Intra-arterial calcium stimulation test in the investigation of hyperinsulinaemic hypoglycaemia

Somatostatin receptors in congenital hyperinsulinism: Biology to bedside

Congenital hyperinsulinism (CHI), although a rare disease, is an important cause of severe hypoglycemia in early infancy and childhood, causing preventable morbidity and mortality. Prompt diagnosis and appropriate treatment is necessary to prevent hypoglycaemia mediated brain damage. At present, the medical treatment of CHI is limited to diazoxide as first line and synthetic somatostatin receptor ligands (SRLs) as second line options; therefore understanding somatostatin biology and treatment perspectives is important. Under healthy conditions, somatostatin secreted from pancreatic islet δ-cells reduces insulin release through somatostatin receptor induced cAMP-mediated downregulation and paracrine inhibition of β- cells. Several SRLs with extended duration of action are now commercially available and are being used off-label in CHI patients. Efficacy remains variable with the present generation of SRLs, with treatment effect often being compromised by loss of initial response and adverse effects such as bowel ischaemia and hepatobiliary dysfunction. In this review we have addressed the biology of the somatostatin system contexualised to CHI. We have discussed the clinical use, limitations, and complications of somatostatin agonists and new and emerging therapies for CHI.

Diagnosis of functioning pancreaticoduodenal neuroendocrine tumors

Functioning pancreaticoduodenal neuroendocrine tumors (PD-NETs) are popular in a textbook, but they are still unfamiliar to a general clinician, and delay of diagnosis or misdiagnosis has been reported even today. It is a consensus that sporadic functioning PD-NET is cured only by surgical resection. So, early detection and early resection is the gold standard for the treatment of functioning PD-NET. Functioning PD-NETs in patients with multiple endocrine neoplasia type 1 (MEN 1) are often multiple. You should check about MEN 1 whenever you encountered multiple PD-NET. They are diagnosed in younger age than sporadic cases. In most cases they are accompanied with numerous microscopic or macroscopic nonfunctioning P-NETs, which are potentially metastatic and the most common cause of death in MEN 1 patients.

Integrating genetic and imaging investigations into the clinical management of congenital hyperinsulinism

Congenital Hyperinsulinism (CHI) is a rare but important cause of hypoglycaemia in infancy. CHI is a heterogeneous disease, but has a strong genetic basis; a number of genetic causes have been identified with CHI in about a third of individuals, chiefly in the genes that code for the ATP sensitive K(+) channels (KATP ) in the pancreatic β-cells. Rapid KATP channel gene testing is a critical early step in the diagnostic algorithm of CHI, with paternal heterozygosity correlating with the occurrence of focal lesions. Imaging investigations to diagnose and localize solitary pancreatic foci have evolved over the last decade with (18)F-DOPA PET-CT scanning as the current diagnostic tool of choice. Although clinical management of CHI has improved significantly with the application of genetic screening and imaging investigations, much remains to be uncovered. This includes a better understanding of the molecular mechanisms for dysregulated insulin release in those patients without known genetic mutations, and the development of biomarkers that could characterize CHI, including long-term prognosis and targeted treatment planning, i.e. 'personalised medicine'. From the perspective of pancreatic imaging, it would be important to achieve greater specificity of diagnosis not only for focal lesions but also for diffuse and atypical forms of the disease.

Pancreatic head resection and Roux-en-Y pancreaticojejunostomy for the treatment of the focal form of congenital hyperinsulinism

PURPOSE

To determine the outcome of patients who underwent pancreatic head resection and Roux-en-Y pancreaticojejunostomy to the remaining normal pancreatic body and tail for the treatment of a focal lesion in the pancreatic head causing congenital hyperinsulinism (HI).

METHODS

One hundred thirty-eight patients underwent pancreatic resection for focal HI between 1998 and 2010. Twenty-three patients in the group underwent pancreatic head resection and Roux-en-Y pancreaticojejunostomy.

RESULTS

There were 13 females and 10 males. Median age and weight at surgery were 8 weeks and 5.8 kg, respectively. Twenty-one patients had a near-total pancreatic head resection, and 2 patients had a pylorus-preserving Whipple procedure. The pancreaticojejunostomy anastomosis was performed with interrupted fine monofilament sutures such that the transected end of the pancreatic body was tucked within the end of the Roux-en-Y jejunal limb. Median hospital stay was 22 days. All patients were cured of HI.

