Nesidioblastosis and Subsequent Diabetes Mellitus in a Dog with Hyperinsulinemic Hypoglycemia Treated with Partial Pancreatectomy.

A 6.5 yr old castrated male mixed-breed dog was presented for clinical signs associated with hypoglycemia. Hyperinsulinemic hypoglycemia was diagnosed as the cause of the persistent hypoglycemia. No obvious pancreatic mass was seen on abdominal computed tomography and exploratory laparotomy. A partial pancreatectomy was performed with the suspicion of an insulinoma-causing hyperinsulinemic hypoglycemia. Nesidioblastosis was diagnosed based clinical, biochemical, and histopathologic findings. There was beta cell hyperplasia and no evidence of neoplasia. The dog was euglycemic postoperatively after a partial pancreatectomy. Long-term follow-up after 2 yr revealed that the dog was diagnosed with diabetes mellitus.

Circularity of islets is a distinct marker for the pathological diagnosis of adult non-neoplastic hyperinsulinemic hypoglycemia using surgical specimens.

BACKGROUND: Adult non-neoplastic hyperinsulinemic hypoglycemia (ANHH), also known as adult-onset nesidioblastosis, is a rare cause of endogenous hyperinsulinemic hypoglycemia in adults. This disease is characterized by diffuse hyperplasia of pancreatic endocrine cells and is diagnosed by a pathological examination. While diagnostic criteria for this disease have already been proposed, we established more quantitative criteria for evaluating islet morphology. METHODS: We measured the number, maximum diameter, total area, and circularity (representing how closely islets resemble perfect spheres) of islets contained in representative sections of ANHH (n = 4) and control cases (n = 5) using the NIS-Elements software program. We also measured the average cell size, percentage of cells with enlarged nuclei, and percentage of cells with recognizable nucleoli for each of three representative islets. We also assessed the interobserver diagnostic concordance of ANHH between five experienced and seven less-experienced pathologists. RESULTS: There was no significant difference in the number, maximum diameter, or total area of islets between the two groups, even after correcting for these parameters per unit area. However, the number of islets with low circularity (< 0.71) per total area of the pancreatic parenchyma was significantly larger in ANHH specimens than in controls. We also found that the percentage of cells with recognizable nucleoli was significantly higher in the ANHH group than in the controls. There were no significant differences in the average cell size or the number of cells with enlarged nuclei between the groups. The correct diagnosis rate with the blind test was 47.5% ± 6.12% for experienced pathologists and 50.0% ± 8.63% for less-experienced pathologists, with no significant differences noted. CONCLUSIONS: Low circularity, which indicates an irregular islet shape, referred to as "irregular shape and occasional enlargement of islets" and "lobulated islet structure" in a previous report, is a useful marker for diagnosing ANHH. An increased percentage of recognizable nucleoli, corresponding to "macronucleoli in ß-cells," has potential diagnostic value.

Pathological features in non-neoplastic congenital and adult hyperinsulinism: from nesidioblastosis to current terminology and understanding.

Nesidioblastoma and nesidioblastosis were terms given to neoplastic and non-neoplastic lesions of the pancreas associated with pancreatogenous hyperinsulinaemic hypoglycaemia. While nesidioblastoma was rapidly replaced by islet cell tumour, nesidioblastosis, defined as the proliferation of islet cells budding off from pancreatic ducts, was the diagnostic term associated with congenital hyperinsulinism of infancy (CHI) and adult non-neoplastic hyperinsulinaemic hypoglycaemia (ANHH). When it was shown that nesidioblastosis was not specific for CHI or ANHH, it was no longer applied to CHI but kept for the morphological diagnosis of ANHH. In severe CHI cases, a diffuse form with hypertrophic ß-cells in all islets can be distinguished from a focal form with hyperactive ß-cells changes in a limited adenomatoid hyperplastic area. Genetically, mutations were identified in several ß-cell genes involved in insulin secretion. Most common are mutations in the ABCC8 or KCNJ11 genes, solely affected in the diffuse form and associated with a focal maternal allelic loss on 11p15.5 in the focal form. Focal CHI can be localized by 18F-DOPA-PET and is thus curable by targeted resection. Diffuse CHI that fails medical treatment requires subtotal pancreatectomy. In ANHH, an idiopathic form can be distinguished from a form associated with gastric bypass, in whom GLP1-induced stimulation of the ß-cells is discussed. While the ß-cells in idiopathic ANHH are diffusely affected and are either hypertrophic or show only little changes, it is controversial whether there is a ß-cell increase or ß-cell hyperactivity in patients with gastric bypass. Recognizing morphological signs of ß-cell hyperactivity needs a good knowledge of the non-neoplastic endocrine pancreas across all ages.

