newborns in the first few days after birth; perinatal stress-induced hypoglycemia in high-risk newborns, which afflicts ∼1 in 1,200 newborns; and genetic forms of congenital hyperinsulinism which afflict ∼1 in 10,000-40,000 newborns. (1) Transitional hyperinsulinism in normal newborns reflects persistence of the low glucose threshold for insulin secretion during fetal life into the first few postnatal days. Recent data indicate that the underlying mechanism is decreased trafficking of ATP-sensitive potassium channels to the beta-cell plasma membrane, likely a result of the hypoxemic state of fetal life. (2) Perinatal stress-induced hyperinsulinism in high-risk infants appears to reflect an exaggeration of this normal low fetal glucose threshold for insulin release due to more severe and prolonged exposure to perinatal hypoxemia. (3) Genetic hyperinsulinism, in contrast, reflects permanent genetic defects in various steps controlling beta-cell insulin release, such as inactivating mutations of the K ATP-channel genes. The purpose of this report is to review our current knowledge of these three major forms of neonatal hyperinsulinism as a foundation for the diagnosis and management of hypoglycemia in newborn infants. This includes selection of appropriate interventions based on underlying disease mechanism; combined monitoring of both plasma glucose and ketone levels to improve screening for infants with persistent forms of hypoglycemia; and ultimately to ensure that infants at risk of persistent hyperinsulinemic hypoglycemia are recognized prior to discharge from the nursery.

Congenital hyperinsulinism in clinical practice: From biochemical pathophysiology to new monitoring techniques.

Congenital hyperinsulinism comprises a group of diseases characterized by a persistent hyperinsulinemic hypoglycemia, due to mutation in the genes involved in the regulation of insulin secretion. The severity and the duration of hypoglycemic episodes, primarily in the neonatal period, can lead to neurological impairment. Detecting blood sugar is relatively simple but, unfortunately, symptoms associated with hypoglycemia may be non-specific. Research in this field has led to novel insight in diagnosis, monitoring and treatment, leading to a better neurological outcome. Given the increased availability of continuous glucose monitoring systems that allow glucose level recognition in a minimally invasive way, monitoring the glycemic trend becomes easier and there are more possibilities of a better follow-up of patients. We aim to provide an overview of new available technologies and new discoveries and their potential impact on clinical practice, convinced that only with a better awareness of the disease and available tools we can have a better impact on CHI diagnosis, prevention and clinical sequelae.

Carbamazepine promotes surface expression of mutant Kir6.2-A28V ATP-sensitive potassium channels by modulating Golgi retention and autophagy

Pancreatic β-cells express ATP-sensitive potassium (KATP) channels, consisting of octamer complexes containing four sulfonylurea receptor 1 (SUR1) and four Kir6.2 subunits. Loss of KATP channel function causes persistent hyperinsulinemic hypoglycemia of infancy (PHHI), a rare but debilitating condition if not treated. We previously showed that the sodium-channel blocker carbamazepine (Carb) corrects KATP channel surface expression defects induced by PHHI-causing mutations in SUR1. In this study, we show that Carb treatment can also ameliorate the trafficking deficits associated with a recently discovered PHHI-causing mutation in Kir6.2 (Kir6.2-A28V). In human embryonic kidney 293 or INS-1 cells expressing this mutant KATP channel (SUR1 and Kir6.2-A28V), biotinylation and immunostaining assays revealed that Carb can increase surface expression of the mutant KATP channels. We further examined the subcellular distributions of mutant KATP channels before and after Carb treatment; without Carb treatment, we found that mutant KATP channels were aberrantly accumulated in the Golgi apparatus. However, after Carb treatment, coimmunoprecipitation of mutant KATP channels and Golgi marker GM130 was diminished, and KATP staining was also reduced in lysosomes. Intriguingly, Carb treatment also simultaneously increased autophagic flux and p62 accumulation, suggesting that autophagy-dependent degradation of the mutant channel was not only stimulated but also interrupted. In summary, our data suggest that surface expression of Kir6.2-A28V KATP channels is rescued by Carb treatment via promotion of mutant KATP channel exit from the Golgi apparatus and reduction of autophagy-mediated protein degradation.