CONCLUSION

We conclude that pancreatic head resection with Roux-en-Y pancreaticojejunostomy is a safe and effective procedure for the treatment of the HI patient with a large focal lesion in the pancreatic head that is not amenable to local resection alone.

The laparoscopic approach toward hyperinsulinism in children

Hyperinsulinemic hypoglycemia (HH) in children requiring surgery is rare. Early HH can be the result of focal or diffuse pancreatic pathology. A number of genetic abnormalities in early HH have been identified, but in the majority of patients no abnormality is found. The sporadic focal and diffuse forms as well the autosomal recessive form are particularly therapy-resistant and demand for early surgery. Preoperative discrimination between focal and diffuse disease in early HH is difficult. 18 F DOPA PET in combination with CT is promising as is laparoscopic exploration of the pancreas. Frozen section biopsy analysis has not been uniformly beneficial. If macroscopically no focal lesion is found, limited laparoscopic distal pancreatectomy provides tissue for definitive pathologic examination. Subsequent near total laparoscopic spleen-saving pancreatectomy surgery is not particularly difficult. Later HH may occur in the context of the MEN-1 syndrome and is then multifocal in nature. In MEN-1 patients, a distal spleen-saving pancreatectomy with enucleation of lesions in the head seems justified. Insulin-producing lesions in non-MEN-1 patients should be enucleated. There should always be a suspicion of malignancy. Also, in older children, surgery for hyperinsulinism should be performed laparoscopically.

Clinical features and morphological characterization of 10 patients with noninsulinoma pancreatogenous hypoglycaemia syndrome (NIPHS)

OBJECTIVE

Noninsulinoma pancreatogenous hypoglycaemia syndrome (NIPHS), characterized by postprandial neuroglycopaenia, negative prolonged fasts and negative perioperative localization studies for insulinoma, but positive selective arterial calcium stimulation tests and nesidioblastosis in the gradient-guided resected pancreas, is a rare hypoglycaemic disorder of undetermined aetiology. We analysed the clinical, morphological and immunohistological features to further clarify the aetiology and pathogenesis of this rare disease.

PATIENTS

Ten consecutive patients with NIPHS (nine men and one woman, aged 29-78 years) were included in the study. Six of the 10 received a gradient-guided subtotal (70%) or distal (50%) pancreatectomy. In the remaining four patients, diazoxide treatment was initiated and the precise mechanism of its action was assessed by meal tests.

RESULTS

All of the patients showed a combination of postprandial neuroglycopaenia, negative prolonged fasts (except one patient) and negative localization studies for insulinoma, but positive calcium stimulation tests and nesidioblastosis in the gradient-guided resected pancreas. Immunohistological studies of the resected pancreatic tissues revealed neither an increased rate of proliferation of beta-cells nor an abnormal synthesis and/or processing of either proinsulin or amylin. Evidence of overexpression of the two pancreatic differentiation factors, PDX-1 and Nkx-6.1, as well as the calcium sensing receptor (CaSR) was absent. Nevertheless, abnormal expression of islet neogenesis-associated protein (INGAP), a human cytokine expressed only in the presence of islet neogenesis, in ducts and/or islets, was identified in three of the five patients studied. All of the six patients who received a surgical operation were relieved of further neuroglycopaenic attacks, but one patient who received a subtotal pancreatectomy developed diabetes. In the remaining four patients who received diazoxide treatment, hypoglycaemic episodes were satisfactorily controlled with an attenuated response of beta-cell peptides to meal stimulation.

CONCLUSIONS

Our results strengthen the existence of this unique clinical hypoglycaemic syndrome from beta-cell hyperfunction as well as the value of the selective arterial calcium stimulation test in its correct diagnosis and localization. The mechanisms underlying beta-cell hyperfunction and release of insulin to calcium, however, remain poorly characterized. Nevertheless, in a subset of patients with NIPHS, there exists some, as yet undefined, pancreatic humoral/paracrine factor(s) other than proinsulin, amylin, PDX-1, Nkx-6.1 and possibly glucagon-like peptide-1 (GLP-1) that are capable of inducing the INGAP gene and, if activated, will initiate ductal proliferation and islet neogenesis. As for the treatment, we recommend that diazoxide be tried first in each patient and, should it fail, a gradient-guided subtotal or distal pancreatectomy be attempted.

