PIK3R1 mutations cause syndromic insulin resistance with lipoatrophy.

Short stature, hyperextensibility of joints and/or inguinal hernia, ocular depression, Rieger anomaly, and teething delay (SHORT) syndrome is a developmental disorder with an unknown genetic cause and hallmarks that include insulin resistance and lack of subcutaneous fat. We ascertained two unrelated individuals with SHORT syndrome, hypothesized that the observed phenotype was most likely due to de novo mutations in the same gene, and performed whole-exome sequencing in the two probands and their unaffected parents. We then confirmed our initial observations in four other subjects with SHORT syndrome from three families, as well as 14 unrelated subjects presenting with syndromic insulin resistance and/or generalized lipoatrophy associated with dysmorphic features and growth retardation. Overall, we identified in nine affected individuals from eight families de novo or inherited PIK3R1 mutations, including a mutational hotspot (c.1945C>T [p.Arg649Trp]) present in four families. PIK3R1 encodes the p85α, p55α, and p50α regulatory subunits of class IA phosphatidylinositol 3 kinases (PI3Ks), which are known to play a key role in insulin signaling. Functional data from fibroblasts derived from individuals with PIK3R1 mutations showed severe insulin resistance for both proximal and distal PI3K-dependent signaling. Our findings extend the genetic causes of severe insulin-resistance syndromes and provide important information with respect to the function of PIK3R1 in normal development and its role in human diseases, including growth delay, Rieger anomaly and other ocular affections, insulin resistance, diabetes, paucity of fat, and ovarian cysts.

Association of environmental markers with childhood type 1 diabetes mellitus revealed by a long questionnaire on early life exposures and lifestyle in a case-control study.

BACKGROUND: The incidence of childhood type 1 diabetes (T1D) incidence is rising in many countries, supposedly because of changing environmental factors, which are yet largely unknown. The purpose of the study was to unravel environmental markers associated with T1D. METHODS: Cases were children with T1D from the French Isis-Diab cohort. Controls were schoolmates or friends of the patients. Parents were asked to fill a 845-item questionnaire investigating the child's environment before diagnosis. The analysis took into account the matching between cases and controls. A second analysis used propensity score methods. RESULTS: We found a negative association of several lifestyle variables, gastroenteritis episodes, dental hygiene, hazelnut cocoa spread consumption, wasp and bee stings with T1D, consumption of vegetables from a farm and death of a pet by old age. CONCLUSIONS: The found statistical association of new environmental markers with T1D calls for replication in other cohorts and investigation of new environmental areas. TRIAL REGISTRATION: Clinical-Trial.gov NCT02212522 . Registered August 6, 2014.

Pancreatic enzyme replacement therapy for young cystic fibrosis patients.

UNLABELLED: Maldigestion in cystic fibrosis (CF) affects approximately 90% of patients. As soon as pancreatic insufficiency is identified, enzyme supplementation is prescribed even with breast fed infants. A pancreatic enzyme preparation developed particularly for infants, Creon for children (CfC), contains smaller granules to be administered with a dosing spoon (5000 lipase units per scoop). PATIENTS AND METHODS: In a prospective, randomised, multi-centre study, 40 infants and toddlers received both CfC and Creon 10000 (C10) for two weeks each in a cross-over design. Dosing of pancreatic enzymes was continued as applied before the study. The primary endpoint was the parents' treatment preference. Secondary endpoints included coefficient of fat absorption (CFA), clinical symptoms and safety parameters. RESULTS: 20 parents (51%) from the N=39 intent to treat sample preferred CfC, 9 (23%) preferred C10, and 10 (26%) had no preference The applied doses led to a mean CFA with similar results for both treatments (77.8% vs. 78.7%). Gastrointestinal symptoms were reported on a number of study days, and some children had abnormal results for laboratory parameters of malabsorption. Safety and tolerability of the preparations were good and all these parameters were comparable for both treatments. CONCLUSION: Those parents who had a preference favoured CfC over C10. Both enzyme preparations improved malabsorption to a similar degree, although the applied dosages could have been too low in some children reflected in a suboptimal CFA. These data support the use of CfC for young patients with cystic fibrosis improving the daily care of this cohort detected mainly now through neonatal screening programmes.

Gouty tendinitis revealing glycogen storage disease Type Ia in two adolescents.

Hyperuricemia is a well-known consequence of glucose-6-phosphatase (G6Pase) deficiency, the enzymatic abnormality that characterizes glycogen storage disease (GSD) Type Ia. However, acute gout as the presenting manifestation of GSD Type Ia has been reported in only a few patients. We report a new case in a 17-year-old male evaluated for acute gouty tendinitis in the right Achilles tendon. Blood tests showed chronic acidosis with high levels of uric acid, lactic acid, and cholesterol. A liver enzyme study confirmed the diagnosis of GSD Type Ia. A genetic study showed that the index patient and his sister were composite heterozygotes for the known mutation R83C and the previously unreported mutation M5R. Acute gout in an adolescent with liver enlargement and high blood levels of uric acid and cholesterol should suggest GSD. Demonstration by molecular biology techniques of a mutation in both alleles of the G6Pase gene establishes the diagnosis of GSD Type Ia, obviating the need for a liver biopsy.