Long-term weight gain in children with craniopharyngioma

OBJECTIVE

Adamantinomatous craniopharyngioma mainly affects children. Excessive weight gain is a major long-term complication. The primary objective of this study was to assess long-term weight changes in children treated for craniopharyngioma. The secondary objectives were to identify risk factors for excessive weight gain and to look for associations with hypothalamic damage by the tumour or treatment.

DESIGN

Single-centre retrospective cohort study.

METHOD

Children managed for craniopharyngioma at our centre between 1990 and 2019 were included. The body mass index (BMI) standard deviation scores (SDS) at baseline and at last follow-up were compared. Univariate and multivariate analyses were performed in order to identify variables associated with the long-term BMI-SDS variation.

RESULTS

The 108 patients had a mean follow-up of 10.4 years. The mean BMI-SDS increase over time was 2.11 (P < .001) overall, 1.21 (P < .001) in the group without hypothalamic involvement by the tumour, and 1.95 (P < .001) in the group managed using intended hypothalamus-sparing surgery. The absence of hypothalamic involvement by the tumour or treatment was significantly associated with less weight gain (P = .046 and P < .01, respectively). After adjustment, factors associated with a BMI-SDS change greater than 2 were female sex (P = .023), tumour involving the hypothalamus (P = .04), and higher baseline BMI (P < .001).

CONCLUSION

Clinically significant weight gain occurred in nearly all children treated for craniopharyngioma, including those whose hypothalamus was spared by the tumour and intentionally by treatment. However, hypothalamus integrity was associated with less weight gain. Despite hypothalamus-sparing strategies, hypothalamic obesity remains a major concern, indicating a need for novel treatment approaches.

Very long-term outcomes of pediatric patients treated for optic pathway gliomas: A longitudinal cohort study

BACKGROUND

Optic pathway gliomas (OPG) represent 5% of childhood brain tumors. Successive relapses lead to multiple treatments exposing to late complications.

METHODS

We included patients treated at Gustave Roussy (GR) between 01.1980 and 12.2015 for OPG, before 18 years-old and alive at 5 years from diagnosis. Mortality and physical health conditions data were extracted from medical data files and updated thanks to the GR long-term follow-up program and French national mortality registry for patients included in the French Childhood Cancer Survivor Study.

RESULTS

We included 182 5y-OPG-childhood survivors in the analysis (sex-ratio M/F 0.8, 35% with NF1). With a median follow-up of 17.2y (range=5-41), we registered 82 relapses, 9 second malignancies and 15 deaths as first events after 5 years, resulting in 20-y conditional overall survival (C-OS) and late events-free survival (LEFS) of 79.9% (95%CI=71-86) and 43.5% (95%CI=36-51) respectively. NF1 (Hazard ratio HR=3, 95%CI=1.4-6.8), hypothalamic involvement (HR=3.2, 95%CI=1.4-7.3), and radiotherapy (HR=2.8, 95%CI=1.1-6.7) were significantly associated with C-OS in multivariable analyses. Ninety-five percent of 5y-OPG survivors suffered from any health condition, especially visual acuity "<1/10" (n=109), pituitary deficiency (n=106) and neurocognitive impairment (n=89). NF1 (HR 2.1) was associated with precocious puberty. With a median time post diagnosis of 4.2 years, 33 cerebrovascular events were observed in 21 patients.

CONCLUSION

Late relapses, second malignancies and cerebrovascular diseases are severe late events resulting in premature mortality. Morbidity is high and needing after-cancer care to improve quality of life. Risk factors could be considered to better stratify long-term follow-up.

Efficacy of a Hybrid Closed-Loop Solution in Patients With Excessive Time in Hypoglycaemia: A Post Hoc Analysis of Trials With DBLG1 System

BACKGROUND

Automated insulin delivery is an efficient treatment for patients with type 1 diabetes. Little is known on its impact on patients with excessive time in hypoglycaemia.

METHODS

We performed a post hoc analysis of three randomized control trials that used the DBLG1 (Diabeloop Generation 1) hybrid closed-loop solution. Patients whose time below 70 mg/dL during baseline, open-loop phase exceeded 5% were selected. The outcomes were the differences between the closed-loop and the open-loop phases in time in various ranges and Glycemia Risk Index (GRI).

RESULTS

We identified 45 patients exhibiting ≥5% of time below 70 mg/dL during the open-loop phase. Under closed-loop, the time in hypoglycaemia (54 to <70 mg/dL) dropped from 7.9% (SD 2.4) to 3.2% (SD 1.6) (difference -4.7% [-5.3; -4.1], P < 10-4). The time below 54 mg/dL decreased from 1.9% (SD 1.3) to 0.8% (SD 0.7) (difference -0.9% [-1.4; -0.8], P < 10-4). The time in range (TIR 70-180 mg/dL) improved from 63.3 (SD 9.5) to 68.2% (SD 8.2) (difference 5.1% [2.9; 7.0], P < 10-4). The GRI improved from 51.2 (SD 12.4) to 38.0 (SD 10.9) (difference 13.2 [10.4; 16.0], P < 10-4).

