Glucagon Test Research Articles

7673 Genetic Analysis and Clinical Characterization of Patients with Congenital Hypopituitarism Due to Gene Defects

Abstract Disclosure: T.M. Sasson: None. I.J. Arnhold: None. B.B. Mendonca: None. L.R. Carvalho: None. Introduction: Congenital hypopituitarism is characterized by the deficiency of one or more hormones secreted by the anterior pituitary gland. The genetics of this pathology is complex, and the molecular diagnosis is established in approximately 13% of cases. Objectives: The aim of the present study is to characterize the phenotype harboring pathogenic variants causing congenital hypopituitarism. Methods: Among 393 subjects with congenital hypopituitarism followed up at a tertiary health center, 57 subjects (14,5%) were selected due to a confirmed molecular diagnosis by exome in 9 subjects or by gene panel or Sanger sequencing in 48 subjects. This was a retrospective study where data from medical records, clinical, laboratory and radiological characteristics were analyzed. Results: The most frequent variants identified by sequencing analyzes were in the following genes: PROP1 (29.8%), GH1 (22.8%), GHRHR (15.7%), followed by GLI2, OTX2, HESX1, POU1F1, TGIF1, GHRS, CDH2, SATB1, SOX3 e LZTR1. Consanguinity was reported in 50% of cases, and there was the presence of familial cases of short stature in 60%. The average age at the start of follow-up was 11.1 years (11 SD), 40% of them were male and 52.3% had physical stigmata typical of GH deficiency. Regarding hormonal deficiencies, 27 (47%) had isolated Growth Hormone Deficiency (DGHI) and the others, multiple deficiencies. MRI study of the pituitary gland showed some alteration in 66%, 54% of whom had adenohypophysis hypoplasia and 31% had an ectopic or non-visualized neurohypophysis. From 29 patients with IGF-1 levels available, 28 were below the reference range for sex and age. The serum GH peak after the stimulus test was on average 1.28 ng/mL (1.4SD), of these, only 4 cases had GH peak between 3.3 and 5.0 ng/mL and 1 patient with low IGF-1 and an ectopic neurohypophysis had GH peak of 6.0 ng/mL in a glucagon test. Regarding growth, the initial height in z-score was -4.8 and the average growth at the end of the first year of treatment was 10.7cm, with the average height after this period of Z-3.35. The average of final delta target height (final height Z-score minus the target height Z-score) of patients who underwent hormonal treatment was -0,53 (good response = delta <-1.5). Conclusion: In subjects with congenital hypopituitarism and an established molecular diagnosis, the most frequently affected genes were PROP1 and GH1, the great majority presented a stimulated GH peak < 3.3 ng/mL (only one patient had GH > 5), low basal serum IGF-1 and good increase in growth speed at the end of the first year of treatment with recovery of final height at the end of GH therapy. Presentation: 6/3/2024

Plasma oxytocin levels in response to glucagon in patients with arginine vasopressin deficiency (central diabetes insipidus) and healthy controls

PurposeWe recently demonstrated an additional oxytocin (OT) deficiency in patients with arginine vasopressin (AVP) deficiency (central diabetes insipidus) by using 3,4-methylenedioxy-methamphetamine (MDMA) as a novel provocation test. However, the implication of the MDMA provocation test in clinical practice might be challenging. Glucagon effectively stimulates vasopressinergic neurons with a strong increase in plasma copeptin. We therefore hypothesized that this provocation test might also stimulate OT.MethodsThis is a predefined secondary analysis of a prospective double-blind, randomised, placebo-controlled cross-over trial involving ten patients with AVP deficiency and ten sex- and body-mass index-matched healthy participants at the University Hospital Basel, Switzerland. Each participant underwent the glucagon test (s.c. injection of 1 mg glucagon) and placebo test (s.c. injection of 0.9% normal saline). Plasma OT levels were measured at baseline, 60, 120 and 180 min after injection. The primary objective was to determine whether glucagon stimulates OT and whether OT levels differ between patients with AVP deficiency and healthy participants. The primary outcome (maximum change in OT within 180 min) was compared between groups and conditions using a linear mixed effects model.ResultsIn healthy participants, the median OT at baseline was 82.7 pg/ml [62.3–94.3] and slightly increased to a maximum of 93.3 pg/ml [87.2–121.1] after injection of glucagon, resulting in a change increase of 24.9 pg/ml [5.1–27.8]. Similarly, in patients with AVP deficiency, the median OT at baseline was 73.9 pg/ml [65.3–81.6] and slightly increased after glucagon injection to 114.9 pg/ml [70.9–140.9], resulting in a change increase of 36.8 pg/ml [–2.2 to 51.2]. The results from the mixed model showed no effect between glucagon compared to placebo on OT (difference: –0.5 pg/ml; 95%-CI [–25, 24]; p = 0.97) and no significant treatment-by-group interaction effect between patients compared to healthy participants (interaction: 28 pg/ml; 95%-CI [–7, 62]; p = 0.13).ConclusionWe found no effect of glucagon on plasma OT levels and no difference between patients with AVP deficiency and healthy participants.

