Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline

Insulinoma Unmasked: A Continuous Glucose Monitoring-Fueled Journey

Insulinomas are rare functional neuroendocrine tumors that are usually indolent and small. Due to their rarity, there is often a delay in disease recognition and diagnosis, and small tumor size makes their localization challenging. Glucose monitoring and dietary modification with or without pharmacotherapy are crucial during diagnostics, and surgery is the only definite treatment. Continuous glucose monitoring (CGM) systems can be a valuable tool in managing insulinoma patients. We present three patients with confirmed endogenous hyperinsulinemic hypoglycemia undergoing tumor localization, medical treatment, and surgery while wearing a CGM system. By accurately depicting glucose fluctuations, CGM can help prevent hypoglycemia, decrease hypoglycemia unawareness, track hypoglycemia frequency, aid in medical therapy dose titration, and confirm a cure after surgery.

Glucose Disorders

Glucose disorders are the most common endocrine condition in the primary care setting. The conditions overlap and are better viewed as a spectrum rather than discrete entities. Multiple treatment agents are now available for diabetes mellitus which include long-acting and short-acting insulins and medications targeting the various pathways of diabetes including liver gluconeogenesis, increasing peripheral insulin sensitivity, stimulating pancreatic insulin production, eliminating glucose renally, decreasing carbohydrate gastrointestinal absorption, and targeting the body's incretin system. Various endocrine conditions can cause secondary hyperglycemia or hypoglycemia. Medications and physiologic stress can affect glucose levels. Genetic syndromes causing enzyme deficiencies underlie a small portion of glucose disorders.

Paraneoplastic hypoglycemia: An overview for optimal clinical guidance

Paraneoplastic hypoglycemia, also known as non-islet cell tumor hypoglycemia (NICTH), is a rare but critical condition occurring in patients with different types of malignancy. This condition is commonly linked to tumors producing insulin-like growth (IGF) factors, particularly IGF-2 and its precursors, which disrupt glucose homeostasis and lead to excessive glucose consumption. The diagnosis typically involves documenting symptomatic hypoglycemia and ruling out other potential causes. Essential diagnostic tools include imaging studies and laboratory tests, specifically measuring IGF-2 levels and the IGF-2:IGF-1 ratio. Treatment strategies for NICTH are multifaceted and may include surgical resection of the tumor if feasible, pharmacological interventions such as corticosteroids to suppress IGF-2 production, or supportive measures to manage acute hypoglycemic episodes. Novel therapeutic approaches targeting IGF-2, such as monoclonal antibodies or siRNA, are also being explored and hold promise for future treatment options. This review aims to enhance understanding of paraneoplastic hypoglycemia, focusing on its pathogenesis and diagnosis, to guide optimal medical treatment.

Hyperinsulinemic Hypoglycemia Due to an Insulinoma in a 2-Year-Old Child

Insulinomas are rare insulin-secreting tumors that most commonly affect adults. A 26-month-old child presented to her local emergency department with severe hypoglycemia. Initial workup was consistent with hyperinsulinemic hypoglycemia. Over the course of 10 months, multiple therapies for hyperinsulinism (HI) were trialed without significant benefit. Genetic testing for genes associated with HI was negative. At age 35 months, the patient was transferred to our center for further treatment. She underwent several imaging tests that revealed a lesion on her pancreas concerning for an insulinoma. The patient underwent surgical intervention to enucleate the lesion. Histopathological review of the specimen confirmed a benign, well-circumscribed insulinoma. A postoperative fasting test proved the patient was cured and she was discharged without the need for further glucose monitoring.

Spontaneous hypoglycemia: should we mind the gap? Long-term follow-up of healthy people who met Whipple's triad criteria

CONTEXT

Patients discharged as "healthy" with the symptoms of spontaneous hypoglycemia, commonly known as Whipple's triad, need more attention.

OBJECTIVE

Characterization and long-term follow-up of symptom development in patients with spontaneous hypoglycemia discharged as "healthy". The objective was to ascertain whether any conditions related to the symptoms were diagnosed during the follow-up period.

METHODS

Retrospective analysis of patient data and evaluation of a specific questionnaire on the development of symptoms of spontaneous hypoglycemia. In addition, patient questionnaires were evaluated and primary care physicians were asked about possible diseases not recorded at baseline that occurred during the follow-up period.

SETTING

Center for Endocrinology, Diabetology, and Osteology at the University Hospital Marburg, Inpatient Department, Germany.

PATIENTS

All patients who presented to our center for the 72-hour fast between 2005 and 2018 and were discharged without an internal medicine diagnosis were included.

INTERVENTIONS

Survey by questionnaire, via telephone interview.

MAIN OUTCOME MEASURES

Patient-reported information on current symptoms compared to original symptoms, diagnosis of insulinoma or diabetes mellitus during follow-up, matched with primary care physician data, and metabolic and biometric data such as body mass index (BMI), homeostasis model assessment for insulin resistance (HOMA IR), insulin sensitivity Matsuda Index (ISI-M), and area under the curve.

RESULTS

A total of 41 datasets were evaluated at baseline and 38 patients were followed for an average of approximately 10 years. In total, 61% of respondents still reported the same symptoms as at baseline. No insulinoma was missed in these patients. Only two of the 38 patients developed diabetes mellitus.

CONCLUSION

The high percentage of patients who are discharged as "healthy" and still have symptoms after many years is disturbing. It is possible that the symptoms are not due to low blood glucose. We urge caution with use of the term "healthy". We advocate a multidisciplinary therapeutic approach after an organic cause of hypoglycemia has been ruled out. Psychosomatic treatment seems to be useful. In addition, more research should be conducted on this topic.

Theragnostic utility of continuous glucose monitoring in post-gastrectomy hypoglycemia

Diagnosing post-gastrectomy hypoglycemia is challenging, often relying on medical history with documented low plasma glucose levels. Here, we present three cases of patients who presented a high probability of post-gastrectomy hypoglycemia diagnosed and managed successfully using "theragnostic" continuous glucose monitoring and alpha-glucosidase inhibitors. In the first week, patients maintained their current lifestyle without medical intervention; in the second week, voglibose 0.2 mg before meals was prescribed. Continuous glucose monitoring data from the first week confirmed the diagnosis with multiple hypoglycemic events after postprandial peaks, whereas data from the second week showed reduced hypoglycemic events and lower glycemic variability, demonstrating voglibose's therapeutic effect. This report highlights the effective management of post-gastrectomy hypoglycemia using voglibose and theragnostic continuous glucose monitoring, showing its potential benefits and safety for similar cases.

Medications that Regulate Gastrointestinal Transit Influence Inpatient Blood Glucose

Objective

A multitude of factors affect a hospitalized individual's blood glucose (BG), making BG difficult to predict and manage. Beyond medications well established to alter BG, such as beta-blockers, there are likely many medications with undiscovered effects on BG variability. Identification of these medications and the strength and timing of these relationships has potential to improve glycemic management and patient safety.

Materials and Methods

EHR data from 103,871 inpatient encounters over 8 years within a large, urban health system was used to extract over 500 medications, laboratory measurements, and clinical predictors of BG. Feature selection was performed using an optimized Lasso model with repeated 5-fold cross-validation on the 80% training set, followed by a linear mixed regression model to evaluate statistical significance. Significant medication predictors were then evaluated for novelty against a comprehensive adverse drug event database.

Results

We found 29 statistically significant features associated with BG; 24 were medications including 10 medications not previously documented to alter BG. The remaining five factors were Black/African American race, history of type 2 diabetes mellitus, prior BG (mean and last) and creatinine.

Discussion

The unexpected medications, including several agents involved in gastrointestinal motility, found to affect BG were supported by available studies. This study may bring to light medications to use with caution in individuals with hyper- or hypoglycemia. Further investigation of these potential candidates is needed to enhance clinical utility of these findings.