Nesidioblastosis and Insulinoma: A Rare Coexistence and a Therapeutic Challenge.

Background: Nesidioblastosis and insulinoma are disorders of the endocrine pancreas causing endogenous hyperinsulinemic hypoglycemia. Their coexistence is very unusual and treatment represents a still unresolved dilemma. Case Description: The patient was a 43-year-old Caucasian woman, with a 2-year history of repeated severe hypoglycemic events. The diagnostic work-up was strongly suggestive of insulinoma and the patient was submitted to surgical treatment carried out laparoscopically under robotic assistance. However, surgical exploration and intraoperative ultrasonography failed to detect a pancreatic tumor. Resection was therefore carried out based on the results of selective intra-arterial calcium stimulation test, following a step-up approach, eventually leading to a pancreatoduodenectomy at the splenic artery. The histopathology examination and the immunohistochemical staining were consistent with adult-onset nesidioblastosis. After surgery, the patient continued to experience hypoglycemia with futile response to medical treatments (octreotide, calcium antagonists, diazoxide, and prednisone). Following multidisciplinary evaluation and critical review of a repeat abdominal computed tomography scan, a small nodular lesion was identified in the tail of the pancreas. The nodule was enucleated laparoscopically and the pathological examination revealed an insulinoma. In spite of the insulinoma resection, glycemic values were only partially restored, with residual nocturnal hypoglycemia. Administration of uncooked cornstarch (1.25 g/kg body weight) at bedtime was associated with significant improvement of interstitial glucose levels (p < 0.0001) and reduction of nocturnal hypoglycemia episodes (p = 0.0002). Conclusions: This report describes a rare coexistence of adult-onset nesidioblastosis and insulinoma, suggesting the existence of a wide and continuous spectrum of proliferative ß-cell changes. Moreover, we propose that uncooked cornstarch may offer an additional approach to alleviate the hypoglycemic episodes when surgery is impracticable/unaccepted.

Concurrent Adult-Onset Diffuse ß-Cell Nesidioblastosis and Pancreatic Neuroendocrine Tumor: A Case Report and Review of the Literature.

Nesidioblastosis is an uncommon cause of organic persistent hyperinsulinemic hypoglycemia in adults. We report a case of adult-onset diffuse ß-cell nesidioblastosis in a 49-year-old woman who was status-post Roux-en-Y gastric bypass and distal pancreatectomy for a well-differentiated pancreatic neuroendocrine tumor. While the neuroendocrine tumor was suspected to be an insulinoma, persistent hypoglycemia postoperatively suggested either incomplete resection or a second pancreatic neoplasm. Completion pancreatectomy revealed islet ß-cell hyperplasia and nuclear pleomorphism consistent with ß-cell nesidioblastosis. The patient's blood glucose levels normalized after completion pancreatectomy. While ß-cell nesidioblastosis and insulinomas can coexist in the same patient, pathologists should be aware of ß-cell nesidioblastosis as a potential cause for hyperinsulinemic hypoglycemia and should exclude it in patients who have not shown definitive clinical response after surgical excision of a pancreatic neuroendocrine tumor.