The diagnosis of ectopic focal hyperinsulinism of infancy with [18F]-dopa positron emission tomography

BACKGROUND

Congenital hyperinsulinism (CHI) is a cause of severe hypoglycemia in the neonatal and infancy period. Histologically, there are two subtypes with diffuse and focal disease. The preoperative differentiation of these two forms is very important because the surgical management is radically different. The focal form of the disease can be cured if the focal lesion can be localized accurately and completely resected with surgery.

AIM

We report the case of a child who underwent three pancreatectomies with a choledochoduodenostomy and a cholecystectomy but continued to have severe hyperinsulinemic hypoglycemia.

METHODS/RESULTS

Radiological investigations including imaging with (18)fluoro-L-Dopa positron emission tomography scan showed a clear focus of increased (18)F-fluoro-L-Dopa uptake in the vicinity of the former head of the pancreas. On the magnetic resonance imaging scan, this focal uptake appeared to localize adjacent or next to duodenum (in the wall or cavity of the duodenum).

CONCLUSIONS

This unique case highlights the importance of correctly localizing and completely resecting the focal lesion in patients with CHI. (18)Fluoro-L-Dopa positron emission tomography scan can identify ectopic focal lesions in patients with CHI.

Hiperinsulinismo congénito. Revisión de 22 casos

INTRODUCTION

Congenital hyperinsulinism (CHI) is the most common cause of recurrent episodes of hypoglycemia in early childhood and consists of a group of distinct genetic disorders causing dysregulation of insulin secretion.

OBJECTIVE

To review the presentation, management and outcome of patients with CHI attended at our hospital.

MATERIAL AND METHODS

A retrospective review of all patients diagnosed with CHI between 1982 and 2004 was performed. Data were collected on age, gender, clinical presentation, medical and surgical management, and complications.

RESULTS

Twenty-two patients were identified. Notable features were early symptom onset in 80 %, pancreatectomy in 72 %, and neurological sequels in 28 % (abnormal neurodevelopment in 22 % and epilepsy in 13 %).

CONCLUSIONS

The presentation, management and outcome in our patients were similar to those in other series, indicating the need for early diagnosis and treatment to avoid neurological sequels.

Congenital hyperinsulinism

Congenital hyperinsulinism is a cause of persistent hypoglycaemia in the neonatal period. It is a heterogeneous disease with respect to clinical presentation, molecular biology, genetic aetiology and response to medical therapy. The clinical heterogeneity may range from severe life-threatening disease to very mild clinical symptoms. Recent advances have begun to clarify the molecular pathophysiology of this disease, but despite these advances treatment options remain difficult and there are many long-term complications. So far mutations in five different genes have been identified in patients with congenital hyperinsulinism. Most cases are caused by mutations in genes coding for either of the two subunits of the beta-cell K(ATP) channel (ABCC8 and KCNJ11). Two histological subtypes of the disease - diffuse and focal - have been described. The preoperative histological differentiation of these two subtypes is now mandatory as surgical management will be radically different. The ability to distinguish diffuse from focal lesions has profound implications for therapeutic approaches, prognosis and genetic counselling.

Angiography and arterial stimulation venous sampling in the localization of pancreatic neuroendocrine tumours

Insulin- and gastrin-secreting neuroendocrine tumours of the pancreas are often very small at presentation because of the potent effects of their hormonal outputs, and they may therefore prove difficult to localize preoperatively. This is despite the advances made in recent years in cross-sectional imaging techniques, especially multidetector-row computed tomography and endoscopic ultrasound. In this chapter the techniques of angiography and arterial stimulation venous sampling used for the localization of these neoplasms are described; a combination of these two modalities provides both anatomical and functional data that are not available with other localization techniques, thereby improving operative outcome.

From congenital hyperinsulinism to diabetes mellitus: the role of pancreatic beta-cell KATP channels

Pancreatic beta-cell adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channels play a pivotal role in linking glucose metabolism to regulated insulin secretion. K(ATP) channels are hetero-octameric complexes comprising two subunits Kir6.2 and sulfonylurea receptor 1 (SUR1). Changes in the intracellular concentration of nucleotides (ATP) cause alterations in the resting and opening state of the K(ATP) channels. Loss-of-function mutations in the genes encoding the two subunits of K(ATP) channels lead to the most common form of congenital hyperinsulinism (CHI). This causes persistent and severe hypoglycemia in the neonatal and infancy period. CHI can cause mental retardation and epilepsy if not treated properly. On the other hand, now there is evidence of an association between polymorphisms in the Kir6.2 gene and type 2 diabetes mellitus, mutations in the Kir6.2 gene and neonatal diabetes mellitus, and mutations in the SUR1 gene and diabetes mellitus. Interestingly, for reasons that are unclear at present, mice knockout models of K(ATP) channels are different from the human phenotype of CHI. This article is a review focusing on how abnormalities in the pancreatic beta-cell K(ATP) channels can lead to severe hypoglycemia on the one hand and diabetes mellitus on the other.