Accuracy of Glucagon Testing Across Transition in Young Adults with Childhood-Onset Growth Hormone Deficiency.

The 2019 AACE guidelines suggested peak GH-cutoffs to glucagon test (GST) of ≤3 µg/L and ≤1 µg/L in the diagnosis of permanent GH deficiency (GHD) during the transition phase. Aim of the study was to evaluate the accuracy of GST compared to insulin tolerance test (ITT) in the definition of GHD at adult height achievement. Ninety-seven subjects with childhood-onset GHD (median age, 17.39 years) underwent ITT, GST and IGF-1 testing; 44 subjects were idiopathic (isolated GHD), 35 moderate organic GHD (0-2 hormone deficiencies-HDs) and 18 severe organic GHD (≥3 HDs). Bland and Altman analysis showed a high consistency of GH peak measures after ITT and GST. Receiver operating characteristic analysis-ROC- identified 7.3 μg/L as the optimal GH peak cutoff to GST (95% CI 4.15-8.91; sensitivity 95.7%, specificity 88.2%, positive predictive value-PPV-88.0%, negative predictive value-NPV-95.7%), able to correctly classify 91.8% of the entire cohort while 5.8 μg/L was the best GH peak cutoff able to correctly classify 91.4% of moderate organic GHD patients (95% CI 3.16-7.39; sensitivity 96.0%, specificity 80.0%, PPV 92.3%, NPV 88.9%). Patients with ≥3HDs showed a GH peak <5μg/L at ITT and <5.8μg/L at GST but one. The optimal cutoff for IGF1 was -1.4 SDS (95% CI -1.94-0.77; sensitivity 75%, specificity 94%, PPV 91.7%, NPV 81.0%) that correctly classified 85.1% of the study population. A GH peak to GST <5.8 μg/L represents an accurate diagnostic cutoff for young adults with childhood-onset GHD and high pre-test probability of permanent GHD.

Analiza učestalosti i dužine trajanja kliničke remisije u pacijenata sa novootkrivenim tipom 1 dijabetesa

Introduction: Clinical remission (CR) phase, in other words, euglycaemia, in the absence of insulin therapy (complete CR) or with a reduced daily dose of insulin (partial CR) can be achieved in some patients with new-onset type 1 diabetes (T1D) after the introduction of insulin therapy. Unfortunately, there is still not enough information about the factors influencing the induction and duration of remission. Material and methods: This research included 62 patients with the diagnosis of new-onset T1D, who were treated at the Clinic of Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia in 2019 and 2020. Demographic, clinical and laboratory data were acquired from medical records. Descriptive statistical methods, Fisher's exact probability test, Pearson's chi-square test, Student's t test, Mann Whitney U test and Spearman's correlation coefficient were used for statistical analysis. Results: Clinical remission was inducted in 46.8% of patients and its average duration was 11.2 months. Patients with CR had remarkably lower HbA1c values (9.9 ± 2.8 vs 11.8 ± 2.4%; p=0.007) and lost less weight (4 vs 12 kg, p&lt;0.001) compared to patients without CR. Additionally, C peptide levels at the beginning and 6 minutes after the glucagon test were remarkably higher in patients with CR compared to patients without CR (p&lt;0.001). At the same time, remarkably more patients with CR had autoantibodies detected compared to those without CR (GAD 100% vs 72.4% i IA2-2A 81.8% vs 34.5%; p=0.001). The duration of CR was remarkably correlated with the level of C peptide at the beginning and 6 minutes after the glucagon test (p&lt;0.001). Conclusion: Patients with CR (46.8%) had better metabolic control, less weight loss, better endogenous insulin reserve capacity and less frequent presence of autoantibodies to beta cell antigens at disease onset. At the same time, the duration of CR was associated with an initially better, preserved, endogenous insulin reserve.