Conclusion

This study uniquely identifies medications involved in gastrointestinal transit to be predictors of BG that may not well established and recognized in clinical practice.

Etiology of the Neonatal Hypoglycemias

To provide a more appropriate foundation for dealing with the problem of hypoglycemia in newborn infants, this article focuses on the mechanisms which underlie the various forms of neonatal hypoglycemia and discusses their implications for newborn care. Evidence indicates that all of the major forms of neonatal hypoglycemia are the result of hyperinsulinism due to dysregulation of pancreatic islet insulin secretion. Based on these observations, the authors propose that routine measurement of B-hydroxybutyrate should be considered an essential part of glucose monitoring in newborn infants.

Pioneering robotic-assisted surgery for insulinoma during pregnancy: The first case report and literature review

Introduction

Insulinoma during pregnancy is a rare condition with vague clinical symptoms, making diagnosis challenging. The standard treatment for insulinoma is surgical tumor removal, preferably using a minimally invasive method. However, there have been no recorded examples of employing a robotic platform in pregnant women with insulinoma. In this report, we present the first successful case of robotic enucleation for insulinoma during pregnancy.

Case presentation

A 30-year-old pregnant woman presented with recurrent hypoglycemic symptoms throughout her first trimester that were relieved by food intake. After confirming endogenous hyperinsulinemia, an abdominal magnetic resonance imaging scan was performed to locate the tumor. A well-defined 2-cm mass was found in the pancreatic body. Robotic enucleation was performed at week 18 of gestation, and the patient experienced relief from hypoglycemic episodes postoperatively. Her blood glucose levels returned to normal, and she had an uneventful pregnancy. The patient eventually delivered a healthy baby via cesarean section without any complications.

Conclusions

For a subset of pregnant individuals with insulinoma, a minimally invasive approach as robotic-assisted surgery is safe and feasible. This innovative technique has the potential to both mothers and fetuses.

Neoadjuvant Imatinib Therapy for Gastrointestinal Stromal Tumors Associated With Non-islet Cell Tumor Hypoglycemia (NICTH): A Case Report

Non-islet cell tumor hypoglycemia (NICTH) is a rare paraneoplastic syndrome characterized by insulin-like growth factor-2 (IGF-2) release, often associated with diverse tumor types. Gastrointestinal stromal tumors (GISTs), sarcomatous lesions of the gastrointestinal tract, are rarely associated with NICTH. We present a unique case of a 58-year-old patient diagnosed with a GIST exhibiting recurrent hypoglycemia suggestive of NICTH. Despite normal IGF-2 levels, the IGF-2/IGF-1 ratio supported the NICTH diagnosis, which was confirmed histologically. Imaging revealed a large intraperitoneal mass. Hypoglycemia was managed with high-dose dextrose and hydrocortisone. Treatment with the tyrosine kinase inhibitor, imatinib, was initiated. Surprisingly, imatinib not only reduced the tumor size but also improved hypoglycemia. The study highlights the complexities in managing NICTH and its underlying causes. Current diagnostic limitations, treatment modalities, and unexpected therapeutic responses challenge standard approaches. This emphasizes the need for personalized oncological strategies.

Artifactual hypoglycaemia may be common in patients with soft tissue sarcoma who received pegfilgrastim-supported chemotherapy

BACKGROUND

Recently, we identified artifactual hypoglycemia in patients with soft tissue sarcoma (STS) who received pegfilgrastim-supported chemotherapy. In the present study, we measured white blood cell count and fasting blood glucose levels after the administration of pegfilgrastim in patients with STS and showed the relationship between artifactual hypoglycemia and white blood cell count.

PATIENTS

A total of 19 patients were included in this study. The mean age of the patients was 54 years. They received chemotherapy and administration of pegfilgrastim. Pegfilgrastim was injected subcutaneously 48 h after chemotherapy. No patient had a history of diabetes mellitus.

RESULTS

Fifty-nine cycles were administered to 19 patients. One hundred and twenty-eight samples were obtained within one week after the of pegfilgrastim administration. Hypoglycemia was observed in 38 of the 13 patients. There were no symptoms of hypoglycemia in any patient. The white blood cell count in samples from patients with hypoglycemia was significantly higher than that in samples without hypoglycemia (p < 0.001). The median white blood cell count in samples with hypoglycemia was 29,415 and 3420 in samples without hypoglycemia. Age, sex, body mass index, performance status, and red blood cell count were not associated with hypoglycemia. White blood cell count was strongly negatively correlated with fasting blood glucose levels (Pearson's r: 0.786, 95% confidence interval: 0.844-0.709, p < 0.001). Of the 38 samples with hypoglycemia, 32 were measured within 2 days after pegfilgrastim administration.

CONCLUSION

If a lack of symptoms due to hypoglycemia and leukocytes is confirmed, physicians should wait and identify the normalization of the level of glucose according to the neutrophil nadir following temporal leukocytes, which prevents further invasive examination for hypoglycemia.

Short fasting test as a reliable and effective tool to diagnose insulinoma

PURPOSE

The diagnosis of insulinoma can be challenging, requiring documentation of hypoglycaemia associated with non-suppressed insulin and C-peptide, often achieved during a prolonged 72 h fast performed in inpatient setting. Our goal is to predict weather a shorter outpatient fasting test initiated overnight and prolonged up until 24 h could be a sensitive method for diagnosing insulinoma.

METHODS

We conducted a retrospective monocentric study on subjects admitted to our Unit of Endocrinology from 2019 to 2022 for clinical suspicion of insulinoma and underwent the short fasting test. A comparison between the short test group and the group of subjects who underwent the standard prolonged fasting test (from 2003 to 2018) has also been performed. The short fasting test was initiated by the patient overnight at home and proceeded the following day in outpatient setting (Day Hospital). As in the standard protocol, symptoms and capillary blood glucose (CBG) were strictly monitored. Venous blood was drawn for glycaemia, insulin and C-peptide at admission and at established intervals, in case of symptoms of hypoglycaemia or if CBG ≤ 45 mg/dl, when the fast would be suspended.

RESULTS

The final sample consisted of 37 patients, with mean age of 44.5 ± 12.6 years (17-74). Short and standard tests were performed in 15 and 22 subjects, respectively. Diagnostic values for insulinoma were observed in 12 patients: in 5/15 who underwent the short fasting test, in 6/22 who underwent the prolonged test and in 1 patient who was initially negative on the short test and subsequently showed diagnostic values during the prolonged test. The diagnosis of insulinoma was achieved in 11/12 cases within 24 h of the beginning of the fast (91.7%).

CONCLUSIONS

A short fasting test could be a valid, sensitive and reliable first-line workup in diagnosing insulinoma.

Hypoglycemia in non-diabetic in-patients at a teaching referral hospital in Iran

Purpose

This study aims to investigate comorbidities, clinical features, laboratory values, and diagnoses in non-diabetic patients experiencing hypoglycemic episodes.

Methods

A retrospective observational study was conducted at Shariati Hospital in Iran from 2016 to 2023. Seventy-four non-diabetic patients admitted with a diagnosis of hypoglycemia were included, while patients with diabetes were excluded. Demographic data, symptoms, and biochemical assessments were obtained from the hospital information system. Hypoglycemic episodes were identified based on low measured blood glucose, recorded medications for hypoglycemia treatment, or recorded codes indicating hypoglycemia. Hypoglycemia was defined as blood glucose below 70 mg/dL (3.9 mmol/L) along with two other criteria of the Whipple triad. Statistical analysis was performed using SPSS software (version 26).