F-18 DOPA PET/CT in pediatric patients with hyperinsulinemic hypoglycemia: A correlation with genetic analysis.

Persistent hyperinsulinemic hypoglycemia is a rare but life-threatening disease of infancy and childhood. 18F-DOPA PET/CT has been shown to be a useful modality in the localization of focal pancreatic lesions in these patients. We aimed to assess the role of 18F-DOPA PET/CT in such patients at our institution. In this prospective study, 18F-DOPA PET/CT scans and clinical details of 20 children with clinical diagnosis of hyperinsulinemic hypoglycemia were reviewed. Scans were acquired at 5 min postinjection of 2-3 mCi of 18F-DOPA on dedicated PET/CT scanners (Biograph mCT, Siemens Inc and Discovery PET/CT, GE). Abdominal spot images over 1-2 bed positions were acquired. Additionally, genetic mutation status, where available, was correlated to the scan findings. Out of 20 children (7 female and 13 male), 13 were infants. The age of the children ranged from 3 months to 8 years. Fifteen children had undergone gene analysis, 12 were positive for mutation in ABCC8, 1 for GLUD-1, 1 for GCK mutations and 1 had not shown any mutation. 18F-DOPA PET/CT scan showed 5 focal pancreatic lesions in 5 children (1 in each), two focal lesions in 1 child and diffuse pancreatic uptake in 14 children. 18F-DOPA PET/CT is a useful modality for localizing focal pancreatic lesions in children with persistent hyperinsulinemic hypoglycemia. The detection rate is significantly higher in patients with ABCC8 paternal monoallelic recessive gene mutation. 18F-DOPA PET/CT scan consequent to findings on genetic analysis appears to be useful in planning the management of children with hyperinsulinism.

Laparoscopic near-total pancreatectomy for persistent hyperinsulinemic hypoglycemia in infants and children

Laparoscopic near-total pancreatectomy for persistent hyperinsulinemic hypoglycemia in infants and children

Congenital hyperinsulinism: localization of a focal lesion with 18F-FDOPA positron emission tomography

Hyperinsulinemic hypoglycemia of infancy, also known as congenital hyperinsulinism, is a group of disorders characterized by dysregulated insulin release. Neonates with severe, persistent hyperinsulinemic hypoglycemia who are unresponsive to medical therapy require pancreatectomy to prevent brain damage from hypoglycemia. To date, multiple genetic mutations and syndromes and several unique histopathological entities have been identified in children with hyperinsulinism. Histopathology is characterized as diffuse, focal or atypical. Surgical resection of a focal lesion results in a cure in up to 97% of these children. Imaging with 6-fluoro-(18F)-L-3,4-dihydroxyphenylalanine (18F-FDOPA) positron emission tomography (PET) is the test of choice for identifying and localizing a focal lesion and has proved to be an invaluable guide for surgical resection. Genetic evaluation is essential for determining who will benefit from PET imaging. This article provides an approach to determine who should be imaged, how to set up a protocol and how to interpret the imaging findings. The diagnosis and management of this disorder require a multidisciplinary approach to prevent brain damage from hypoglycemia.

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 of64.7% of the children showed mild to moderate developmental delay. Therefore, it seems that long-term resolution of HH in children with negative genetics for KATP channel genes who required diazoxide for over 2 years will ensue, and thus regular evaluation is crucial. The possible molecular mechanisms involved are unclear.

Sirolimus in infants with congenital hyperinsulinism (CHI) - a single-centre experience.

Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycaemia in neonates and infants. Medical treatment includes the use of high concentrations of glucose and combinations of diazoxide, octreotide and glucagon. We report our experience of using sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, in the treatment of CHI in seven newborns who are poorly responding to standard medical therapy. Majority (87%) of infants achieved euglycaemia using a combination of oral feeding and the addition of sirolimus to standard medical treatment. One infant who failed to achieve euglycaemia even after surgery managed successfully with sirolimus. Diagnosis was confirmed by genetics evaluation; in three infants, novel mutations were detected. Outcome and long-term follow-up of all cases are described.Conclusion: Sirolimus can be considered in treatment of CHI refractory to standard medical treatment or in cases unresponsive to surgical treatment. What is Known: • Congenital hyperinsulinism (CHI) or persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI) associated with mutations such as the ABBC8 or KCNJ gene known to cause hypoglycaemia refractory to standard medical treatment such as diazoxide and octreotide and may need subtotal pancreatectomy (STP). • Sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, was recently reported to be useful for refractory CHI cases with variable efficacy. What is New: • Our case series describes efficacy and safety of sirolimus in seven genetically proven refractory CHI cases with mainly neonatal presentation. All patients' follow-ups are described. • Out of seven infants, six infants responded well to sirolimus, and among these one infant who failed to respond to surgery (STP) also successfully managed with sirolimus. • It highlights the right patient selection and right dose to successfully manage these cases without much adverse effects.

Familial Hyperinsulinism due to HNF4A Deficiency and Benign Premature Adrenarche: A Case Report

Background: Familial Hyperinsulinism due to HNF4A deficiency (FHI-HNF4A) is a form of diazoxide-sensitive, diffuse hyperinsulinism, characterized by transient or persistent hyperinsulinemic hypoglycemia, and a propensity to develop Maturity-Onset Diabetes of the Young type 1 (MODY1). The association between FHI-HNF4A deficiency and benign premature adrenarche (BPA) is unknown.
 The Case: We report the case of a 5-year-old girl with FHI-HNF4A, controlled on diazoxide, who presented with BPA and Tanner stage III pubic hair associated with body odor and acne. Work-up revealed elevated dehydroepiandrosterone sulfate (DHEAS), elevated free testosterone, and advanced bone age. Insulin levels were elevated in the setting of normal fasting blood glucose. We discuss the possible hormonal underpinnings of hyperandrogenism.
 Conclusion: Though the underlying pathophysiology of this phenotype is unclear, a possible synergistic mechanism exists between insulin-induced hyperandrogenism and HNF4A deficiency leading to a transient decrease of SHBG and thus increased free testosterone levels. Further investigation is required to determine the association between HNF4A dysfunction and BPA.

Persistent Hyperinsulinemic Hypoglycemia in Infancy-A Case Report


 
 
 
 Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is one of the commonest reasons for severe, intractable hypoglycemia in neonates. Dysregulated insulin secretion is the major underlying pathogenesis which results in hyperinsulinemia, hypoketonemia and hypofatty acidemia. The management is extremely complicated. Early diagnosis and aggressive management of hyperinsulinemic hypoglycemia is essential for prevention of hypoglycemia induced neuronal injury. Here we describe a baby diagnosed as PHHI who was unresponsive to medical management with diazoxide and underwent near total pancreatectomy. Genetic work up revealed a homozygous termination mutation in ABCC8 gene at amino acid position 1452 with heterozygosity in both parents.
 
 
 

Persistent Hypoglycemia and Seizures in Two Months Old Infant Due to Recurrent Hyper insulinemic Hypoglycemia

Persistent hyperinsulinemic hypoglycaemia is the most common cause of recurrent hypoglycaemia. Neonatal hypoglycemia, is a heterogeneous disorder with plasma glucose level of less than 30mg/dL in first 24hrs of life and less than 40mg/dL thereafter, is the most common metabolic cause in newborns. The most important feature of neurologic dysfunction in neonatal period is the occurrence of seizures which can be due to metabolic disorders, genetic disorders, intracranial infections, malformation syndromes, benign neonatal seizures, hemorrhage. Here, we provide a description of a 2 months old infant with Persistent Hypoglycemia and Seizures, treated with hypoglycemic management and antiepileptic drugs