Nesidioblastosis: An Old Term and a New Understanding

Nesidioblastosis is a clinically, pathologically, and genetically heterogeneous disease. Differences between well described forms in neonates with persistent hyperinsulinemic hypoglycemia of infancy (PHHI) and rare forms in adults are described. Histopathologic criteria include hypertrophic islets occasionally showing beta cells with pleomorphic nuclei, ductuloinsular complexes, and neoformation of islets from ducts. These changes can be found as diffuse or focal forms of nesidioblastosis. Although most cases occur sporadically, several genetic defects ( SUR1, Kir6.2, GCK, and GLUD1 genes) have been described in neonates. In adults a higher rate of nesidioblastosis is observed in conjunction with multiple endocrine neoplasia type 1. The disease is diagnosed biochemically by a supervised fasting test in adults and in neonates by determining the glucose requirements to maintain normoglycemia, inappropriately high insulin and c-peptide levels, low free fatty acid and ketone body concentrations, glycemic response to glucagons, and the absence of ketonuria. If all highly selective noninvasive imaging techniques fail to identify a tumor, selective arterial calcium stimulation testing for gradient-guided surgery in adults and percutaneous transhepatic pancreatic venous sampling in neonates should be performed. a 95% pancreatectomy is necessary in neonates with a diffuse form of nesidioblastosis, whereas focal forms can be treated by partial pancreatectomy.

Hyperinsulinaemic hypoglycaemia in infancy and childhood--resolving the enigma

Children with severe hypoglycaemia due to persistent hyperinsulinism in infancy (HI) generate some of the most formidable problems of management in contemporary paediatric endocrinology. Until recently its pathophysiology was an enigma, although it was thought to be due to an anatomical abnormality in the islets of Langerhans (so called 'nesidioblastosis'). During the last 6 years there has been an explosion of knowledge providing fundamental insights into the pathological mechanisms underpinning the abnormal insulin secretion. This knowledge has been facilitated by ENRHI, a programme of research funded by the European Union, which brings together clinicians and basic scientists from 14 different countries. This collaboration encompasses clinical paediatric endocrinology, intracellular biochemistry, membrane physiology and molecular biology. This collaboration has resulted in numerous publications generating new insights into the pathophysiology of HI and represents a paradigm for collaboration in paediatric endocrinology. This review article is based on a plenary lecture delivered at the European Society for Paediatric Endocrinology meeting in Montreal on behalf of the European Network for Research into Hyperinsulinism of Infancy (ENRHI).

Hyperinsulinism in Infancy: From Basic Science to Clinical Disease

Dunne, Mark J., Karen E. Cosgrove, Ruth M. Shepherd, Albert Aynsley-Green, and Keith J. Lindley. Hyperinsulinism in Infancy: From Basic Science to Clinical Disease. Physiol Rev 84: 239–275, 2004; 10.1152/physrev.00022.2003.—Ion channelopathies have now been described in many well-characterized cell types including neurons, myocytes, epithelial cells, and endocrine cells. However, in only a few cases has the relationship between altered ion channel function, cell biology, and clinical disease been defined. Hyperinsulinism in infancy (HI) is a rare, potentially lethal condition of the newborn and early childhood. The causes of HI are varied and numerous, but in almost all cases they share a common target protein, the ATP-sensitive K+channel. From gene defects in ion channel subunits to defects in β-cell metabolism and anaplerosis, this review describes the relationship between pathogenesis and clinical medicine. Until recently, HI was generally considered an orphan disease, but as parallel defects in ion channels, enzymes, and metabolic pathways also give rise to diabetes and impaired insulin release, the HI paradigm has wider implications for more common disorders of the endocrine pancreas and the molecular physiology of ion transport.

Metabolic effects of a corticosteroid-free immunosuppressive regimen in recipients of pancreatic transplant

BACKGROUND

A corticosteroid (CS)-free immunosuppressive regimen may be considered less diabetogenic than treatments including CSs principally after pancreas transplantation.