Results

Among the enrolled patients, 63.5% were female, and 13.5% were elderly (≥ 65 years). The most common comorbidities observed were cardiovascular disease (20.3%), psychological disorders (20.3%), hypothyroidism (14.9%), and hypertension (8.1%). The prevalent symptoms included weakness, loss of consciousness, sweating, palpitations, dizziness, and tremors. Non-diabetic hypoglycemia was caused by factitious disorders, insulinoma, organ failure, and infection, respectively.

Conclusion

Due to the diverse range of clinical symptoms, hypoglycemia in non-diabetic patients may be diagnosed late, leading to misdiagnoses such as psychological disorders or seizures. It is crucial to consider the possibility of hypoglycemia in non-diabetic patients and determine its underlying cause. Given the poor prognosis associated with hypoglycemia, timely interventions are essential.

Idiopathic ketotic hypoglycemia in children: an update

Idiopathic ketotic hypoglycemia (IKH) is defined as bouts of hypoglycemia with increased blood or urine ketones in certain children after prolonged fasting or during illness. IKH is divided into physiological IKH, which is most frequently observed in normal children with intercurrent acute illness, and pathological IKH, which occurs in children who lack counter-regulatory hormones, have a metabolic disease, or have Silver-Russell syndrome. The typical patient is a young child between the ages of 10 months and 6 years. Episodes nearly always occur in the morning after overnight fasting. Symptoms include those of neuroglycopenia, ketosis, or both. IKH may be diagnosed after ruling out various metabolic and hormonal conditions associated with ketotic hypoglycemia. Sufficient amounts of carbohydrates and protein, avoidance of prolonged fasting, and increased frequency of food ingestion are the main modes of treating IKH. It is crucial to understand the pathogenesis of IKH and to distinguish physiological IKH from pathological IKH. In this mini-review, we present a brief summary of IKH in terms of its definition, types, clinical presentation, diagnosis, and therapeutic approach in children.

Recurrent Hypoglycemia in a Non-diabetic Female: A Case Study on Doege-Potter Syndrome

Solitary fibrous tumors (SFT) are mesenchymal cell tumors that may arise from any site throughout the body. A small percentage of patients with SFT develop non-islet cell tumor-induced hypoglycemia (NICTH), eponymously termed Doege-Potter Syndrome (DPS). DPS is characterized by severe, refractory hypoinsulinemic hypoglycemia. Diagnosis of SFT is dependent on histologic findings and immunohistochemistry (IHC). NAB2-STAT6 gene fusions are pathognomonic for SFT but may be difficult to identify in routine cytogenetic studies. STAT6 IHC is a highly sensitive and specific surrogate for the NAB2-STAT6 gene fusion. Total resection of the tumor remains the gold-standard definitive treatment of SFT of the pleura. Palliative tumor debulking is recommended if total resection is not feasible. We here report a case of DPS in a 73-year-old female, managed with palliative care.

An extremely rare case of hypoglycemia with a novel mutation and review of the literature: fructose-1,6 bisphosphatase deficiency in an adult man

Hypoglycemia is an uncommon clinical problem among non-diabetic patients. It requires systematic evaluation to determine the etiology. It may be related to critical illness, hepatic insufficiency, renal insufficiency, cardiac insufficiency, drugs, alcohol, cortisol insufficiency, growth hormone insufficiency, insulinoma, gastric bypass surgery, and paraneoplastic (insulin-like growth factor-2-related) immune-mediated or inherited metabolic disorders. We aimed to summarize the literature and present a case who suffered from hypoglycemia throughout his life and was diagnosed with fructose-1, 6 bisphosphatase deficiency in adulthood to attract attention to the rare causes of hypoglycemia in adulthood.

Insulinoma with Hyperprocalcitoninemia and Hypercalcitoninemia Showing Coexpression of Insulin and Calcitonin in Its Tumor Cells

Neuroendocrine neoplasms can produce multiple hormones that are released into the bloodstream, causing symptoms that vary depending on the type and quantity of hormones involved. We herein report a 63-year-old asymptomatic patient with pancreatic insulinoma who showed marked elevations in circulating calcitonin and procalcitonin levels that returned to normal following surgery. Immunohistochemical analyses confirmed the co-staining of calcitonin and insulin immunoreactivity in the tumor cells, suggesting a calcitonin-producing insulinoma. This insulinoma released calcitonin and a considerable amount of its precursor peptide, procalcitonin, resulting in both hyperprocalcitoninemia and hypercalcitoninemia.

Spontaneous Hypoglycaemia due to Insulin Autoimmune Syndrome in Six Cases, Response to Steroid Therapy and Rituximab

Introduction

Dr. Hirata of Japan first described insulin autoimmune syndrome (IAS) in 1970. Seven hundred ninety-five cases of this rare syndrome have been reported from Japan and China and 29 from India. IAS has the following characteristic features 1) severe spontaneous attacks of hyperinsulinemic hypoglycaemia, 2) high total immunoreactive insulin levels, 3) elevated insulin autoantibody (IAA) titres, 4) no prior exposure to exogenous insulin, and 5) no pathological abnormalities of the pancreatic islet cells.

Methods

We treated six cases of IAS with high doses of prednisolone for 4-6 weeks and then gradually reduced the doses. Diagnosis of IAS was established by documenting Whipple's triad of symptoms and signs of hypoglycaemia, blood sugar <55 mg/dl, improvement of symptoms with dextrose infusion, inappropriately increased insulin levels >3 uU/ml, C-peptide levels >0.6 ng/ml, and increased titres of anti-insulin autoantibodies. Insulinoma and non-pancreatic tumours were ruled out by CECT (contrast-enhanced computerised tomography) or MRI (magnetic resonance imaging) of the abdomen and if necessary endoscopic ultrasonography and gallium 68 Dotanoc PET (positron enhanced tomography). Autoimmune screening and serum electrophoresis were done to rule out multiple myeloma. Monitoring of the patient's blood sugars was done by the laboratory, glucometer readings, and a freestyle libre glucose monitoring system.

Results

Remission of hypoglycaemic episodes, hyperglycaemic episodes, and marked reduction of serum insulin and insulin autoantibodies in four out of six patients with diet therapy and steroids. Two patients resistant to steroids were treated with rituximab successfully. Patient 6 developed serious complications of cytomegalovirus and Pneumocystis carnii after rituximab, which were treated successfully.

Conclusion

A careful history including recent infections, medications, and vaccinations provides vital clues in the evaluation. An increased awareness of IAS will prevent unnecessary and costly investigations and surgery. Although it is often self-remitting, steroids are contributory in severe cases. Immunosuppressives are used successfully in cases refractory to steroids. Continuous glucose monitoring system (CGMS), by freestyle libre glucose monitoring system, provided real-time blood sugar values, total time in hypoglycaemia, and total time in the range (TIR), which proved very valuable in managing IAS patients. Low CGMS values should be corroborated clinically and with laboratory or glucometer values.

Diagnostic Modalities, Management Considerations, and Outcomes of Insulinoma: A Case Series from a Tertiary Care Centre

Introduction

Insulinomas are rare, usually sporadic, and typically benign pancreatic neuroendocrine tumours. Pre-operative localization is challenging and evidence on comparative analysis of anatomic and scintigraphic modalities for pre-operative tumour localization is limited, even in contemporary series.

Methods

The current study was designed to study the clinical features and management challenges of insulinomas managed at a tertiary care centre. Clinical features, diagnosis, imaging techniques, surgical procedures, and outcomes details were collated. Pre-operative imaging techniques (CT/MRI, nuclear scintigraphy) were compared with intraoperative and histopathological findings to assess their accuracy of localization.