A Novel HNF4A Mutation Causing Three Phenotypic Forms of Glucose Dysregulation in a Family

Maturity-onset diabetes of the young (MODY) classically describes dominantly inherited forms of monogenic diabetes diagnosed before 25 years of age due to pancreatic β-cell dysfunction. In contrast, mutations in certain MODY genes can also present with transient or persistent hyperinsulinemic hypoglycemia in newborn infants, reflecting instead β-cell dysregulation. Of the MODY genes described to date, only hepatocyte nuclear factor-4-alpha (HNF4A; MODY1) and hepatocyte nuclear factor-1-alpha (HNF1A; MODY3) mutations may result in a biphasic phenotype of hypoglycemia in early life and hyperglycemia in later life. We report a family with a novel HNF4A mutation with diverse phenotypic presentations of glucose dysregulation. The proband was a term, appropriate-for-gestational age male infant with symptomatic hypoglycemia on day 3 of life needing high glucose infusion rate to maintain normoglycemia. He was born to a non-obese and non-diabetic mother. Glucose regulation was optimized using diazoxide upon confirmation of hyperinsulinism. Cascade genetic screening identified the same mutation in his father and elder sister, but mother was negative. Father was diagnosed with Type 1 diabetes at 15 years of age that required insulin therapy. Proband's elder sister, born at term appropriate for gestational age, presented with transient neonatal hypoglycemia needing parenteral glucose infusion for a week followed by spontaneous resolution. The paternal grandparents were negative for this mutation, confirming a paternal de novo mutation and autosomal dominant inheritance in this family. This pedigree suggests that the presence of early-onset paternal diabetes should prompt molecular testing in infants presenting in the newborn period with diazoxide-responsive hyperinsulinemic hypoglycemia, even in the absence of maternal diabetes and macrosomia.

A suspected insulinoma with the unexpected histopathological finding of a nesidioblastosis – A case report and literature review

Introduction: Nesidioblastosis is a hyperplasia of the beta cells that causes persistent hyperinsulinemic hypoglycemia, unfortunately, it is difficult to diagnose through imaging studies. Case presentation: A 68-year-old woman with palpitations, diaphoresis, dizziness and alterations in the level of consciousness that improve with food intake. Laboratories: glucose 35.0 mg/dl, insulin 12.5 mUI/ml, proinsulin 14.1 pmol/L and peptide C 2.55 ng/ml. Octreoscan reveals an abnormal epigastric uptake area and the tomography shows a focal hypervascular lesion in pancreatic body of 12×11 mm. A distal pancreatectomy was performed without palpating the tumor in transoperative period, and a diffuse nesiodioblastosis was reported in the histopathological study. The patient persists with hypoglycemia and an additional pancreatic resection was performed, resecting 90% of the organ. Although an insulinoma was not located in the piece, an area surrounded by connective tissue was observed where islet hyperplasia was more accentuated. Discussion: The pathophysiology of nesidioblastosis is unknown, its main differential diagnosis is insulinoma and this should be suspected when the tumor can not be identified. Most agree that a pancreatectomy that involves 60-80% of the total organ can control glucose levels with low risk of diabetes and pancreatic insufficiency. Conclusion: The nesidioblastosis should be suspected when a hyperinsulinemic hypoglycemia is difficult to control and when a tumor can not be identified. The extension of the pancreatectomy should be individualized and if an insulinoma is not localized and a nesidioblastosis is suspected, an intraoperative histopathological examination with frozen section evaluation for the margins could determine the extent of pancreatectomy.

Hyperinsulinemic hypoglycemia in seven patients with de novo NSD1 mutations

This study describes 7 individuals with hyperinsulinemic hypoglycemia caused by NSD1 gene mutations with 3 having persistent hyperinsulinemic hypoglycemia.