Permanent neonatal diabetes (PND) can be caused by mutations in the transcription factors insulin promoter factor (IPF)-1, eukaryotic translation initiation factor-2␣ kinase 3 (EIF2AK3), and forkhead box-P3 and in key components of insulin secretion: glucokinase (GCK) and the ATP-sensitive K؉ channel subunit Kir6.2. We sequenced the gene encoding Kir6.2 (KCNJ11) in 11 probands with GCK-negative PND. Heterozygous mutations were identified in seven probands, causing three novel (F35V, Y330C, and F333I) and two known (V59M and R201H) Kir6.2 amino acid substitutions. Only two probands had a family history of diabetes. Subjects with the V59M mutation had neurological features including motor delay. Three mutation carriers tested had an insulin secretory response to tolbutamide, but not to glucose or glucagon. Glibenclamide was introduced in increasing doses to investigate whether sulfonylurea could replace insulin. At a glibenclamide dose of 0.3-0.4 mg ⅐ kg ؊1 ⅐ day ؊1 , insulin was discontinued. Blood glucose did not deteriorate, and HbA 1c was stable or fell during 2-6 months of follow-up. An oral glucose tolerance test performed in one subject revealed that glucose-stimulated insulin release was restored. Mutations in Kir6.2 were the most frequent cause of PND in our cohort. Apparently insulin-dependent patients with mutations in Kir6.2 may be managed on an oral sulfonylurea with sustained metabolic control rather than insulin injections, illustrating the principle of pharmacogenetics applied in diabetes treatment. Diabetes 53: [2713][2714][2715][2716][2717][2718] 2004 N eonatal diabetes may be defined as hyperglycemia diagnosed within the first 3 months of life (1). Transient neonatal diabetes is associated with abnormalities in chromosome 6 (2), whereas the permanent form may be caused by mutations in the genes encoding the transcription factors insulin promoter factor (IPF)-1 (3,4), eukaryotic translation initiation factor-2␣ kinase 3 (EIF2AK3) (5), forkhead box-P3 (6), and the glucose-sensing enzyme glucokinase (GCK) (7,8). Gloyn et al. (9) recently identified that the ATPsensitive K ϩ channel subunit Kir6.2 can cause PND. We here report nine new cases of PND associated with mutations in the gene KCNJ11 encoding Kir6.2. In addition, we also show that oral therapy with a sulfonylurea drug should be considered in patients with mutations in Kir6.2. RESEARCH DESIGN AND METHODSThe neither systematic nor population-based screening included 16 referred probands with PND from Norway, Israel, Italy, Turkey, and the U.S. (8,10). Informed consent was obtained from the subjects or their parents. The studies were performed according to the Declaration of Helsinki and approved by ethics committees. Genetic studies. KCNJ11 encoding Kir6.2 was sequenced as previously described (9). Microsatellite markers localized to four different chromosomes were used to confirm family relationships. Clinical studies. A common protocol was carried out for all participating centers. The medical records of mutation carriers were reviewed ...
SummaryBackgroundKCNJ11 mutations cause permanent neonatal diabetes through pancreatic ATP-sensitive potassium channel activation. 90% of patients successfully transfer from insulin to oral sulfonylureas with excellent initial glycaemic control; however, whether this control is maintained in the long term is unclear. Sulfonylurea failure is seen in about 44% of people with type 2 diabetes after 5 years of treatment. Therefore, we did a 10-year multicentre follow-up study of a large international cohort of patients with KCNJ11 permanent neonatal diabetes to address the key questions relating to long-term efficacy and safety of sulfonylureas in these patients.MethodsIn this multicentre, international cohort study, all patients diagnosed with KCNJ11 permanent neonatal diabetes at five laboratories in Exeter (UK), Rome (Italy), Bergen (Norway), Paris (France), and Krakow (Poland), who transferred from insulin to oral sulfonylureas before Nov 30, 2006, were eligible for inclusion. Clinicians collected clinical characteristics and annual data relating to glycaemic control, sulfonylurea dose, severe hypoglycaemia, side-effects, diabetes complications, and growth. The main outcomes of interest were sulfonylurea failure, defined as permanent reintroduction of daily insulin, and metabolic control, specifically HbA1c and sulfonylurea dose. Neurological features associated with KCNJ11 permanent neonatal diabetes were also assessed. This study is registered with ClinicalTrials.gov, number NCT02624817.Findings90 patients were identified as being eligible for inclusion and 81 were enrolled in the study and provided long-term (>5·5 years cut-off) outcome data. Median follow-up duration for the whole cohort was 10·2 years (IQR 9·3–10·8). At most recent follow-up (between Dec 1, 2012, and Oct 4, 2016), 75 (93%) of 81 participants remained on sulfonylurea therapy alone. Excellent glycaemic control was maintained for patients for whom we had paired data on HbA1c and sulfonylurea at all time points (ie, pre-transfer [for HbA1c], year 1, and most recent follow-up; n=64)—median HbA1c was 8·1% (IQR 7·2–9·2; 65·0 mmol/mol [55·2–77·1]) before transfer to sulfonylureas, 5·9% (5·4–6·5; 41·0 mmol/mol [35·5–47·5]; p<0·0001 vs pre-transfer) at 1 year, and 6·4% (5·9–7·3; 46·4 mmol/mol [41·0–56·3]; p<0·0001 vs year 1) at most recent follow-up (median 10·3 years [IQR 9·2–10·9]). In the same patients, median sulfonylurea dose at 1 year was 0·30 mg/kg per day (0·14–0·53) and at most recent follow-up visit was 0·23 mg/kg per day (0·12–0·41; p=0·03). No reports of severe hypoglycaemia were recorded in 809 patient-years of follow-up for the whole cohort (n=81). 11 (14%) patients reported mild, transient side-effects, but did not need to stop sulfonylurea therapy. Seven (9%) patients had microvascular complications; these patients had been taking insulin longer than those without complications (median age at transfer to sulfonylureas 20·5 years [IQR 10·5–24·0] vs 4·1 years [1·3–10·2]; p=0·0005). Initial improvement was noted following transfer to sulfo...