Nedostatak hormona rasta kod odraslih - dijagnoza i lečenje

Growth hormone deficiency (GHD) in adults is a rare clinical syndrome with an incidence of 1.4-4.2 per 100,000 persons per year and a prevalence of 350/million. It is characterized by unfavorable body composition, reduced muscle, and bone mass, lower capacity to endure physical effort, abnormal lipid profile, increased cardiovascular risk and poor quality of life. Despite these clinical manifestations, GHD is often unrecognized, so its diagnosis is often missed or delayed. The reason is the non-specific and subtle clinical characteristics, which require the testing of growth hormone (GH) secretion with stimulation tests. Two tests are in use, the insulin tolerance test and the glucagon test, which require the experience of the team performing them. Recently, an oral secretagogue of growth hormone - macimorelin has been used, which is simple test to perform and is safe for the patient. Insufficient secretion of GH in adults can be manifested as isolated or in combination with deficits of other pituitary hormones. However, GH is the most frequently detected hormonal deficit in adults as part of hypopituitarism. Causes of GHD can be congenital or acquired. Congenital reasons are the result of disorders of the embryogenic development of the pituitary gland and hypothalamus, and acquired are the most common complications of tumors of the sellar region and head trauma. Patients with GHD have an increased mortality rate compared to the general population. The causes of the shortened life span of these patients depend on the etiology of hypopituitarism, the applied therapy of tumors of the hypothalamus/pituitary region (surgery, radiotherapy), and the replacement of other missing pituitary hormones. During the last two decades, growth hormone therapy in adults has entered routine clinical practice. The beneficial effects of this substitution are reflected in the body composition, skeletal system, metabolic status, and improvement of the quality of life. GH replacement in adults returns the mortality rate to that expected for age in the general population. Due to the known proliferative, angiogenic, and anti-apoptotic properties of GH, there is still some caution regarding the recurrence of hypopituitarism-causing tumors or the appearance of new tumors during GH replacement. However, large and long-term follow-up studies of adults on GH therapy have shown a high safety profile of this treatment. Daily injections of GH were until recently the only way of its application, and now longacting weekly forms have been marketed, which will significantly improve adherence to this therapy.

SCH772984 ameliorates lipopolysaccharide-induced hypoglycemia in mice through reversing MEK/ERK/Foxo1-mediated gluconeogenesis suppression.

Lipopolysaccharide (LPS) results in a lethal hypoglycemic response. However, the main molecular mechanism involved in LPS-induced glucose metabolism disorder is poorly understood. This study intends to investigate the signaling pathways involved in LPS-induced hypoglycemia and potential efficacy of extracellular signal-regulated kinase (ERK) inhibitor SCH772984. The effects of LPS and SCH772984 on gluconeogenesis, glucose absorption, and glycogenolysis were evaluated by pyruvate tolerance test, oral glucose tolerance test, and glucagon test, respectively. After a single intraperitoneal injection of 0.5mg/kg LPS, the mice's blood glucose levels and gluconeogenesis ability were significantly lower than that of control group. Besides, mRNA and protein expression of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) decreased significantly after LPS treatment. LPS induced the phosphorylation of ERK1/2, MEK1/2 (mitogen-activated protein kinase), and Foxo1 while inhibited Foxo1 expression in the nucleus, indicating an important role of the MEK/ERK/Foxo1 signaling in the inhibition of gluconeogenesis by LPS. Furthermore, SCH772984 elevated blood glucose, increased the G6Pase and PEPCK expression, and inhibited pERK1/2 and pFoxo1 expression in LPS-induced mice. In summary, LPS inhibited gluconeogenesis and induced hypoglycemia through the MEK/ERK/Foxo1 signal pathway, and ERK inhibitor could effectively reverse decreased blood glucose in mice with LPS treatment. These findings provide a novel therapeutic target for LPS-induced hypoglycemia.

THU172 Accuracy Of The Glucagon Testing In The Diagnosis Of Growth Hormone Deficiency During Transition