CONCLUSION

DBLG1 decreased time in hypoglycaemia by more than 50% even in patients with excessive time in hypoglycaemia at baseline, while also improving both TIR and GRI, under real-life conditions. The improvement in GRI (13.2%) exceeded that of the improvement in TIR (5.1%) indicating that in this data set, GRI was more sensitive than TIR to the improvement in glycaemia achieved with closed-loop. These results support the safety and efficacy of this treatment.

Glucose pattern in children with classical congenital adrenal hyperplasia: evidence from continuous glucose monitoring

BACKGROUND

While the risk for hypoglycemia during acute illness is well described in children with classical congenital adrenal hyperplasia (CAH), there is little evidence for the prevalence of asymptomatic hypoglycemia and the daily glucose patterns in CAH. Herein, we explored the daytime glucose profile of children with classical CAH.

METHODS

We conducted an observational study in 11 children (6 female; age 3.1 years [1.4, 5.1]; body mass index 17.3 kg/m2 [15.6, 17.9]) with a genetic diagnosis of classical CAH receiving hydrocortisone and fludrocortisone replacement therapy. Participants underwent 2 14-day continuous glucose monitoring (CGM) sessions and an inpatient 24 h series cortisol and adrenocorticotropic hormone (ACTH) measures. Data were analyzed for 3 daytime lags (7 Am-4 Pm, 4 Pm-10pm, 10 Pm-7 Am) corresponding to the hydrocortisone dosing period with cortisol and ACTH measured before the hydrocortisone dose.

RESULTS

Eleven participants completed at least 1 CGM session, and 7 out of 11 underwent both the CGM session and the cortisol/ACTH serial measures. In the whole cohort, the percentage of time of sensor glucose values <70 mg/dL was higher during the 10 Pm-7 Am and the 7 Am-4 Pm time slots than in the late afternoon period (17% [7, 54] and 15% [6.8, 24] vs 2% [1.1, 16.7] during the periods 7 Am-4 Pm and 4 Pm-10 Pm, respectively [P = .006 and P = .003]). Nighttime hypoglycemia was mostly spent below the 65 mg/dL (10.9% [4.1, 34]). The glycemic pattern paralleled the nadir of daily cortisol at 7 Am (10.3±4.4 μg/dL). A greater percentage of time in hypoglycemia was associated with lower cortisol concentration at 7 Am and 10 Pm (P < .001 and P = .005).

CONCLUSIONS

Continuous glucose monitoring demonstrated a disrupted daily glucose pattern in children with CAH, paralleled by a lower cortisol concentration.

CLINICALTRIALS.GOV REGISTRATION

NCT04322435.

First Generation of a Modular Interoperable Closed-Loop System for Automated Insulin Delivery in Patients With Type 1 Diabetes: Lessons From Trials and Real-Life Data

BACKGROUND

DBLG1 (Diabeloop Generation 1) stands as one of the five commercially available closed-loop solution worldwide for patients with type 1 diabetes as of 2023. Our aim was to provide an overview of all data obtained with this system regarding outcomes and populations, with an emphasis on interoperability.

METHODS

This report includes all available sources of data (three randomized control trials and five surveys on real-life data). Collection ran from March 3, 2017 to April 30, 2022.

RESULTS

We gathered data from 6859 adult patients treated with closed-loop from three to 12 months. Overall, all sources of data showed that time in range (TIR) 70 to 180 mg/dL, starting from 47.4% to 56.6%, improved from 12.2 to 17.3 percentage points. Time in hypoglycemia was reduced by 48% in average (range: 26%-70%) and reached a level of 1.3% in the largest and most recent cohort. In patients with excessive time in hypoglycemia at baseline (≥5%), closed-loop allowed a reduction in time below range (TBR) by 59%. The comparison of days with declared physical activity versus days without physical activity did not show differences in TBR. The improvement in TIR observed with three different pump systems (Vicentra Kaleido, n = 117; Sooil Dana-I, n = 84; and Roche Insight, n = 6684) ranged from 15.4 to 17.3 percentage points.

DISCUSSION

These data obtained in different European countries were consistent throughout all reports, showing that this closed-loop system is efficient (high improvement in TIR), safe (remarkably low level of TBR), and interoperable (three pump settings so far).