Masa pancreática: una presentación inhabitual de nesidioblastosis en el adulto / Pancreatic mass: an unusual presentation of nesidioblastosis in adults

A 41-year-old woman, multiparous of 4, with personal or familiar history of diabetes, with a history of Nissen fundoplication due to pathological gastro-oesophageal reflux, is refer to an endocrinologjst during her post-operatiye follow up, 4 months after her surgery for a 14 kg weight loss in 10 months and symtomatic hypoglycemia to repetition. A positive prolonged fasting test for hypoglycemia was performed. In addition, abdominal computed axial tomography was performed, which resulted normal and endosonography, showing a lesion on the head of the pancreas. Octreoscan positive for pancreatic head focal lesion with positive somatostatin receptors compatible with insulinoma. Whipple surgery was performed where surgeon palpated pancreatic tumor, biopsy showed tissue compatible with diffuse nesidioblastosis. In the postoperative period, the patient decreased frequency and intensity of hypoglycemic episodes compared to their previous stage. Control prolonged fasting test and Octreoscan were within normal ranges. However, 4 months after surgery, the patient presented hypoglycemia of lower intensity and frequency than before surgery. Currently he remains in control with nutritionist and endocrinologist, mainly adjusting diet and with good control glycemias.

Anaesthetic Management Of Nesidioblastosis In Two Infants.

Nesidioblastosis is the most common cause of non-transient, recurrent and persistent hypoglycaemia in neonates and infants. It is a disorder of diffuse proliferation of beta cells of the pancreas leading to hyperinsulinemia and hypoglycaemia. The main aim is to prevent the severe episodes of hypoglycaemia which can cause damage to the brain and/or mental retardation. In this case report we present two cases of nesidioblastosis and their perioperative anaesthetic course for near-total pancreatectomy. First case was a 7 months old female who had repeated episodes of convulsions since birth. Second case was a 4-month-old female child who again presented with seizures. The challenges faced in the perioperative period were the management of perioperative blood glucose levels and haemodynamic stability.

Robotic Near-Total Pancreatectomy for Nesidioblastosis after Bariatric Surgery.

Postprandial symptoms of neuroglycopenia after bariatric surgery may result as a consequence of endogenous hyperinsulinemic hypoglycemia (nesidioblastosis) not dumping syndrome. Pancreatectomy is an acceptable treatment for this condition. We present the video of a case of near-total distal robotic pancreactectomy for the treatment of nesidioblastosis after Roux-en-Y gastric bypass. Robotic pancreatectomy is an alternative to the treatment of nesidioblastosis after Roux-en-Y gastric bypass.

Intraoperative portal vein insulin assay combined with occlusion of the pancreas for complex pancreatogenous hypoglycemia: Two cases report.

Intraoperative localization and confirmation of complete resection of the hypersecreting tissue are the 2 main challenges in the management of pancreatogenous hypoglycemia. Here, we report our experience with intraoperative portal vein insulin assay combined with occlusion of the pancreas in the management of pancreatogenous hypoglycemia. Clinical courses of 2 patients with biochemical evidence of a pancreatogenous hypoglycemia were studied. The preoperative diagnosis was multiple endocrine neoplasia 1 (MEN-1) and nesidioblastosis, respectively. Rapid intraoperative portal vein insulin assay combined with occlusion of the pancreas was used to localize and confirm complete excision of the hypersecreting tissue. Hypoglycemia was successfully treated in both the patients. In the MEN-1 patient, 2 small tumors in the head of pancreas were not resected, as they were deemed noninsulin secreting by intraoperative portal vein insulin assay, thus avoiding a total pancreatectomy. In the patient with nesidioblastosis, using intraoperative portal vein insulin assay combined with occlusion of the pancreas, an appropriate amount of pancreatic tissue was resected thereby avoiding recurrence and diabetes. This technique may be of particular value in patients with complex conditions such as MEN-1 and nesidioblastosis, to localize and achieve complete resection of hypersecreting pancreatic tissue.

Synchronous Nesidioblastosis, Endocrine Microadenoma, and Intraductal Papillary Mucinous Neoplasia in a Man Presenting With Hyperinsulinemic Hypoglycemia.