ABSTRACT.Background. There is an increase in the incidence of type 2 diabetes in children and adolescents. Absence of known diabetes autoimmune markers is sometimes required to confirm the diagnosis.Objective. To identify clinical and autoimmune characteristics of type 2 diabetes in a pediatric population.Method. We report an analysis of 48 children and adolescents with type 2 diabetes, compared with 39 randomly selected children with type 1 diabetes, diagnosed and followed at the Loma Linda University Pediatric Diabetes Center. Ethnic, familial, seasonal, and autoimmune marker characteristics are outlined. To determine the reliability of antibody testing in confirming the type of diabetes at diagnosis, we studied the incidence of positive islet cell antibodies (ICAs), glutamic acid decarboxylase antibodies (GADs), and insulin autoantibodies (IAAs) at diagnosis in both groups. ICA512, GADs, and IAAs were measured by radioimmunoassay.Results. The cohort with type 2 diabetes had a similar gender distribution as the group with type 1 diabetes but a significantly higher age at diagnosis. Ethnic background was significantly different between the 2 groups, predominantly Hispanic in type 2 and white in type 1. Body mass index was significantly higher in type 2 diabetes (mean ؍ 31.24 kg/m 2 ). Among the patients with type 2 diabetes, 33% presented in diabetic ketoacidosis, random blood glucose at diagnosis ranged from 11.4 to 22.25 mmol/L (228 -445 mg/dL), fasting C-peptide levels ranged from 0.89 to 2.7 nmol/L (2.7-8.2 ng/mL; normal: <1.36 nmol/L), and hemoglobin A 1C was 10.8 ؎ 3.5% (normal: <6.6%). None of these parameters was significantly different from the type 1 diabetes group. Although the incidence of diabetes antibody markers was significantly lower in type 2 versus type 1 diabetes, 8.1% of patients with type 2 diabetes had positive ICAs, 30.3% had positive GADs, and 34.8% had positive IAAs without ever being treated with insulin. In the type 2 diabetes group, none of the Hispanic patients had ICAs. However, there was no significant correlation between any of the diabetes antibodies and obesity, presence of acanthosis nigricans, or family history of diabetes. The frequency of thyroid antibodies was not significantly different from the group with type 1 diabetes. Daily insulin requirements 1 year after diagnosis were significantly lower in type 2 diabetes, ranging from 0 to 1.2 U/kg with a mean of 0.33. Conclusion.Absence of diabetes autoimmune markers is not a prerequisite for the diagnosis of type 2 diabetes in children and adolescents. Pediatrics 2001;107(6). URL: http://www.pediatrics.org/cgi/content/full/107/6/ e102; type 2 diabetes, adolescents, autoimmunity, islet cell antibodies, glutamic acid decarboxylase antibodies.
To determine the characteristics of pediatric liver transplant recipients who develop GI and/or PTDM, data on children undergoing their first liver transplant from the SPLIT database were analyzed (n = 1611). Recipient and donor characteristics that were evaluated included age at transplant, gender, race, primary disease, hospitalization status at transplant, BMI, recipient and donor CMV status, donor type, donor age, and primary immunosuppression. GI/PTDM was found in 214 individuals (13%) of whom 166 (78%) were diagnosed within 30 days of transplantation (early GI/PTDM). Multivariate analyses suggests that age >5 yr at transplant, hospitalization at transplant, a primary diagnosis other than BA, early steroid use, and tacrolimus use are associated with increased incidence of early GI. Routine monitoring for the development of GI and post-transplant diabetes is indicated in the short- and long-term care of children after liver transplantation.
More than half of transplanted b -cells undergo apoptotic cell death triggered by nonimmunological factors within a few days after transplantation. To investigate the dynamic hypoxic responses in early transplanted islets, syngeneic islets were transplanted under the kidney capsule of balb/c mice. Hypoxiainducible factor-1a (HIF-1a ) was strongly expressed at post-transplant day (POD) 1, increased on POD 3, and gradually diminished on POD 14. Insulin secretion decreased on POD 3 in association with a significant increase of HIF-1a -related b -cell death, which can be suppressed by short-term hyperbaric oxygen therapy. On POD 7, apoptosis was not further activated by continually produced HIF-1a . In contrast, improvement of nerve growth factor and duodenal homeobox factor-1 (PDx-1) production resulted in islet graft recovery and remodeling. In addition, significant activation of vascular endothelial growth factor in islet grafts on POD 7 correlated with development of massive newly formed microvessels, whose maturation is advanced on POD 14 with gradual diminution of HIF-1a . We conclude that (1) transplanted islets strongly express HIF-1a in association with b -cell death and decreased insulin production until adequate revascularization is established and (2) early suppression of HIF-1a results in less b -cell death thereby minimizing early graft failure.
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