Borealin/CDCA8 deficiency alters thyroid development and results in papillary tumor-like structures

Background

BOREALIN/CDCA8 mutations are associated with congenital hypothyroidism and thyroid dysgenesis. Borealin is involved in mitosis as part of the Chromosomal Passenger Complex. Although BOREALIN mutations decrease thyrocyte adhesion and migration, little is known about the specific role of Borealin in the thyroid.

Methods

We characterized thyroid development and function in Borealin-deficient (Borealin +/-) mice using histology, transcriptomic analysis, and quantitative PCR.

Results

Thyroid development was impaired with a hyperplastic anlage on embryonic day E9.5 followed by thyroid hypoplasia from E11.5 onward. Adult Borealin +/- mice exhibited euthyroid goiter and defect in thyroid hormone synthesis. Borealin +/- aged mice had disorganized follicles and papillary-like structures in thyroids due to ERK pathway activation and a strong increase of Braf-like genes described by The Cancer Genome Atlas (TCGA) network of papillary thyroid carcinoma. Moreover, Borealin +/- thyroids exhibited structural and transcriptomic similarities with papillary thyroid carcinoma tissue from a human patient harboring a BOREALIN mutation, suggesting a role in thyroid tumor susceptibility.

Conclusion

These findings demonstrate Borealin involvement in critical steps of thyroid structural development and function throughout life. They support a role for Borealin in thyroid dysgenesis with congenital hypothyroidism. Close monitoring for thyroid cancer seems warranted in patients carrying BOREALIN mutations.

Identifying patient-related predictors of permanent growth hormone deficiency

Objective

Isolated childhood growth hormone deficiency (GHD) can persist into adulthood, and re-testing at the transition period is needed to determine whether continued growth hormone therapy is indicated. Here, our objective was to identify predictors of permanent GHD.

Design

Retrospective single-centre study of patients with childhood-onset GHD who were re-tested after adult height attainment.

Methods

Auxological, clinical, laboratory, and MRI data throughout follow-up were collected.

Results

We included 101 patients. At GH treatment initiation, age was 8.1 ± 0.4 years, height -2.25 ± 0.8, and BMI -0.27 ± 0.1 SDS. The 29 (28.7%) patients with persistent GHD had lower height SDS (-2.57 ± 0.1 vs. -2.11 ± 0.1, p<0.001) and mean GH peaks (8.4 ± 1.0 vs.13.2 ± 0.5 mIU/L, p<0.001) at GHD diagnosis; at adult height, they had lower IGF1 (232 ± 19.9 vs. 331 ± 9.1 ng/mL, p<0.001) and higher BMI SDS (-0.15 ± 0.27 vs. -0.73 ± 0.13, p<0.005). By multivariate analysis, the best predictive model included height and BMI SDS, both GH peaks, and MRI findings at diagnosis. Patients with height at diagnosis <-3 SDS had a 7.7 (95% IC 1.4-43.1, p=0.02) fold higher risk of persistent GHD after adjustment on BMI SDS. An abnormal pituitary region by MRI was the strongest single predictor (7.2 times, 95% CI 2.7-19.8) and after multivariate analysis adjustment for GH peaks and height SDS at diagnosis, the risk increased to 10.6 (1.8 - 61.3) times.

Conclusions

Height <-3 SDS at GHD diagnosis and pituitary MRI abnormalities should lead to a high index of suspicion for persistent GHD.

Assessment of Puberty and Hypothalamic-Pituitary-Gonadal Axis Function After Childhood Brain Tumor Treatment

CONTEXT

Endocrine complications are common in pediatric brain tumor patients.

OBJECTIVE

To describe hypothalamic-pituitary-gonadal axis (HPGA) function in patients treated in childhood for a primary brain tumor more than 5 years earlier, in order to identify risk factors for HPGA impairment.

METHODS

We retrospectively included 204 patients diagnosed with a primary brain tumor before 18 years of age and monitored at the pediatric endocrinology unit of the Necker Enfants-Malades University Hospital (Paris, France) between January 2010 and December 2015. Patients with pituitary adenoma or untreated glioma were excluded.

RESULTS

Among patients with suprasellar glioma not treated by radiotherapy, the prevalence of advanced puberty was 65% overall and 70% when the diagnosis occurred before 5 years of age. Medulloblastoma chemotherapy caused gonadal toxicity in 70% of all patients and in 87.5% of those younger than 5 years at diagnosis. In the group with craniopharyngioma, 70% of patients had hypogonadotropic hypogonadism, which was consistently accompanied by growth hormone deficiency.

CONCLUSION

Tumor type, location, and treatment were the risk main factors for HPGA impairment. Awareness that onset can be delayed is essential to guide information of parents and patients, patient monitoring, and timely hormone replacement therapy.

GH and Childhood-onset Craniopharyngioma: When to Initiate GH Replacement Therapy?