Herein, we report the first case of concomitant nesidioblastosis, pancreatic neuroendocrine tumor, and intraductal papillary mucinous neoplasia. The combination is significant as each of these pathological entities is independently very rare. The patient was a 33-year-old man who presented with symptomatic hyperinsulinemic hypoglycemia and no risk factors for pancreatic disease. Abdominal imaging showed an isolated 12 mm pancreatic lesion, whilst selective arterial calcium stimulation testing demonstrated multiple territories of insulin excess. He proceeded to subtotal pancreatectomy. Histopathology revealed an endocrine microadenoma, α and ß cell nesidioblastosis, and multifocal intraductal papillary mucinous neoplasia. The endocrine microadenoma and nesidioblastosis stained for insulin, suggesting both likely contributed to hypoglycemia. Glucagon immunohistochemistry was also positive, though there were no clinical features of glucagon excess. Hypoglycemia resolved postoperatively. This case and other evidence from the literature suggest that hyperplasia and neoplasia may occur sequentially in the pancreas, and that endocrine and exocrine tumorigenesis may be linked in some individuals. Further study is required to identify a unifying mechanism, and to elucidate potential ramifications in the management of patients with pancreatic neoplasms.

Selective Arterial Calcium Stimulation With Hepatic Venous Sampling Differentiates Insulinoma From Nesidioblastosis.

CONTEXT: In adult patients with endogenous hyperinsulinemic hypoglycemia and negative or inconclusive noninvasive imaging, insulinoma and non-insulinoma pancreatogenous hypoglycemic syndrome (NIPHS) resulting from diffuse nesidioblastosis must be considered in the differential diagnosis. It is not known whether the biochemical results of selective arterial calcium stimulation (SACST) with hepatic venous sampling can differentiate insulinoma from diffuse nesidioblastosis. OBJECTIVE: To determine the specificity of SACST with hepatic venous sampling in differentiating insulinoma from diffuse nesidioblastosis. DESIGN: Retrospective review (January 1996 to March 2014). SETTING: Tertiary referral center. PATIENTS OR OTHER PARTICIPANTS: A total of 116 patients with biochemical evidence of endogenous hyperinsulinemic hypoglycemia and negative or inconclusive noninvasive imaging who were subsequently shown at surgery to have insulinoma (n = 42) or nesidioblastosis (n = 74) after undergoing SACST with hepatic venous sampling. INTERVENTION(S): SACST with hepatic venous sampling before pancreatic exploration. MAIN OUTCOME MEASURE(S): Receiver operating characteristic curves were generated from the biochemical results of SACST to determine the specificity of the maximum hepatic venous insulin concentration (mHVI) and the relative-fold increase in hepatic venous insulin concentration (rHVI) over baseline after calcium injection from the dominant artery in differentiating insulinoma from nesidioblastosis. RESULTS: The mHVI (21.5-fold; P < .001) and rHVI (3.9-fold; P < .001) were significantly higher in the insulinoma group compared to the nesidioblastosis group. The areas under the receiver operating characteristic curve for mHVI and rHVI were excellent (0.94; P < .0001) and good (0.83; P < .0001), respectively, for differentiating insulinoma from nesidioblastosis. mHVI cutoffs of > 91.5 and > 263.5 µIU/mL were 95 and 100% specific for insulinoma, respectively. A 19-fold increase in rHVI over baseline was 99% specific for insulinoma. CONCLUSIONS: These data suggest that the mHVI and rHVI at SACST may be useful in differentiating insulinoma from nesidioblastosis with high specificity in patients with hyperinsulinemic hypoglycemia and negative or inconclusive noninvasive imaging.

Pathological aspects underlying pancreatogenous hyperinsulinemic hypoglycemia--report of three cases.