Results

Thirty-seven patients (15 females [42%]; median age 36 years [IQR 28-49]) were included in the study. In four patients (10.8%), the tumour occurred in the setting of multiple endocrine neoplasia type 1 (MEN 1) while the remaining were sporadic. The sensitivity of pre-operative localization was 61.5% (multiphasic CT), 66.6% (multiphasic MRI), 100% (68Ga Exendin-4 PET-CT), and 91.6% (EUS). Three patients with normal multiphasic CT had localization on 68Ga Exendin-4 PET-CT. The positive predictive value (PPV) of both Exendin-PET-CT and EUS was similar at 91.6% and 91.6%, respectively. All patients (except one with nesidioblastosis), who underwent enucleation or partial pancreatic resection, were cured.

Conclusion

68Ga Exendin-4 PET-CT based is a non-invasive imaging modality that has high sensitivity and PPV and can be used as a first-line imaging modality. The overall prognosis of these tumours is good with high cure rates attained following surgical resection.

A Rare Case of Insulin-Like Growth Factor (IGF-2) Induced Hypoglycemia Associated With Metastatic Colon Cancer

The occurrence of hypoglycemia in patients without diabetes is rare, and non-islet cell tumor hypoglycemia (NICTH) accounts for a small portion of these instances. One of the infrequent causes is associated with tumor cell production of Insulin-like growth factor (IGF)-2. Here is a case of a 66-year-old man with stage IV colon cancer who presented to the emergency department with breathlessness during chemotherapy (Bevacizumab plus FOLFOX4 regimen). He had undergone partial colectomy and chemotherapy three years prior but was recently diagnosed with metastatic liver disease. A CT scan revealed a 15 cm hepatic mass occupying the entire right hepatic lobe. Despite receiving dextrose infusions, he experienced persistent hypoglycemia after meals and during fasting. Given that he had no history of diabetes and denied using any oral hypoglycemic agents, the Endocrinology service was consulted for further evaluation. Plasma blood glucose (BG) was measured at 74 mg/dL (reference range 74-106) during dextrose administration. An 8 AM cortisol test yielded a result of 8.08 mcg/dL (4.30-22.40), ruling out adrenal insufficiency. A 72-hour fast was initiated but terminated at eight hours due to symptomatic hypoglycemia with a plasma BG of 48 mg/dL. C-peptide and Insulin levels were both low, measuring <0.05 ng/mL (0.48-5.05) and <1.0 mU/L (3.0-25), respectively, while beta-hydroxybutyrate (BHB) levels were normal at 1.1 mg/dL (0.2-2.8). Administration of 1 mg glucagon during the fast increased BG to 112 mg/dL within 2 hours. IGF-1 levels were undetectable (<1.9 nmol/L), while IGF-2 levels were at 23 nmol/L (44-129 nmol/L), resulting in an IGF2:IGF1 ratio of 12 (>10), confirming IGF-2 mediated NICTH. Treatment with dexamethasone 10 mg daily was initiated, maintaining blood glucose levels above 70 mg/dL without dextrose infusion. In approximately 50% of cases of NICTH, the tumor is detected before the onset of hypoglycemia, yet up to half the patients may remain asymptomatic despite having very low BG. Despite having a known hepatic lesion, our patient exhibited minimal symptoms despite severely low BG levels. The mechanisms underlying NICTH may involve tumor secretion of insulin, replacement of hepatic tissue, increased glucose utilization by the tumor, or, most commonly, secretion of IGF-2. In cases of IGF-2-mediated hypoglycemia, insulin, proinsulin, C-peptide, and β-hydroxybutyrate levels are typically low. IGF-2 stimulates the insulin receptors resulting in increased glucose uptake by skeletal muscles and suppression of gluconeogenesis, glycogenolysis, and ketogenesis by the liver. Insulin secretion from pancreatic β-cells is suppressed. IGF-1 levels are usually low, while IGF-2 levels may be high or normal, as many IGF-2omas produce IGF-2 precursors (pro-IGF-2). An elevated IGF-2:IGF-1 ratio (>10) confirms the diagnosis which may be helpful when IGF-2 levels are normal. The primary treatment is through surgical removal or debulking of the tumor. Neoadjuvant therapies such as radiation and chemotherapy may reduce occurrences of hypoglycemia, but only temporarily. Glucocorticoids may be used when the underlying malignancy cannot be treated.

Insulinoma Unmasked Post Sleeve Gastrectomy With Incidental Renal Cell Carcinoma: A Rare Case

Insulinoma is a functional pancreatic neuroendocrine tumor (pNET). Usually benign and solitary, these tumors present with recurrent episodes of hypoglycemia due to insulin hypersecretion. It's a rare cause of post bariatric surgery hypoglycemia and hence poses a diagnostic challenge. Here, we report the first case of a 53-year-old male with insulinoma unmasked post sleeve gastrectomy with incidental renal cell carcinoma (RCC). He presented with symptoms of Whipple's triad after two months of sleeve gastrectomy done for morbid obesity. On further inquiry, the patient gave a history of an asymptomatic peripancreatic neuroendocrine tumor (NET) for the past 11 years. With a suspicion of insulinoma, biochemical workup followed by non-invasive imaging like GA-68 DOTA and CT triphasic abdomen scan was done to guide the diagnosis of an insulinoma which also detected a second primary tumor in the right kidney, likely to be a malignant RCC. Following pancreatic mass excision with radical nephrectomy for right renal mass, histopathology (HPE) and immunohistochemistry (IHC) confirmed the diagnosis of an insulinoma and a right renal clear cell carcinoma. The patient was discharged with no further episodes of hypoglycemia. Hence, persistent hypoglycemia post bariatric surgery could be an indication of a hidden insulinoma and this possibility of synchronous tumors should be kept in mind when dealing with rare tumors like insulinoma.

How should we differentiate hypoglycaemia in non-diabetic patients?

Hypoglycaemic syndromes are rare in apparently healthy individuals and their diagnosis can be a difficult challenge for clinicians as there are no shared guidelines that suggest how to approach patients with a suspect hypoglycaemic disorder. Since hypoglycaemia symptoms are common and nonspecific, it's necessary to document the Whipple Triad (signs and/or symptoms compatible with hypoglycaemia; relief of symptoms following glucose administration; low plasma glucose levels) before starting any procedure. Once the triad is documented, a meticulous anamnesis and laboratory tests (blood glucose, insulin, proinsulin, C-peptide, β-hydroxybutyrate and anti-insulin antibodies) should be performed. Results can guide the physician towards further specific tests, concerning the suspected disease. In this review, we consider all current causes of hypoglycaemia, including rare diseases such as nesidioblastosis and Hirata's syndrome, describe appropriate tests for diagnosis and suggest strategies to differentiate hypoglycaemia aetiology.

Impact of Glucocorticoid Replacement Therapy on Nocturnal Hypoglycemia in Adrenal Insufficiency: An Analysis of Multiple Case Studies

BACKGROUND AND AIM

Adrenal insufficiency (AI) is a hormonal disorder characterized by insufficient glucocorticoid production. Nocturnal hypoglycemia (NH) occurs in patients with AI. However, the effect of glucocorticoid replacement therapy (GCRT) on AI and NH remains unclear. This study aimed to investigate the relationship between AI and NH by evaluating the impact of GCRT on NH in patients newly diagnosed with AI.

METHODS

The present study was conducted between October 2018 and December 2022 at the Department of Diabetes, Metabolism and Endocrinology of the Tokyo Rosai Hospital, Japan. In total, 15 patients aged ≥18 years with newly diagnosed AI or NH were included in this study. The NH frequency was measured using continuous glucose monitoring (CGM). The primary outcome was the change in NH frequency before and after the GCRT intervention.

RESULTS

GCRT significantly decreased NH frequency. Severe NH frequency and minimum nocturnal glucose levels changed significantly while fasting blood glucose and glycated hemoglobin levels did not change significantly. GCRT intervention improved CGM profiles' time below range, time in range, and average daily risk range.