Abstract Disclosure: N. Di Iorgi: None. D. Guglielmi: None. N. Flavia: None. A. Allegri: None. D. Fava: None. E. Casalini: None. G. Patti: None. M. Maghnie: None. Objectives: To evaluate the accuracy of the Glucagon test (GST) compared with the Insulin Tolerance test (ITT) as the gold standard in the diagnosis of Growth Hormone deficiency (GHD) in young adults with childhood-onset GHD (COGHD). Methods: Eighty-six subjects with COGHD (33F, 55M) were evaluated by ITT and GST stimulation tests and IGF-1 SDS at adult height achievement (median age of 17.5; IQR 13.9-18.4 years). Subjects were recruited from a single Center and based on the AACE 2019 Guidelines [1] classified as 1. idiopathic isolated GHD (I-GHD n=40 with normal brain MRI); 2. organic moderate GHD (omGHD with less than 3 pituitary deficiencies-PD and IGF-1&amp;lt;0 SDS, total n=40; n=12 midline defects, n=2 ALL, n=26 CNS tumors); 3. congenital/genetic defects/organic severe GHD (osGHD ≥3 PD and IGF-1 &amp;lt;-2 SDS, total n=6; n=1 midline defect, n=5 CNS tumors). ROC analyses were performed in order to analyze the Sensitivity (Se) and Specificity (Sp) of the GH peak after GST and of IGF-1 SDS compared to ITT. A peak GH value &amp;lt;6μg/L after ITT was suggestive of permanent GHD [2]. Results: Median GH peak to ITT (0.2; IQR 0.01-0.7 μg/L) and GST (0.1; IQR 0.01-1.4μg/L) were lower in osGHD compared to I-GHD subjects (15.0; IQR 8.6-21.9 to ITT and 12.6; IQR 10.5-18.8 μg/L to GST, P’s &amp;lt;0.0001); similarly, GH peak to ITT (2.1; IQR 1.1-6.8 μg/L) and GL (2.7; IQR 1.2-5.8) were lower in omGHD compared to I-GHD subjects (P’s &amp;lt;0.0001). Mean IGF-1 were also lower in osGHD (-3.2 SDS; IQR -7.4- -2.9, P&amp;lt;0.0001) and in omGHD (-2.0 SDS; IQR -2.8 - -0.7; P&amp;lt;0.0001) compared to I-GHD subjects (0,1; IQR -0.6-1.1SDS). A GH peak value to GST of 7.59 mcg/L (Se 92.3%, Sp of 87.2%; AUC=0.94; 95% CI, 0.89-0.99) correctly classified 89.5% of the entire cohort while an IGF-1 cut-off of -1.45 SDS (Se 73%; Sp 93.5%; AUC=0.84; 95% CI, 0.75 - 0.94) correctly classified 83,1%. A GH peak value to GST of 5.81 mcg/L (Se 96.6%, Sp of 81.8%; AUC=0.95; 95% CI, 0.88-1.02) correctly classified 92.5% of omGHD patients while an IGF-1 cut-off of -1.64 SDS (Se 72.3%, Sp of 90.9%; AUC=0.94; 95% CI, 0.89-0.99) correctly classified 77.5% omGHD patients. Median BMI SDS was higher in patients with osGHD (1.8; IQR 1,6- 2.2, P&amp;lt;0.001) and omGHD (0.6; IQR 0.1- 1.8, P&amp;lt;0.001) compared to I-GHD (0.2; IQR -0.7- 1.1). GH peak to GST correlated with BMI SDS only in the total cohort (r -0.313, P=0.0031). Conclusions: Our results suggest that a peak value &amp;lt;6 μg/L after GST is accurate in detecting permanent GHD during transition in a cohort of patients with organic GHD with less than 3 pituitary defects and IGF-1 values &amp;lt;0 SDS; the GH response to GST could be affected by BMI SDS, but further studies are needed. [1] Yuen KCJ et al. Endocr Pract 2019; 25 (11):1191-1232. [2] Maghnie M et al, EJE 2005; 152:589-596. Presentation: Thursday, June 15, 2023

The efficacy of switching basal-bolus insulin therapy to basal insulin-supported oral therapy with a glinide and an α-glucosidase inhibitor in patients with type 2 diabetes depends on insulin secretory capacity, but not on blood glucose profiles and insulin dosages prior to the switching.

We aimed to identify patients who would benefit from basal insulin-supported oral therapy (BOT) with a glinide and an α-glucosidase inhibitor (a fixed-dose combination tablet of mitiglinide 10mg and voglibose 0.2mg) in Japanese type 2 diabetic patients. Patients who were hospitalized to improve hyperglycemia received basal-bolus insulin therapy. After the reduction of glucose toxicity, a 75g oral glucose tolerance test and a glucagon test were performed. Thereafter, the basal-bolus insulin therapy was switched to BOT with mitiglinide, followed by further addition of voglibose. Interstitial glucose levels were continuously monitored throughout the study period. Diurnal glucose profile was recorded and analyzed. Patients were divided into two groups according to whether their percentage of time in range (TIR, 70-180mg/dL) under BOT with mitiglinide/voglibose was higher than 70% or not, and the differences in clinical characteristics between the groups were analyzed. Twenty patients were enrolled, and 19 of them completed the study. BOT with mitiglinide/voglibose achieved ≥ 70% of TIR in thirteen patients. The area under the curve of serum C-peptide levels during the oral glucose tolerance test was significantly higher in the patients with ≥ 70% of TIR. The daily insulin dosages and blood glucose profiles were comparable between the two groups. The efficacy of BOT with mitiglinide/voglibose depended on residual insulin secretory abilities. This therapy would be a useful therapeutic option for patients with type 2 diabetes.