Pancreatogenous hyperinsulinemic hypoglycemia (PHH) is a rare disorder determined by an abnormally high secretion of insulin in the pancreas, in the absence of other medical or pharmacological factors. Either ß-cell tumors (insulinomas) or ß-cell hyperplasia (nesidioblastosis) can determine this pathology. Most publications on insulinomas or nesidioblastosis approached these subjects from a clinical point of view. This paper aims to analyze pathological aspects underlying pancreatogenous hyperinsulinemic hypoglycemia. We present two cases of insulinomas with unusual pancreatic localization and size, one of them showing amyloid deposits in the stroma. In both cases, immunohistochemistry confirmed the clinical and imagistic supposition. The third reported case refers to a 57-year-old patient with nesidioblastosis with isolated disposition of endocrine cells and areas of focal organization, both morphological aspects being extremely rare in adults. Although clinical and laboratory data are usually identical in the two forms of PHH, histopathological and immunohistochemical diagnosis is essential in differentiating insulinomas from nesidioblastosis, as the surgical management is different: enucleation for insulinomas and total or subtotal pancreatectomy for nesidioblastosis.

Refractory hypoglycaemia in patient with gastric outlet obstruction.

A 68-year-old male with a longstanding history of severe gastric outlet obstruction secondary to peptic stricture was found unconscious at home with profound hypoglycaemia. He denied history of fasting, diabetes mellitus or use of hypoglycaemic agents. Systemic examination and metabolic profile were unremarkable. Hypoglycaemic episodes persisted during hospitalisation, requiring continuous intravenous dextrose and eventually diazoxide. Further investigative work up, including 72 h fasting study, revealed a hyperinsulinemic state. MRI and endoscopic ultrasound were unremarkable but mesenteric angiography with hepatic venous sampling revealed a subtle area of hypervascularity in the head of pancreas. An exploratory laparotomy was then performed and resulted in resection of a nodular lesion in the head of pancreas with retrocolic gastrojejunostomy for repair of pyloric stenosis. Histopathology of pancreatic nodule confirmed nesidioblastosis. Postoperatively the patient was weaned of parenteral dextrose and did not have any further episodes of hypoglycaemia.

A rare complication of gastric bypass (weight loss) surgery: nesidioblastosis.

Here, we present the case of a 31-year-old woman patient who underwent distal pancreatectomy with the history of gastric bypass surgery for obesity. The final histopathological diagnosis of the lesion was nesidioblastosis. Nesidioblastosis is the most common cause of organic persistent hyperinsulinemic hypoglycemia in newborns; however, it is rare in adults. In adults, it is difficult to diagnose nesidioblastosis with only clinical findings. The definitive diagnosis of the disease depends on the histopathological examination of pancreatic tissue and the exclusion of insulinoma.

Postprandial hyperinsulinemic hypoglycemia after gastric bypass surgical treatment.

An association between post-Roux-en-Y gastric bypass (RYGB) hypoglycemia and nesidioblastosis was reported in 2005 and may cause serious neuroglycopenic symptoms. Most patients with postprandial hypoglycemia after RYGB respond to nutritional and medical treatment. A subset of patients, however, may not respond adequately and surgery may be considered. This review describes the current experience with surgical intervention for severe post-RYGB hypoglycemia. PubMed and MEDLINE searches were made for reports describing clinical outcome after such surgery. Fourteen papers including 75 patients were identified. Different surgical interventions were applied including gastric tube placement, reversal of the bypass with and without concomitant sleeve resection, gastric pouch restriction, and pancreatic resection and reresection. Pancreatic resection was performed in 51 (68%) patients, 17 (23%) had RYGB reversal and eleven (15%) had gastric pouch restriction alone. Eight (11%) patients received 2 or more consecutive procedures for hypoglycemia and combined interventions were made in several patients. Resolution of the symptoms occurred in 34/51 (67%) patients after pancreatic resection, 13/17 (76%) after reversal, and 9/11 (82%) after pouch restriction. Mean follow up, however, was short for most series and the methods applied for evaluation of hypoglycemia varied. Weight regain, diabetes and recurrent symptoms were late complications. The optimal therapy for hypoglycemia after RYGB is not defined. Long-term evaluations and knowledge about the physiology of post-RYGB hypoglycemia, may enable therapy with improved control of the glucose excursions.