CONCLUSIONS

 The present study suggests that GCRT can help newly diagnosed patients with AI manage NH. These findings show that CGM can detect NH in patients with newly diagnosed AI, determine the optimal GCRT dosage, and hence prevent an impaired quality of life and even serious adverse effects in these patients. Further large multicenter studies should validate these findings and delve deeper into the mechanistic link between AI and NH.

Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors

The incidence of pancreatic neuroendocrine tumors (PNETs) is on the rise primarily due to the increasing use of cross-sectional imaging. Most of these incidentally detected lesions are non-functional PNETs with a small proportion of lesions being hormone-secreting, functional neoplasms. With recent advances in surgical approaches and systemic therapies, the management of PNETs have undergone a paradigm shift towards a more individualized approach. In this manuscript, we review the histologic classification and diagnostic approaches to both functional and non-functional PNETs. Additionally, we detail multidisciplinary approaches and surgical considerations tailored to the tumor's biology, location, and functionality based on recent evidence. We also discuss the complexities of metastatic disease, exploring liver-directed therapies and the evolving landscape of minimally invasive surgical techniques.

Schmidt's Syndrome: An Uncommon Cause of Spontaneous Hypoglycemia

Schmidt's syndrome, or autoimmune polyendocrine syndrome type 2 (APS-2), is an uncommon disorder characterized by the co-occurrence of autoimmune thyroiditis and adrenalitis. APS-2 is defined as a combination of Addison's disease, autoimmune thyroid disease, and/or type 1 diabetes mellitus. It is an autosomal dominantly inherited polygenic disorder with incomplete penetrance; the candidate genes include but are not limited to HLA-DR3, HLA-DR4, CTLA-4, PTPN22, and CD25-IL-2. Autoimmune thyroiditis, often Hashimoto's disease, results in hypothyroidism. Primary adrenal failure results in enhanced secretion of adrenocorticotrophic hormone melanocyte and co-secretion of melanocyte-stimulating hormone, contributing to hyperpigmentation. Mineralocorticoid deficiency results in salt wasting, fatigue and cramps, postural hypotension, and hyperkalemia. Cortisol, an insulin counter-regulatory hormone, plays a pivotal role in maintaining euglycemia; deficiency predisposes to the development of hypoglycemia. We here report a rare presentation of Schmidt's syndrome as hypoinsulinemic hypoglycemia in a middle-aged male patient. Management includes treatment of acute hypoglycemic episodes with glucose or glucagon, long-term glucocorticoids and mineralocorticoids for adrenal insufficiency, and thyroid hormone supplements for hypothyroidism. This case report and brief overview aim to contribute to the scientific understanding of Schmidt's syndrome/APS-2. Additionally, here we briefly outline the diagnostic challenges in hypoglycemia evaluation, including the utilization of Whipple's triad and the gold standard supervised 72-hour fast and evaluation for primary adrenal and thyroid insufficiencies.

Persistent Insulin Autoimmune Syndrome in a Caucasian Male in the Absence of Triggers

Insulin autoimmune syndrome (IAS) or Hirata disease is a rare condition presenting as recurrent hypoglycemia, and associated with elevated insulin levels in the presence of insulin autoantibodies (IAAs) in patients who were never exposed to exogenous insulin and with no evidence of pancreatic abnormalities. IAS is much more frequent in East Asians, especially the Japanese population, compared to the lower incidence in Caucasians. However, it can be associated with other autoimmune diseases or drug use like methimazole and alpha-lipoic acid (ALA). We report a case of a 47-year-old Caucasian male presenting with a 12-month history of worsening episodes of fasting and post-prandial hypoglycemia associated with symptoms of dizziness, tremors, palpitations, and unconsciousness associated with hypoglycemia. Symptoms resolved with the administration of carbohydrate-containing foods, establishing Whipple's triad. At an outside facility, he had initial labs that showed elevated insulin levels (141 µU/ml) with normal glucose, C-peptide, and proinsulin levels, but there was no availability of an IAA lab assay. Given his symptoms, severity, and frequency of hypoglycemia, he was admitted to the hospital for a 72-hour fast, which showed the lowest glucose level of 64 mg/dl with inappropriately high insulin of 22.2 µU/ml, low C-peptide of 0.57 ng/ml, and undetectable proinsulin of <1.6 pmol/L, but with IAA being >50 U/ml (0.0-0.4 U/ml). He was treated with intensive dietary counseling with a low-carbohydrate diet and prednisone 20 mg twice daily initially. Additionally, he could not tolerate octreotide, diazoxide, and acarbose due to side effects. He is currently on prednisone 10 mg daily and nifedipine with no further hypoglycemic episodes, but still has a high IAA of >50 U/ml and serum insulin levels of 70-112 µU/ml. Our case highlights the importance of recognizing hypoglycemia and checking for IAA levels as first-line diagnostic tests, in the absence of which there could be a delay in diagnosis and leading to unnecessary lab and imaging testing. Our case is unique since it happened in a Caucasian without any prior exposure to a triggering factor and has not undergone self-remission yet, which happens in most of IAS cases.

A Case of Acromegaly With Progressed Diabetic Retinopathy and Sarcopenia Diagnosed Following the Onset of Severe Hypoglycemia

Acromegaly is a rare disorder characterized by excessive production of growth hormone (GH) from a pituitary tumor, typically leading to elevated glucose levels due to increased insulin resistance; hypoglycemia is rare. However, the long-term effect of excess GH on the peripheral organs is still unclear. Here we present a 69-year-old man evaluated for the cause of a hypoglycemic episode. He was underweight (body mass index: 17.3 kg/m2) with sarcopenia, which potentially contributed to his hypoglycemia. Notably, he exhibited progressed proliferative diabetic retinopathy compared to other microvascular complications, leading to further endocrinological investigation. As a result, he was diagnosed with acromegaly showing elevated GH and insulin-like growth factor-1 (IGF-1) with a pituitary tumor. Opting against transsphenoidal surgery (TSS), the patient was treated with a somatostatin analog (SSA), achieving normalized IGF-1 levels with a monthly 120 mg lanreotide injection. In this case, acromegaly could lead to sarcopenia from GH-derived gluconeogenesis in the peripheral organs such as the reduction of muscle leading to reduced glucose reserves. Acromegaly in the elderly may present atypicality. Clinicians should be vigilant for unique manifestations such as advanced diabetic retinopathy, even in elderly patients with hypoglycemia.

Approach to the Patient: Insulinoma

Insulinomas are hormone-producing pancreatic neuroendocrine neoplasms with an estimated incidence of 1 to 4 cases per million per year. Extrapancreatic insulinomas are extremely rare. Most insulinomas present with the Whipple triad: (1) symptoms, signs, or both consistent with hypoglycemia; (2) a low plasma glucose measured at the time of the symptoms and signs; and (3) relief of symptoms and signs when the glucose is raised to normal. Nonmetastatic insulinomas are nowadays referred to as "indolent" and metastatic insulinomas as "aggressive." The 5-year survival of patients with an indolent insulinoma has been reported to be 94% to 100%; for patients with an aggressive insulinoma, this amounts to 24% to 67%. Five percent to 10% of insulinomas are associated with the multiple endocrine neoplasia type 1 syndrome. Localization of the insulinoma and exclusion or confirmation of metastatic disease by computed tomography is followed by endoscopic ultrasound or magnetic resonance imaging for indolent, localized insulinomas. Glucagon-like peptide 1 receptor positron emission tomography/computed tomography or positron emission tomography/magnetic resonance imaging is a highly sensitive localization technique for seemingly occult, indolent, localized insulinomas. Supportive measures and somatostatin receptor ligands can be used for to control hypoglycemia. For single solitary insulinomas, curative surgical excision remains the treatment of choice. In aggressive malignant cases, debulking procedures, somatostatin receptor ligands, peptide receptor radionuclide therapy, everolimus, sunitinib, and cytotoxic chemotherapy can be valuable options.