A 1-year pilot study of intralymphatic injections of GAD-alum in individuals with latent autoimmune diabetes in adults (LADA) with signs of high immunity: No safety concerns and resemblance to juvenile type 1 diabetes.

To test, for the first time in latent autoimmune diabetes in adults (LADA), the effects of autoantigen-specific immunotherapy by intralymphatic administration of aluminium-formulated recombinant human glutamic acid decarboxylase 65 (GAD-alum); specifically, to test if this treatment is safe, to test whether it induces a strong immunological response akin to a similar protocol in type 1 diabetes and to look for associations with preserved beta-cell function. Three GAD-alum injections, 4 μg each, were administered 1 month apart into an inguinal lymph node in 14 people with newly diagnosed LADA (age 30-62 years) presenting with high levels of antibodies against glutamic acid decarboxylase (GADA). Adverse effects, immunological variables and beta-cell function were monitored, with detailed measurements at 5 and 12 months from baseline. Clinical adverse effects were minor and transient and measured laboratory variables were unaffected. All participants completed the study. Treatment raised levels of GADA, elicited strong effects on reactivity of peripheral blood mononuclear cells to GAD and raised cytokine/chemokine levels. Beta-cell function appeared stable preferentially in the seven participants carrying human leukocyte antigen (HLA) haplotypes DR3DQ2, as assessed by C-peptide glucagon tests (P < 0.05 vs. seven non-carriers). Intralymphatic treatment with GAD-alum in LADA is without clinical or other safety concerns over a 12-month period. As in a similar protocol used in type 1 diabetes, treatment exerts a strong immunological impact and is compatible with protection of beta-cell function preferentially in HLA-DR3DQ2 LADA patients. These findings pave the way for a randomized controlled trial in this important subgroup of LADA patients.

RF02 | PMON323 Pituitary stalk interruption syndrome, polydactyly, polymicrogyria and a ZRSR2 variant

Abstract Background Pituitary stalk interruption syndrome (PSIS) may associate with brain midline defects and also with polydactyly (GLI2 mutations) but rarely with brain cortex anomalies. Clinical Case We report a boy referred at age 19 months because of growth failure. Bilateral postaxial polydactyly, syndactyly of the toes, and a nodule on the tongue were noted at term birth. The neonatal course was complicated by marked but transient hypoglycemia. During infancy, the acquisition of gross motor skills was slightly delayed. Upon referral, body length was 4.1 SD below the level of mid-parental height. Extremely low concentrations of circulating IGF-I (8 mcg/L) and IGFBP-3 (861 mcg/L) were suggestive of growth hormone (GH) deficiency which was corroborated by glucagon test (peak GH 3.3 mcg/L, peak cortisol 14.6 mcg/dL) in an euthyroid and normoprolactinemic state, and in the absence of polydipsia or polyuria. Brain MRI disclosed not only a PSIS triad (with a virtual absence of the pituitary stalk and the anterior pituitary, and with an ectopic position of the posterior pituitary) but also abnormal sulcation and polymicrogyria (pointing to abnormal lamination in the cortex) on both sides in the posterior cingulum. Familial history is positive for holoprosencephaly and polydactyly in two male relatives, who died neonatally. Whole exome sequencing showed a rare maternally inherited variant in ZRSR2 on the X chromosome (c. 1207_1208delAG (p.Arg403Glyfs*24)) (OMIM 300028). ZRSR2 isdepleted from loss-of-function variants in the reference population, and has not been associated with congenital anomalies or with pituitary dysfunction. This ZRSR2 variant escapes nonsense mediated decay and segregates in this family according to an X-linked recessive pattern. X-inactivation studies and gene expression studies are ongoing to correlate the ZRSR2 variant to the patient's phenotype. Conclusion This case describes a toddler with polydactyly and short stature, based on GH deficiency due to PSIS, in combination with polymicrogyria. Studies are ongoing to link the patient's phenotype to a rare variant in ZRSR2. Presentation: Saturday, June 11, 2022 1:30 p.m. - 1:35 p.m., Saturday, June 11, 2022 1:30 p.m. - 1:35 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