Nesidioblastosis. A case of hyperplasia of the islets of Langerhans in the adult.

INTRODUCTION: Nesidioblastosis is a rare disease caused by hyperplasia of pancreatic islets, developing a state of hypoglycemia due to an increase in the insulin production. It is the leading cause of hyperinsulinic hypoglycemia in childhood, whereas in adults it only represents the 0.5-5% of cases. The pathogenesis is still unknown. We have studied several genetic mutations associated with dependent potassium channel of ATP present in the beta cells of the pancreas, as well as in patients underwent bariatric surgery because of the metabolic changes involved. REPORT: Woman (38 years old) attends consultation of General Surgery derived from Endocrinology before symptoms of persistent hypoglycemia. Factitious hypoglycemia and syndromes of neuroendocrine origin were ruled out. Imaging tests failed to identify space-occupying lesions. The medical treatment failed, persisting hypoglycemia symptoms. Before the given analytical and radiological findings obtained, and the persistence of symptoms affecting the quality of life of the patient, we opted for surgical treatment performing a pancreatectomy of the 80% of the gland. The final pathologic diagnosis was nesidioblastosis. DISCUSSION: Nesidioblastosis is a rare pathology, but it must be present in the differential diagnosis of hypoglycemia symptoms with endogenous hyperinsulinism in adults, once the intake of sulfonylureas and possible pancreatic neoformations have been ruled out.

Treatment of hyperinsulinemic hypoglycemia because of diffuse nesidioblastosis with nifedipine after surgical therapies in a newborn.

Recent studies have demonstrated a role for calcium channel blocking agents in the treatment of persistent hyperinsulinemic hypoglycemia of newborns. We report a newborn infant with persistent hyperinsulinemic hypoglycemia whom we successfully treated with oral nifedipine alone after surgical therapies. A 4-day-old male infant was referred with intractable hypoglycemia and seziures. Normoglycaemia could be maintained only by the intravenous infusion of glucose at a rate of 20 mg/kg per minute. Persistent hyperinsulinemic hypoglycemia of newborn was diagnosed from an inappropriately raised plasma insulin concentration (44 mU/L) at the time of hypoglycemia. Medical treatments led to only a mild reduction in the intravenous glucose requirement; an 85-90% pancreatectomy was performed and histological "diffuse nesidioblastosis" was confirmed. However, despite all the medical treatments after the first pancreatectomy, the hyperinsulinemic hypoglycemia persisted and a second 95% pancreatectomy was performed. After the second pancreatectomy, persistent hyperinsulinemic hypoglycemia was treated with somatostatin and diazoxide, but led to no reduction in the intravenous glucose requirement. We report the case of an infant who had persistent hypoglycemia after two subtotal pancreatic resections but subsequently became normoglycemic on treatment with nifedipine (2 mg/kg per day). The patient was discharged home on oral nifedipine. Calcium channel blocking agents cuold be used with efficacy and safety in recurrent persistent hyperinsulinemic hypoglycemia.

Adult onset nesidioblastosis treated by subtotal pancreatectomy.

CONTEXT: Nesidioblastosis is a rare cause of non insulinoma pancreatogenous hypoglycemic syndrome seen in adults. It is characterized by postprandial hypoglycemia with high insulin and C-peptide levels without any detectable pancreatic lesion. The definitive diagnosis can be made only on histopathological examination of the resected specimen. CASE REPORT: We report a case of a 50-year-old lady presenting with hypoglycemic attacks being misdiagnosed preoperatively as insulinoma and treated with enucleation leading to recurrence of symptoms after 6 months. Later medical therapy was tried which failed and patient needed subtotal pancreatectomy for resolution of symptoms. CONCLUSION: Nesidioblastosis should be suspected in patients with endogenous hyperinsulinemic hypoglycemia without any detectable pancreatic tumor on preoperative imaging.