From liver to hormones: The endocrine consequences of cirrhosis

Hepatocrinology explores the intricate relationship between liver function and the endocrine system. Chronic liver diseases such as liver cirrhosis can cause endocrine disorders due to toxin accumulation and protein synthesis disruption. Despite its importance, assessing endocrine issues in cirrhotic patients is frequently neglected. This article provides a comprehensive review of the epidemiology, pathophysiology, diagnosis, and treatment of endocrine disturbances in liver cirrhosis. The review was conducted using the PubMed/Medline, EMBASE, and Scielo databases, encompassing 172 articles. Liver cirrhosis is associated with endocrine disturbances, including diabetes, hypoglycemia, sarcopenia, thyroid dysfunction, hypogonadotropic hypogonadism, bone disease, adrenal insufficiency, growth hormone dysfunction, and secondary hyperaldosteronism. The optimal tools for diagnosing diabetes and detecting hypoglycemia are the oral glucose tolerance test and continuous glucose monitoring system, respectively. Sarcopenia can be assessed through imaging and functional tests, while other endocrine disorders are evaluated using hormonal assays and imaging studies. Treatment options include metformin, glucagon-like peptide-1 analogs, sodium-glucose co-transporter-2 inhibitors, and insulin, which are effective and safe for diabetes control. Established standards are followed for managing hypoglycemia, and hormone replacement therapy is often necessary for other endocrine dysfunctions. Liver transplantation can address some of these problems.

Role of beta-hydroxybutyrate measurement in the evaluation of plasma glucose concentrations in newborn infants

OBJECTIVE

The Glucose in Well Babies (GLOW) Study showed that there are two phases of low glucose concentrations in healthy newborn infants: an initial phase in which plasma concentrations of ketones are low; and a second phase in which low glucose concentrations are accompanied by elevated concentrations of ketones. The implications of these two phases for the brain differ depending on whether ketones are available as alternative substrate for brain metabolism. The purpose of this study was to estimate the duration of these two phases of neonatal low glucose concentrations in 66 healthy breastfed newborns from the GLOW Study during the first 5 days of life.

METHODS

The sum of glucose and beta-hydroxybutyrate (BOHB) was used as a proxy for the total concentrations of insulin-dependent fuels for the brain; a threshold value below 4 mmol/L was taken to indicate the presence of relative hyperinsulinism and a BOHB concentration above 0.5 mmol/L to indicate ketonaemia.

RESULTS

The first phase of low glucose concentrations lasted a median of 40 hours and in 15% of infants, this persisted beyond 60 hours. Fifty (76%) of the 66 infants subsequently had ketonaemia, which resolved at a median age of 76 hours (range 41->120 hours).

CONCLUSIONS

These data suggest that monitoring BOHB concentrations may be useful for interpreting glucose concentrations in newborns and screening for persistent hyperinsulinism.

An Unusual Case of Hypoglycemia in a Non-diabetic Individual due to Hirata Disease

Hypoglycemia is common in diabetic populations using insulin or insulin secretagogues, but rare in non-diabetics. A 60-year-old non-diabetic male presented with repeated episodes of abnormal behavior persisting for 10-15 minutes for seven days, associated with sweating, intense hunger, and relief on food intake, with no history of insulin or secretagogue intake, with stable vitals and normal systemic examination. Laboratory tests during attacks revealed low blood sugar, high serum insulin, and normal C-peptide levels, with no evidence of pancreatic or extrapancreatic hyperinsulinism, and serum anti-insulin antibody levels >100 U/ml. Based on these results, he was diagnosed with autoimmune insulin syndrome (AIS). Treatment with low-carb meals, oral prednisolone, and acarbose led to the resolution of symptoms. Hirata syndrome, though rare in India, requires consideration as a differential diagnosis to avoid unnecessary invasive procedures.

The safety of preoperative carbohydrate drinks in extremely elderly patients assessed by gastric ultrasonography: a randomized controlled trial

BACKGROUND

Modern perioperative guidelines encourage drinking oral carbohydrates 2 h before management. Nevertheless, research on the safety of preoperative carbohydrate drinks, particularly in extremely elderly patients is lacking. We aimed to evaluate the safety of carbohydrate drinks 2 h before surgery in extremely elderly patients (≥ 80 years) using gastric ultrasonography.

METHODS

We conducted a randomized prospective comparative study of 70 patients aged over 80 years who were scheduled for total knee arthroplasty, hip fracture or humerus fracture surgery. These patients were randomly assigned to the carbohydrate group (n = 35), which fasted from midnight, except for drinking 355 mL of a carbohydrate-containing fluid 2 h before surgery, or the fasting group (n = 35), which fasted from midnight and drank no fluid before surgery. The primary outcome of the study was the cross-sectional area (CSA) of the gastric antrum in the right lateral decubitus position (RLDP) before surgery. The secondary outcomes included CSA in the supine position, intraoperative blood glucose levels and their variability coefficients, Perlas grade, and the visual analog scale of subjective feelings.

RESULTS

The CSA in the RLDP and supine positions revealed no differences between the carbohydrate and fasting groups at 0 h preoperatively (P > 0.05). In the qualitative assessment, preoperative 0-h Perlas grading did not differ significantly between the groups (P > 0.05). From 2 h before surgery to transfer out of the post-anesthesia care unit, the average blood glucose level of patients in the carbohydrate group was significantly higher than that in the fasting group (P < 0.001) but remained within the normal range. Moreover, the blood glucose variability coefficient was significantly lower in the carbohydrate group than in the fasting group (P = 0.009). Oral intake of 355 mL carbohydrates before surgery significantly relieved patients' feelings (P < 0.001).

CONCLUSION

Preoperative consumption of carbohydrate drinks 2 h before surgery is safe in "healthy" extremely elderly patients. In addition, preoperative drinking has potential value in maintaining ideal blood glucose levels and stable blood glucose fluctuations perioperatively and improving subjective perceptions of preoperative preparation. This finding warrants further investigation in clinical practice.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (Registration Number ChiCTR1900024812), first registered on 29/07/2019.

Homeostasis Model Assessment of β-Cell Function for Diagnosis of Insulinoma

CONTEXT

Diagnosis of insulinoma is based on different criteria from the 72-hour fasting test according to current guidelines (Endocrine Society [ES], European [ENETS], and North American [NANETS] Neuroendocrine Tumor Societies), including assessment of β-cell function by glucagon stimulation test.

OBJECTIVE

This study tested whether the homeostasis model assessment of insulin secretion, including assessment of β-cell function, (HOMA-B) at the end of the fasting test provides comparable efficacy for insulinoma diagnosis.

METHODS

In 104 patients with suspected insulinoma, 72-hour fasting tests were performed with frequent assessment of glucose, insulin, and C-peptide in venous blood. HOMA-B values using insulin and C-peptide were calculated at the end of the fasting test, as defined by the lowest glucose concentration from each participant.

RESULTS

HOMA-B was more than 6.5-fold higher in patients with (n = 23) than in those without (n = 81) insulinoma (insulin and C-peptide; both P < .001). HOMA-B (cutoff using insulin >253 a.u. and C-peptide >270 a.u.) had a sensitivity of 0.96, 0.78 to 1.00, and a specificity of 0.96 or greater (≥0.89-0.99) for insulinoma diagnosis. ES and ENETS/NANETS criteria reached a diagnostic sensitivity of less than or equal to 0.96 (≤0.78-1.00) and ≤0.83 (≤0.61-0.95) as well as specificity of ≤0.85 (≤0.76-0.92) and less than or equal to 1.00 (≤0.96-1.00) for insulin, and C-peptide, respectively. Using insulin for HOMA-B, sensitivity tended to be higher compared to ENETS/NANETS criteria (P = .063) and specificity was higher compared to ES criteria using insulin and C-peptide (both P < .005).