ODP313 Glucagon-Stimulated Copeptin Measurements in the Differential Diagnosis of Diabetes Insipidus: A Double-Blind Randomized Placebo-Controlled Study

Abstract Background The differential diagnosis of diabetes insipidus and primary polydipsia is challenging. To date, the most reliable approaches are copeptin measurement after hypertonic saline infusion or arginine, which is a known growth hormone secretagogue but has recently also been shown to stimulate the neurohypophysis. Similar to arginine, glucagon is also known to stimulate growth hormone release, but its effect on the neurohypophysis unknown. Methods In this double-blind, randomized, placebo-controlled trial, we enrolled 22 healthy participants, 10 patients with central diabetes insipidus and 10 patients with primary polydipsia at the University Hospital Basel. Each participant underwent the glucagon test, i. e., subcutaneous injection of 1mg glucagon, and placebo test, i. e., subcutaneous injection of 1 ml 0.9% sodium. Plasma copeptin levels were measured at baseline and 30, 60, 90, 120, 150, 180 minutes after injection. The primary objective was to determine whether glucagon stimulates copeptin and to explore whether the copeptin response differentiates between diabetes insipidus and primary polydipsia. Findings: The median (IQR) age of all participants was 27 years (23; 32), 59% were female. In healthy participants, glucagon injection stimulated copeptin with a median (IQR) increase of 7.56 (2.38; 28. 03) pmol/l, while placebo had no effect (0.10pmol/l (-0.70; 0.68); difference: 7.67 (1.98, 27. 09) pmol/l, p &amp;lt; 0. 001). In patients with central diabetes insipidus, copeptin showed no relevant increase after glucagon injection, with an increase of 0.55pmol/l (0.21; 1.65), whereas copeptin was stimulated in patients with primary polydipsia with an increase of 15.70 (5.99; 24.39) pmol/l. Using a copeptin cutoff level of 4.6pmol/l had a sensitivity of 100% (95%CI 100-100) and a specificity of 90% (95%CI 70-100) to discriminate between diabetes insipidus and primary polydipsia. Interpretation: Glucagon stimulates the neurohypophysis, and glucagon-stimulated plasma copeptin has the potential to be used for a safe, novel, and precise test in the differential diagnosis of polyuria-polydipsia syndrome. Presentation: No date and time listed

Lipid droplet accumulation in β cells in patients with type 2 diabetes is associated with insulin resistance, hyperglycemia and β cell dysfunction involving decreased insulin granules.

Background and objectivePancreatic fat is a form of ectopic fat. Lipid droplets (LDs) are also observed in β cells; however, the pathophysiological significance, especially for β cell function, has not been elucidated. Our aim was to assess LD accumulation in β cells in various stages of glucose intolerance and to clarify its relationship with clinical and histological parameters.MethodsWe examined 42 Japanese patients who underwent pancreatectomy. The BODIPY493/503-positive (BODIPY-positive) area in β cells was measured in pancreatic sections from 32 patients. The insulin granule numbers were counted in an additional 10 patients using electron microscopy.ResultsThe BODIPY-positive area in β cells in preexisting type 2 diabetes patients was higher than that in normal glucose tolerance patients (p = 0.031). The BODIPY-positive area in β cells was positively correlated with age (r = 0.45, p = 0.0097), HbA1c (r = 0.38, p = 0.0302), fasting plasma glucose (r = 0.37, p = 0.045), and homeostasis model assessment insulin resistance (r = 0.41, p = 0.049) and negatively correlated with an increase in the C-peptide immunoreactivity level by the glucagon test (r = -0.59, p = 0.018). The ratio of mature insulin granule number to total insulin granule number was reduced in the patients with rich LD accumulation in β cells (p = 0.039).ConclusionsType 2 diabetes patients had high LD accumulation in β cells, which was associated with insulin resistance, hyperglycemia, aging and β cell dysfunction involving decreased mature insulin granules.