METHODS

To test whether a CS-free immunosuppressive treatment is metabolically superior to a regimen including CSs, we prospectively studied 19 CS-free simultaneous pancreas and kidney (SPK) transplant recipients (body mass index=22+/-1 kg/m2; cyclosporine dose=400+/-19 mg/kg/day; azathioprine dose=77+/-8 mg/day; basal plasma C-peptide=1.3+/-0.12 ng/mL) and 12 matched CS-treated SPK transplant recipients (prednisone dose=9+/-1 mg/day; basal C-peptide=2.2+/-0.2 ng/mL) by means of the 6,6-2H(2)-glucose infusion and the euglycemic insulin clamp (1 mU/kg/min, insulin infusion rate). In addition, six renal transplant recipients receiving a CS-free regimen were also studied as a control group.

RESULTS

In the postabsorptive state, CS-treated SPK transplant recipients demonstrated comparable plasma glucose levels but higher plasma insulin levels than CS-free SPK transplant recipients. Plasma triglyceride levels were significantly higher in CS-treated SPK patients than in CS-free SPK patients (1.16+/-0.16 mg/dL vs. 0.88+/-0.08; P<0.05). High-density lipoprotein and apoprotein A(1) levels were similar in both groups. No difference was observed in pyruvate, lactate, beta-OH-butyrate, and basal endogenous glucose production in all three groups of patients studied. During euglycemic hyperinsulinemia, the inhibition of endogenous glucose production and the stimulation of tissue glucose disposal were not statistically different among the three groups.

CONCLUSIONS

SPK recipients receiving chronic low-dose CS maintenance therapy do not present a lower glucose disposal than CS-free recipients. Nonetheless, this is obtained at the expense of a higher endogenous insulin secretion, which can cause an alteration of the triglyceride profile.

Surgery of persistent hyperinsulinaemic hypoglycaemia

Hyperinsulinism (HI) is the commonest cause of persistent or recurrent hypoglycaemia in childhood. HI is genetically and phenotypically diverse. Key management issues involve early diagnosis by insuring that appropriate investigations are undertaken at the point of hypoglycaemia, prevention of recurrent hypoglycaemia and clinical, biochemical and genetic characterisation of the HI syndrome. Children with persistent diazoxide resistant HI require investigation at specialist centres to differentiate those with a generalised disorder of the pancreas (diffuse HI; di-HI) from those with localised abnormalities within the pancreas (focal HI; fo-HI). Fo-HI may be managed by selective pancreatic resection of the focal abnormality. Di-HI is only managed by surgery if combination drug therapies are unable to prevent hypoglycaemia. Pancreatic beta-cell dysfunction persists following subtotal pancreatectomy of di-HI.

Focal or diffuse lesions in persistent hyperinsulinemic hypoglycemia of infancy: concerns about interpretation of intraoperative frozen sections

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) results from defects of regulated insulin release from pancreatic beta cells and is often refractory to medical treatment. Histological changes in the pancreas associated with PHHI may be focal or diffuse, and the intraoperative confirmation and siting of focal lesions would require frozen section diagnosis. The recognition of focal involvement and its distinction from diffuse disease by frozen section depends on the identification and distribution pattern of islet cells with large hyperchromatic nuclei. This study was designed to test the feasibility of using this parameter in PHHI to delineate focal from diffuse diseases prior to the introduction of frozen sections to guide intraoperative management in our institution. A total of 66 coded and randomized paraffin sections (from 18 PHHI and 4 postmortem pancreases) were scored by three independent observers into the following categories: a focal lesion (A), no large endocrine nuclei (B), few large endocrine nuclei (C), and frequent large endocrine nuclei (D). Interobserver concordance was complete in 88%, but there were minor discrepancies in the remaining 12%. When a focal lesion was present in one section no large endocrine nuclei were seen in sections from the rest of the pancreas. In four patients with diffuse PHHI, no or only very scanty large endocrine nuclei were seen. From this finding, and the observation that in other examples of diffuse disease, large endocrine nuclei were sparse even in large paraffin sections, we have reservations about using small frozen sections for reliable diagnosis.

Calcium-stimulated insulin secretion in diffuse and focal forms of congenital hyperinsulinism

OBJECTIVES

To identify infants with hyperinsulinism caused by defects of the beta-cell adenosine triphosphate-dependent potassium channel complex and to distinguish focal and diffuse forms of hyperinsulinism caused by these mutations.