CONCLUSION

HOMA-B, as calculated at the end of the fasting test employing defined cutoffs for insulin and C-peptide, provides excellent diagnostic efficacy, suggesting that it might represent an alternative and precise tool to diagnose insulinoma.

De-escalating treatment indications for patients who achieve metabolic goals

INTRODUCTION

Robust evidence exists regarding initiation, intensification or modification of treatments. Recommendations to de-escalate therapy are lacking, specifically in diabetes. A successful treatment de-intensification reduces overtreatment, polypharmacy, and risk of adverse effects.

OBJECTIVE

To encompass current recommendations for deprescribing common drugs and create a consensus among health professionals.

METHODS

We reviewed four databases for deprescribing approaches published between 2010 and 2022. Articles were divided into different groups of drugs (for uric-acid, hypoglycemic, lipid-lowering, and psychotropic drugs).

RESULTS

Hypoglycemic agents: strategies were limited to newer agents and insulin regimens for elderly individuals. Reducing insulin was associated with 1.1% reduction of A1c over time. SGLT2i and GLP-1RAs dose reduction depends on adverse events. Lipid-lowering agents: studies show that patients with very low cholesterol have fewer cardiovascular events without associated increased risk. Antihypertensive agents: Younger patients, lower systolic blood pressure, and few comorbidities are ideal characteristics for discontinuation. Uric acid therapy: we found no recommendation for dose de-escalation. Poor treatment adherence is associated with episodes of gout and deforming arthritis in the long term.

CONCLUSION

Deprescribing hypoglycemic, statins, antihypertensives, and urate-lowering agents may be feasible in selected patients, but periodic surveillance is important. More evidence is necessary to support this decision entirely.

Reactive Hypoglycemia in Patients Prior to Cataract Surgery: A Case Series

Cataract surgery is one of the most frequently performed surgical procedures and is often performed under topical anesthesia in conscious patients. Sweating, palpitations, and anxiety may be seen in patients about to undergo surgery. However, these are typical adrenergic symptoms of hypoglycemia and should be further investigated if occurring before surgery. Here, we report five cases of postprandial or reactive hypoglycemia observed in hospital settings just before conducting cataract surgeries in non-diabetic 52-78-year-old patients from 2019 to 2023.

A Rare Cause of Hypoglycemia in Elderly Patients: Insulinoma

Insulinoma is the most common pancreatic neuroendocrine tumor and is often solitary and benign. To make a diagnosis, high insulin levels must be demonstrated, and proinsulin and C-peptide measurements must be done. The presence of hypoglycemic measurements and symptoms in the 72-hour fasting test is diagnostic. We present a case of a 91-year-old patient with no known diagnosis of diabetes mellitus who was admitted to the emergency department due to confusion. As a result of the clinical evaluation and differential diagnosis, it was determined that her complaint was due to hypoglycemia, and she was admitted to the internal medicine service for further examination, diagnosis, and treatment.

Unraveling the Whipple Triad: Non-Islet Cell Tumor-Induced Hypoglycemia

Tumor-induced hypoglycemia (TIH) is a rare paraneoplastic phenomenon resulting from several tumor types and mechanisms. Insulinomas are the most common cause of TIH. However, non-islet cell tumors can also trigger hypoglycemia by releasing insulin-like growth factor 2 (IGF-II) or its precursor. We present a case of a 56-year-old woman experiencing spontaneous hypoglycemia due to a pleural-based solitary fibrous tumor. Diagnostic evaluations revealed diminished C-peptide levels, increased IGF-II, and a 4-fold increase in the IGF-II: IGF-I ratio, indicative of non-islet cell tumor hypoglycemia. Localization imaging identified a left pleural mass, confirming the diagnosis. Preoperatively, the patient received intravenous dextrose and corticosteroids, but surgical resection was essential for the resolution of symptoms. The identified tumor, a benign solitary fibrous tumor, was successfully removed, leading to an immediate postoperative cessation of hypoglycemia. Six years post resection, the patient remains symptom free. Managing TIH necessitates an early diagnosis aiming for complete tumor resection, with alternative approaches considered when complete resection is not possible. This case highlights the importance of a systematic diagnostic and management approach for TIH, emphasizing the need to identify the underlying cause, particularly in people without diabetes.

Pharmacologic inhibition of somatostatin receptor 2 to restore glucagon counterregulation in diabetes

Glucose homeostasis is primarily maintained by pancreatic hormones, insulin and glucagon, with an emerging role for a third islet hormone, somatostatin, in regulating insulin and glucagon responses. Under healthy conditions, somatostatin secreted from pancreatic islet δ-cells inhibits both insulin and glucagon release through somatostatin receptor- induced cAMP-mediated downregulation and paracrine inhibition of β- and α-cells, respectively. Since glucagon is the body's most important anti-hypoglycemic hormone, and because glucagon counterregulation to hypoglycemia is lost in diabetes, the study of somatostatin biology has led to new investigational medications now in development that may help to restore glucagon counterregulation in type 1 diabetes. This review highlights the normal regulatory role of pancreatic somatostatin signaling in healthy islet function and how the inhibition of somatostatin receptor signaling in pancreatic α-cells may restore normal glucagon counterregulation in diabetes mellitus.

Lower Incidence of Hypoglycemia With Angiotensin Receptor Blocker Versus ACE Inhibitor Therapy in People With or Without Diabetes

This article describes a study examining the association between treatment with ACE inhibitors or angiotensin receptor blockers (ARBs) and incident hypoglycemia in patients with or without diabetes who were admitted to the internal medicine departments of a tertiary hospital in the Tel Aviv district of Israel. The authors found that treatment with ARBs, but not ACE inhibitors, compared with treatment with neither, was associated with a reduced risk of hypoglycemia regardless of diabetes status.

Case report: Insulinomatosis: description of four sporadic cases and review of the literature

The best-known etiologies of hyperinsulinemic hypoglycemia are insulinoma, non-insulinoma pancreatogenous hypoglycemic syndrome, autoimmune processes, and factitious hypoglycemia. In 2009, a disease not associated with classic genetic syndromes and characterized by the presence of multiple pancreatic lesions was described and named insulinomatosis. We present the clinical and pathologic features of four patients with the diagnosis of insulinomatosis, aggregated new clinical data, reviewed extensively the literature, and illustrated the nature and evolution of this recently recognized disease. One of our patients had isolated (without fasting hypoglycemia) postprandial hypoglycemia, an occurrence not previously reported in the literature. Furthermore, we reported the second case presenting malignant disease. All of them had persistent/recurrent hypoglycemia after the first surgery even with pathology confirming the presence of a positive insulin neuroendocrine tumor. In the literature review, 27 sporadic insulinomatosis cases were compiled. All of them had episodes of fasting hypoglycemia except one of our patients. Only two patients had malignant disease, and one of them was from our series. The suspicion of insulinomatosis can be raised before surgery in patients without genetic syndromes, with multiple tumors in the topographic investigation and in those who had persistent or recurrent hypoglycemia after surgical removal of one or more tumors. The definitive diagnosis is established by histology and immunohistochemistry and requires examination of the "macroscopically normal pancreas." Our case series reinforces the marked predominance in women, the high frequency of recurrent hypoglycemia, and consequently, a definitive poor response to the usual surgical treatment.