Hyperinsulinism May Be Underreported in Hypoglycemic Patients with Phosphomannomutase 2 Deficiency

Objective:Phosphomannomutase 2 deficiency (PMM2-CDG) is a disorder of protein N-glycosylation with a wide clinical spectrum. Hypoglycemia is rarely reported in PMM2-CDG. In this study, we evaluated cause, treatment options and outcomes in cases with hypoglycemia in the course of PMM2-CDG.Methods:Clinical records of patients followed with PMM2-CDG within the last two decades were reviewed. Medical data of patients with hypoglycemia were evaluated in more detail. Demographic and clinical findings, organ involvement and laboratory investigations at time of hypoglycemia were recorded. Time of first attack of hypoglycemia, cause, treatment modalities, duration of hypoglycemia (permanent/transient), and duration of treatment, as well as outcome were also recorded. Other published cases with PMM2-CDG and hypoglycemia are also reviewed in order to elucidate characteristics as well as pathophysiology of hypoglycemia.Results:Nine patients with PMM2-CDG were reviewed, and hypoglycemia was present in three cases. All three had hyperinsulinism as the cause of hypoglycemia. In the first two cases reported here, serum insulin level concurrent with hypoglycemic episodes was elevated, and glucose response was exaggerated during glucagon test, favoring hyperinsulinism. However, in the third case, the serum insulin level at time of hypoglycemia was not so high but hypoglycemia responded well to diazoxide. Hyperinsulinism was permanent in two of these three cases. No genotype-phenotype correlation was observed with respect to hyperinsulinism.Conclusion:The main cause of hypoglycemia in PMM2-CDG appears to be hyperinsulinism. Although insulin levels at the time of hypoglycemia may not be very high, hypoglycemia in patients with PMM2 responds well to diazoxide.

Use of expert consensus to improve the diagnosis and management of type 1 diabetes mellitus.

Although type 1 diabetes mellitus (T1DM) is recognized as a catastrophic disease among the different types of diabetes, it is often confusedly diagnosed in clinical practice and difficult in care. The objective of this study is to reach a multidisciplinary consensus for the establishment of clinical recommendations on T1DM to optimize its undoubtedly diagnostic evaluation and transitional care. Scientific evidence was reviewed by a committee of researchers, based on which recommendations related to T1DM diagnosis were formulated. A two-round method was conducted to compare the opinions of a panel of 32 specialists (adult endocrinologists [53.1%], pediatric endocrinologists [43.8%], a diabetes educator for child and adolescent [3.1%]) on these issues. The panel reached consensus on two of the six items discussed. The four items on which no consensus was reached were related to autoantibody detection and age of onset. Up to 80% of the panelists favored items related to the glucagon test and diabetic ketoacidosis history for T1DM diagnosis. Consensus regarding transitional care through diabetes educators was established. The assessment conducted by experts on T1DM showed a high level of professional agreement regarding the proposed diagnostic and transitional care recommendations. A comprehensive analysis of the latest evidence is warranted for the items on which consensus was not established.

Glucagon-stimulated copeptin measurements in the differential diagnosis of diabetes insipidus: a double-blind, randomized, placebo-controlled study.

The differential diagnosis of diabetes insipidus is challenging. The most reliable approaches are copeptin measurements after hypertonic saline infusion or arginine, which is a known growth hormone secretagogue but has recently also been shown to stimulate the neurohypophysis. Similar to arginine, glucagon stimulates growth hormone release, but its effect on the neurohypophysis is poorly studied. Double-blind, randomized, placebo-controlled trial including 22 healthy participants, 10 patients with central diabetes insipidus, and 10 patients with primary polydipsia at the University Hospital Basel, Switzerland. Each participant underwent the glucagon test (s.c. injection of 1 mg glucagon) and placebo test. The primary objective was to determine whether glucagon stimulates copeptin and to explore whether the copeptin response differentiates between diabetes insipidus and primary polydipsia. Copeptin levels were measured at baseline, 30, 60, 90, 120, 150, and 180 min after injection. In healthy participants, glucagon stimulated copeptin with a median increase of 7.56 (2.38; 28.03) pmol/L, while placebo had no effect (0.10 pmol/L (-0.70; 0.68); P < 0.001). In patients with diabetes insipidus, copeptin showed no relevant increase upon glucagon, with an increase of 0.55 (0.21; 1.65) pmol/L, whereas copeptin was stimulated in patients with primary polydipsia with an increase of 15.70 (5.99; 24.39) pmol/L. Using a copeptin cut-off level of 4.6pmol/L had a sensitivity of 100% (95% CI: 100-100) and a specificity of 90% (95% CI: 70-100) to discriminate between diabetes insipidus and primary polydipsia. Glucagon stimulates the neurohypophysis, and glucagon-stimulated copeptin has the potential for a safe, novel, and precise test in the differential diagnosis of diabetes insipidus.

Glucagon Test Is a Useful Predictor of Withdrawal From Insulin Therapy in Subjects With Type 2 Diabetes Mellitus.

