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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...

Congenital adrenal hyperplasia (CAH), resulting from mutations in CYP11B1, a gene encoding 11β-hydroxylase, represents a rare autosomal recessive Mendelian disorder of aberrant sex steroid production. Unlike CAH caused by 21-hydroxylase deficiency, the disease is far more common in the Middle East and North Africa, where consanguinity is common often resulting in identical mutations. Clinically, affected female newborns are profoundly virilized (Prader score of 4/5), and both genders display significantly advanced bone ages and are oftentimes hypertensive. We find that 11-deoxycortisol, not frequently measured, is the most robust biochemical marker for diagnosing 11β-hydroxylase deficiency. Finally, computational modeling of 25 missense mutations of CYP11B1 revealed that specific modifications in the heme-binding (R374W and R448C) or substrate-binding (W116C) site of 11β-hydroxylase, or alterations in its stability (L299P and G267S), may predict severe disease. Thus, we report clinical, genetic, hormonal, and structural effects of CYP11B1 gene mutations in the largest international cohort of 108 patients with steroid 11β-hydroxylase deficiency CAH.steroid hormones | missense mutations | classic CAH | ambiguous genitalia C ongenital adrenal hyperplasia (CAH) is a Mendelian disorder transmitted as an autosomal recessive trait. The most prevalent form of CAH arises from steroid 21-hydroxylase enzyme deficiency, accounting for ∼90-95% of all cases (1, 2). In contrast, CAH caused by steroid 11β-hydroxylase deficiency is considerably rare, with a prevalence of 5-8% (3), from which we estimate an overall frequency of 1 in 100,000 live births.Two homologous enzymes, 11β-hydroxylase and aldosterone synthase, are encoded by the CYP11B1 and CYP11B2 genes, respectively. The two genes are 40-kb apart, each comprising nine exons and mapped to chromosome 8q21-22 (3, 4) (Fig. 1A). In contrast to CYP21A2 and its CYP21A1P pseudogene, CYP11B1 and CYP11B2 are both active and do not have a pseudogene. The two encoded homologs, however, have distinct functions in cortisol and aldosterone synthesis, respectively (3). In the zona fasciculata, 11β-hydroxylase converts 11-deoxycortisol and 11-deoxycorticosterone to cortisol and corticosterone, respectively, and is regulated by adrenocorticotropic hormone secreted by the pituitary. In contrast, in the zona glomerulosa aldosterone synthase converts corticosterone to aldosterone with the intermediate production of 18-hydroxycorticosterone. These latter conversions are controlled mainly by the renin angiotensin II system and serum potassium concentration (3).Deficiency of 11β-hydroxylase prevents the conversion of 11-deoxycortisol to cortisol and 11-deoxycorticosterone to corticosterone. This results in high levels of 11-deoxycortisol and 11-deoxycorticosterone, respectively, which are shunted into the androgen synthesis pathway, resulting in high levels of the androgenic steroid, androstenedione. Female newborns are thus profoundly virilized and exhibit significant masculinization of the ex...

Young adult survivors of childhood cancer have reduced BMD. Because age at study coincides with the normal age of attainment of peak bone mass and peak bone mass is a major determinant of BMD later in life, many of these patients are at increased risk for osteoporosis and fractures.

The purpose of this study was to assess the performance and acceptability of a blood glucose meter coupled with a gaming system for children, adolescents, and young adults with type 1 diabetes. During an in-clinic visit, duplicate blood samples were tested by subjects (N = 147; aged 5-24 yr) and health care providers (HCPs) to evaluate the accuracy and precision of the Didget® system. Subjects' meter results were compared against Yellow Springs Instruments (YSI) reference results and HCP results using least squares regression and error grid analyses. Precision was measured by average within-subject and within-HCP coefficient of variation (CV). During the home-use component of this study, subjects (n = 58) tested their blood glucose at least two to three times daily for 3-5 d to evaluate routine use of the system. Subjects' meter results showed significant correlations with both YSI (r(2) = 0.94; p < 0.001 for regression slope) and HCP results (r(2) = 0.96; p < 0.001). Average within-subject and within-HCP CVs were 5.9 and 7.2%, respectively. Overall satisfaction was assessed by subjects, their parents or guardians, and HCP surveys. Subject satisfaction with the Didget® system was good to excellent; most subjects found the system easy to use, motivating, and helpful for building good blood glucose monitoring habits. Most HCPs agreed that the system fulfilled a need in diabetes management. In conclusion, the Didget® system was precise and clinically accurate in the hands of children, adolescents, and young adults with type 1 diabetes.

Patients with rare and complex diseases such as congenital adrenal hyperplasia (CAH) often receive fragmented and inadequate care unless efforts are coordinated among providers. Translating the concepts of the medical home and comprehensive health care for individuals with CAH offers many benefits for the affected individuals and their families. This manuscript represents the recommendations of a 1.5 day meeting held in September 2009 to discuss the ideal goals for comprehensive care centers for newborns, infants, children, adolescents, and adults with CAH. Participants included pediatric endocrinologists, internal medicine and reproductive endocrinologists, pediatric urologists, pediatric surgeons, psychologists, and pediatric endocrine nurse educators. One unique aspect of this meeting was the active participation of individuals personally affected by CAH as patients or parents of patients. Representatives of Health Research and Services Administration (HRSA), New York-Mid-Atlantic Consortium for Genetics and Newborn Screening Services (NYMAC), and National Newborn Screening and Genetics Resource Center (NNSGRC) also participated. Thus, this document should serve as a “roadmap” for the development phases of comprehensive care centers (CCC) for individuals and families affected by CAH.

Context:Autosomal-recessive mutations in the growth hormone receptor (GHR) are the most common causes for primary growth hormone insensitivity (GHI) syndrome with classical GHI phenotypically characterized by severe short stature and marked insulin-like growth factor (IGF)-I deficiency. We report three families with dominant-negative heterozygous mutations in the intracellular domain of the GHR causing a nonclassical GHI phenotype.Objective:To determine if the identified GHR heterozygous variants exert potential dominant-negative effects and are the cause for the GHI phenotype in our patients.Results:All three mutations (c.964dupG, c.920_921insTCTCAAAGATTACA, and c.945+2T>C) are predicted to result in frameshift and early protein termination. In vitro functional analysis of variants c.964dupG and c.920_921insTCTCAAAGATTACA (c.920_921ins14) suggests that these variants are expressed as truncated proteins and, when coexpressed with wild-type GHR, mimicking the heterozygous state in our patients, exert dominant-negative effects. Additionally, we provide evidence that a combination therapy of recombinant human growth hormone (rhGH) and rhIGF-I improved linear growth to within normal range for one of our previously reported patients with a characterized, dominant-negative GHR (c.899dupC) mutation.Conclusion:Dominant-negative GHR mutations are causal of the mild GHI with substantial growth failure observed in our patients. Heterozygous defects in the intracellular domain of GHR should, therefore, be considered in cases of idiopathic short stature and IGF-I deficiency. Combination therapy of rhGH and rhIGF-I improved growth in one of our patients.

The p.R229H variant, contrary to an earlier report, appeared to function like wild-type GHR and, therefore, is unlikely to cause GHI. The c.899dupC variant is a novel dominant negative mutation that disrupted normal GHR signaling and is the cause for the GHI phenotype of the reported patient.