Progress and application of adipose-derived stem cells in the treatment of diabetes and its complications

Diabetes mellitus (DM) is a serious chronic metabolic disease that can lead to many serious complications, such as cardiovascular disease, retinopathy, neuropathy, and kidney disease. Once diagnosed with diabetes, patients need to take oral hypoglycemic drugs or use insulin to control blood sugar and slow down the progression of the disease. This has a significant impact on the daily life of patients, requiring constant monitoring of the side effects of medication. It also imposes a heavy financial burden on individuals, their families, and even society as a whole. Adipose-derived stem cells (ADSCs) have recently become an emerging therapeutic modality for DM and its complications. ADSCs can improve insulin sensitivity and enhance insulin secretion through various pathways, thereby alleviating diabetes and its complications. Additionally, ADSCs can promote tissue regeneration, inhibit inflammatory reactions, and reduce tissue damage and cell apoptosis. The potential mechanisms of ADSC therapy for DM and its complications are numerous, and its extensive regenerative and differentiation ability, as well as its role in regulating the immune system and metabolic function, make it a powerful tool in the treatment of DM. Although this technology is still in the early stages, many studies have already proven its safety and effectiveness, providing new treatment options for patients with DM or its complications. Although based on current research, ADSCs have achieved some results in animal experiments and clinical trials for the treatment of DM, further clinical trials are still needed before they can be applied in a clinical setting.

Insulinoma Presenting as Seizures: Challenges of Managing a Rare Disease in a Resource-challenged Setting

Insulinomas are functioning pancreatic neuroendocrine tumors (NETs). They secrete insulin, and hence, present with hypoglycemia. We report a case of insulinoma in a 16-year-old girl presenting as seizures. She was initially managed at a private clinic and later commenced on carbamazepine when convulsion persisted. Convulsions were generalized, associated with dizziness and altered sensorium, often preceded by hunger and physical exertion, but relieved by the intake of carbonated drinks and fruit juice. She was referred to the neurology clinic when seizures persisted, despite the use of anticonvulsant. She was later referred to the endocrine clinic on suspicion of insulinoma when her random blood glucose (BG) was found to be low during an episode of convulsion. She was moderately obese but other examination findings were normal. She had a 72-hour prolonged fast, which was terminated when hypoglycemia (BG = 2.2 mmol/L) ensued after 12 hours, with elevated serum insulin and C-peptide. Abdominal magnetic resonance imaging scan showed a pancreatic tumor suggestive of insulinoma. She subsequently had distal pancreatectomy performed with complete resolution of symptoms. Unusual presentation of insulinoma may delay diagnosis, resulting in wastage of resources with increased morbidities and mortality.

Evaluation of plasma cortisol during fasting test in patients with endogenous hyperinsulinemic hypoglycemia. Fifteen years experience

BACKGROUND

Endogenous hyperinsulinemic hypoglycemia (EHH) is a rare clinical condition. The aim of this study was to evaluate baseline plasma cortisol concentration and its concentration during hypoglycemic crisis in fasting tests (FT) performed in our center. Secondarily, the aim was to establish the relationship between baseline cortisol and the time of evolution of EHH.

MATERIAL AND METHODS

A retrospective, observational, descriptive study was carried out which included patients with hypoglycemic disorder with positive FT.

RESULTS

Of a total of 21 patients, 16 presented insulinoma, 1 nesidioblastosis, 2 malignant insulinoma and 2 EHH without pathological diagnosis. The time from the onset of symptoms to diagnosis was 2 years (Q1=1.5-Q2=5.5). The comparison between median baseline cortisol (BC)=11.8 mcg/dl (nmol/L 340.68) (Q1=9-Q3=14.1) and median cortisol during hypoglycemic episode (HC)=11.6 mcg/dl (nmol/L: 303.44) (Q1=7.8-Q3=16.1) showed no differences (Z=-0.08; P>.05). When correlating BC with HC, no significant relationship was observed (r=0.16; P>.05). When correlating the glycemic value in the crisis and the HC, a slight negative trend was found (r=-0.53; P=.01). In addition, we found that recurrent hypoglycemic disorder is associated with lower baseline cortisol values ​​the longer the time of its evolution.

CONCLUSION

We confirmed that cortisol values ​​remain low during hypoglycemic episodes, reinforcing the hypothesis of lack of response of this counterregulatory hormone in cases of recurrent hypoglycemia.

Clopidogrel-induced non-diabetic hypoglycemia reported from Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia: a case report

BACKGROUND

Recurrent episodes of hypoglycemia may be caused by several factors, including drugs, critical illnesses, hormonal deficiency, non-islet cell tumor endogenous hyperinsulinism, and accidental, surreptitious, or malicious hypoglycemia. Multiple drugs have been previously reported as causes of hypoglycemia, with moderate and low-quality evidence. However, Clopidogrel as a cause of non-diabetic hypoglycemia is rarely reported. Here we describe a single non-diabetic patient who experienced recurrent episodes of hypoglycemia after initiation of clopidogrel for clinical suspicion of acute coronary syndrome.

CASE PRESENTATION

The patient, a 33-year-old Ethiopian male with documented hypertension on antihypertensive medication, has started receiving treatment for acute coronary syndrome after experiencing angina symptoms. He experienced hypoglycemia following the start of Clopidogrel, but it subsided once it was stopped. Currently, he has a follow-up at the cardiac clinic with a normal measurement of his serum blood glucose level.

CONCLUSION

Non-diabetic hypoglycemia is a rare illness characterized by low blood glucose levels in people who do not have diabetes. Patients with severe hypoglycemia may become unconscious or have seizures as a result of low blood sugar. Severe hypoglycemia is fatal and must be treated as soon as possible. Therefore, if non-diabetic hypoglycemia occurs, a thorough evaluation of the causes is essential, particularly any potential drug as a cause of hypoglycemia should be evaluated.

Approach to the Hypoglycemic Patient

Hypoglycemia is commonly encountered in the emergency department. Patients can present with a myriad of symptoms and its presentation can mimic other more serious diagnoses. Despite the relative ease of its management, clinicians often miss the diagnosis or mismanage it even when discovered. Glucose is an important energy source for the brain and failing to recognize hypoglycemia or mismanaging it can lead to permanent neurologic disability or death. Although it is important to replenish glucose in a rapid fashion, it is equally important to discover and manage the underlying etiology to prevent further episodes of hypoglycemia.

Investigation and Causes of Spontaneous (Non-Diabetic) Hypoglycaemia in Adults: Pitfalls to Avoid

Although adult spontaneous (non-diabetic) hypoglycaemia is rare, its recognition is important for the preventative or curative treatment of the underlying cause. Establishing Whipple's triad-low blood glucose, neuroglycopaenia and resolution of neuroglycopaenia on increasing blood glucose levels to normal or above-is essential to verify hypoglycaemia. Awareness that hypoglycaemia may occur in severely ill patients is important for its prevention. Further investigation in such cases is unnecessary unless another cause of hypoglycaemia is suspected. Patients are often asymptomatic and normoglycaemic at review. Their history of medication, self-medication, access to hypoglycaemic drugs, alcohol use and comorbidity may provide aetiological clues. The investigation involves obtaining blood samples during symptoms for laboratory glucose measurement or provoking fasting or postprandial hypoglycaemia as directed by symptoms. If confirmed, insulin, c-peptide, proinsulin and beta-hydroxybutyrate are analysed in hypoglycaemic samples. These will classify hypoglycaemia due to non-ketotic hyperinsulinaemia, non-ketotic hypoinsulinaemia and ketotic hypoinsulinaemia, and direct investigations to identify the underlying cause. There are, however, many pitfalls that may mislabel healthy individuals as "hypoglycaemic" or misdiagnose treatable or preventable causes of spontaneous hypoglycaemia. Clinical acumen and appropriate investigations will mostly identify hypoglycaemia and its cause.