There are many tests for evaluating endogenous insulin secretory capacity. However, there are only a limited number of studies that have examined in detail in clinical practice which method most accurately reflects the ability to secrete endogenous insulin especially in hyperglycemic state. The purpose of this study was to find the endogenous insulin secretory capacity and a possible predictor of insulin withdrawal in subjects with type 2 diabetes requiring hospitalization due to hyperglycemia. In the endogenous insulin secretory test during hospitalization, CPR, CPR index, and ΔCPR after glucagon loading were all significantly higher in the insulin withdrawal group. On the other hand, there were no difference in fasting CPR index, HOMA-β, SUIT, and 24-hour urinary CPR excretion between the two groups. In the glucagon test of the insulin withdrawal group, the cutoff value of ΔCPR was 1.0 ng/mL, the withdrawal rate of ΔCPR of 1.0 ng/mL or more was 69.2%, and the withdrawal rate of less than 1.0 ng/mL was 25.0%. In conclusion, it is likely that glucagon test is the most powerful tool for predicting the possibility of insulin withdrawal as well as for evaluating endogenous insulin secretory capacity in subjects with type 2 diabetes requiring hospitalization due to hyperglycemia.

Hyperinsulinism may be Underreported in Hypoglycemic Patients with Phosphomannomutase 2 Deficiency

Phosphomannomutase 2 deficiency (PMM2-CDG) is a disorder of protein N-glycosylation with a wide clinical spectrum. Hypoglycemia is rarely reported in PMM2-CDG. In this study, we evaluated cause, treatment options and outcomes in cases with hypoglycemia in the course of PMM2-CDG. Clinical records of patients followed with PMM2-CDG within the last two decades were reviewed. Medical data of patients with hypoglycemia were evaluated in more detail. Demographic and clinical findings, organ involvement and laboratory investigations at time of hypoglycemia were recorded. Time of first attack of hypoglycemia, cause, treatment modalities, duration of hypoglycemia (permanent/transient), and duration of treatment, as well as outcome were also recorded. Other published cases with PMM2-CDG and hypoglycemia are also reviewed in order to elucidate characteristics as well as pathophysiology of hypoglycemia. Nine patients with PMM2-CDG were reviewed, and hypoglycemia was present in three cases. All three had hyperinsulinism as the cause of hypoglycemia. In the first two cases reported here, serum insulin level concurrent with hypoglycemic episodes was elevated, and glucose response was exaggerated during glucagon test, favoring hyperinsulinism. However, in the third case, the serum insulin level at time of hypoglycemia was not so high but hypoglycemia responded well to diazoxide. Hyperinsulinism was permanent in two of these three cases. No genotype-phenotype correlation was observed with respect to hyperinsulinism. The main cause of hypoglycemia in PMM2-CDG appears to be hyperinsulinism. Although insulin levels at the time of hypoglycemia may not be very high, hypoglycemia in patients with PMM2 responds well to diazoxide.

A Patient With Ketosis-prone Diabetes Whose Pancreatic Endocrine Level Was Evaluated by Glucagon and Arginine Load Tests

A Patient With Ketosis-prone Diabetes Whose Pancreatic Endocrine Level Was Evaluated by Glucagon and Arginine Load Tests

Stress hyperglycemia as first sign of asymptomatic type 1 diabetes: an instructive case

BackgroundStress hyperglycemia (SH) is considered a transient manifestation and routine diagnostic evaluation was thought to be unnecessary due to the lack of definite correlation with diabetes mellitus (DM). Although SH was usually benign and long-term treatment was superfluous, it might be the first sign of insulinopenic status such as type 1 DM (T1DM).Case presentationWe reported a boy with acute asthma attack presented incidentally with high blood glucose levels exceeding 300 mg/dL and obvious glycemic variability. A prolonged hyperglycemic duration of more than 48 h was also noticed. To elucidate his unique situation, glucagon test and insulin autoantibody survey were done which showed insulinopenia with positive anti-insulin antibody and glutamic acid decarboxylase antibody despite the absence of overt DM symptoms and signs.ConclusionsThis case highlights that SH might be a prodromal presentation in T1DM children, especially when accompanied simultaneously with extreme hyperglycemia, apparent glucose variability, as well as prolonged hyperglycemic duration.

Comparative analysis of the methods for differential diagnosis of non-diabetic hypoglycemia (NDH): Beta-hydroxybutyrate and glucagon test

Comparative analysis of the methods for differential diagnosis of non-diabetic hypoglycemia (NDH): Beta-hydroxybutyrate and glucagon test