STUDY DESIGN

The acute insulin response to intravenous calcium stimulation (CaAIR) was determined in 9 patients <20 years with diffuse hyperinsulinism caused by defective beta-cell sulfonylurea receptor (SUR1(-/-)), 3 patients with focal congenital hyperinsulinism (6 weeks to 18 months), a 10-year-old with insulinoma, 5 with hyperinsulinism/hyperammonemia syndrome caused by defective glutamate dehydrogenase (6 months to 28 years), 4 SUR1(+/-) heterozygotes with no symptoms, and 9 normal adults. Three infants with congenital focal disease, 1 with diffuse hyperinsulinism, and the child with insulinoma underwent selective pancreatic intra-arterial calcium stimulation with hepatic venous sampling.

RESULTS

Children with diffuse SUR1(-/-) disease and infants with congenital focal hyperinsulinism responded to CaAIR, whereas the normal control group, patients with hyperinsulinism/hyperammonemia syndrome, and SUR1(+/-) carriers did not. Selective arterial calcium stimulation of the pancreas with hepatic venous sampling revealed selective, significant step-ups in insulin secretion that correlated anatomically with the location of solitary lesions confirmed surgically in 2 of 3 infants with congenital focal disease and in the child with insulinoma. Selective arterial calcium stimulation of the pancreas with hepatic venous sampling demonstrated markedly elevated baseline insulin levels throughout the pancreas of the infant with diffuse hyperinsulinism.

CONCLUSIONS

The intravenous CaAIR is a safe and simple test for identifying infants with diffuse SUR1(-/-) hyperinsulinism or with focal congenital hyperinsulinism. Preoperative selective arterial calcium stimulation of the pancreas with hepatic venous sampling can localize focal lesions causing hyperinsulinism in children. The combination of these calcium stimulation tests may help distinguish focal lesions suitable for cure by local surgical resection.

The calcimimetic R-467 potentiates insulin secretion in pancreatic beta cells by activation of a nonspecific cation channel

The extracellular, G protein-linked Ca(2+)-sensing receptor (CaSR), first identified in the parathyroid gland, is expressed in several tissues and cells and can be activated by Ca(2+) and some other inorganic cations and organic polycations. Calcimimetics such as NPS (R)-N-(3-phenylpropyl)-alpha-methyl-3-methoxybenzylamine hydrochloride (R-467), a phenylalkylamine, are thought to activate CaSR by allosterically increasing the affinity of the receptor for Ca(2+). When tested for its effect on insulin release in C57BL/6 mice, R-467 had no effect under basal conditions but enhanced both phases of glucose-stimulated release. The betaHC9 cell also responded to R-467 and to the enantiomer S-467 with a stimulation of insulin release. In subsequent studies with the betaHC9 cell, it was found that the stimulatory effect was due to activation of a nonspecific cation channel, depolarization of the beta-cell, and increased Ca(2+) entry. No other stimulatory mechanism was uncovered. The depolarization of the cell induced by the calcimimetic could be due to a direct action on the channel or via the CaSR. However, it appeared not to be mediated by G(i), G(o), G(q/11), or G(s). The novel mode of action of the calcimimetic, combined with the glucose-dependence of the stimulation on islets, raises the possibility of a totally new class of drugs that will stimulate insulin secretion during hyperglycemia but which will not cause hypoglycemia.

Practical management of hyperinsulinism in infancy

Hyperinsulinism in infancy is one of the most difficult problems to manage in contemporary paediatric endocrinology. Although the diagnosis can usually be achieved without difficulty, it presents the paediatrician with formidable day to day management problems. Despite recent advances in understanding the pathophysiology of hyperinsulinism, the neurological outcome remains poor, and there is often a choice of unsatisfactory treatments, with life long sequelae for the child and his or her family. This paper presents a state of the art overview on management derived from a consensus workshop held by the European network for research into hyperinsulinism (ENRHI). The consensus is presented as an educational aid for paediatricians and children's nurses. It offers a practical guide to management based on the most up to date knowledge. It presents a proposed management cascade and focuses on the clinical recognition of the disease, the immediate steps that should be taken to stabilise the infant during diagnostic investigations, and the principles of definitive treatment.

Hyperinsulinemic hypoglycemia of infancy. Recent insights into ATP-sensitive potassium channels, sulfonylurea receptors, molecular mechanisms, and treatment

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI), previously termed "nesidioblastosis," is an important cause of hypoglycemia in infancy and childhood. Recent studies have defined this syndrome at the molecular, genetic, and clinical level. This article reviews the genetic and molecular basis of these entities, describes their clinical manifestations, and discusses the rationales for available therapeutic options.