CONTEXT

Craniopharyngioma is a benign brain tumor with frequent local recurrence or progression after treatment. GH replacement therapy (GHRT) is prescribed in children with GH deficiency resulting from childhood-onset craniopharyngioma.

OBJECTIVE

To evaluate whether a shorter delay of GHRT initiation after childhood-onset craniopharyngioma completion therapy increased the risk of a new event (progression or recurrence).

METHODS

Retrospective, observational, monocenter study. We compared a cohort of 71 childhood-onset patients with craniopharyngiomas treated with recombinant human GH (rhGH). Twenty-seven patients were treated with rhGH at least 12 months after craniopharyngioma treatment (>12-month group) and 44 patients before 12 months (<12-month group), among which 29 patients were treated between 6 and 12 months (6-12 month group). The main outcome was the risk of tumor new event (progression of residual tumor or tumor recurrence after complete resection) after primary treatment in the >12-month group and in the <12 month or in the 6- to 12-month group patients.

RESULTS

In the >12-month group, the 2- and 5-year event-free survivals were respectively 81.5% (95% CI, 61.1-91.9) and 69.4% (95% CI, 47.9-83.4) compared with 72.2% (95% CI, 56.3-83.1) and 69.8% (95% CI, 53.8-81.2) in the <12-month group. The 2- and 5-year event-free survivals were the same in the 6- to 12-month group (72.4%; 95% CI, 52.4-85.1). By log-rank test, the event-free survival was not different between groups (P = .98 and P = .91).The median time for event was not statistically different.In univariate and multivariate analysis, the risk of craniopharyngioma new event was not associated with the GHRT time delay after craniopharyngioma treatment.

CONCLUSIONS

No association was found between GHRT time delay after childhood-onset craniopharyngioma treatment and an increased risk of recurrence or tumor progression, suggesting GH replacement therapy can be initiated 6 months after last treatment for craniopharyngiomas.

Approach to the Patient With Congenital Hypothyroidism

Congenital hypothyroidism (CH) is the most frequent neonatal endocrine disorder and the most common preventable cause of development delay and growth failure if diagnosed and treated early. The thyroid is the first endocrine gland to develop during embryonic life and to be recognizable in humans. Thyroid development and maturation can be divided into 2 phases: a first phase of embryogenesis and a second phase of folliculogenesis and differentiation with thyroid hormone production at the final steps. Regulation of the thyroid function requires normal development of the hypothalamic-pituitary-thyroid axis, which occurs during the embryonic and neonatal period. Defects in any of steps of thyroid development, differentiation, and regulation lead to permanent CH. Newborn screening programs, established in only one-third of countries worldwide, detect CH and are cost-effective and highly sensitive and specific. During the last decade, epidemiology of CH has changed with increased frequency of thyroid in situ in primary CH. Advances in molecular testing have expanded knowledge and understanding of thyroid development and function. However, a molecular cause is identified in only 5% of CH due to thyroid dysgenesis. The purpose of this article is to describe the clinical approach to the child with CH, focusing on diagnostic work-up and future challenges on optimizing thyroid replacement therapy and regenerative medicine. The review is written from the perspective of the case of 2 girls referred for CH after newborn screening and diagnosed with thyroid ectopy. The genetic work-up revealed novel mutations in TUBB1 gene, associated with large platelets and abnormal platelet physiology.

Sulfonylurea for improving neurological features in neonatal diabetes: A systematic review and meta-analyses

OBJECTIVE

In monogenic diabetes due to KCNJ11 and ABCC8 mutations that impair KATP- channel function, sulfonylureas improve long-term glycemic control. Although KATP channels are extensively expressed in the brain, the effect of sulfonylureas on neurological function has varied widely. We evaluated published evidence about potential effects of sulfonylureas on neurological features, especially epilepsy, cognition, motor function and muscular tone, visuo-motor integration, and attention deficits in children and adults with KCNJ11 and ABCC8-related neonatal-onset diabetes mellitus.

RESEARCH DESIGN AND METHODS

We conducted a systematic review and meta-analyses of the literature (PROSPERO, CRD42021254782), including individual-patient data, according to PRISMA, using RevMan software. We also graded the level of evidence.

RESULTS

We selected 34 of 776 publications. The evaluation of global neurological function before and after sulfonylurea (glibenclamide) treatment in 114 patients yielded a risk difference (RD) of 58% (95%CI, 43%-74%; I²  = 54%) overall and 73% (95%CI, 32%-113%; I²  = 0%) in the subgroup younger than 4 years; the level of evidence was moderate and high, respectively. EEG studies of epilepsy showed a RD of 56% (95%CI, 23%-89%; I²  = 34%) in patients with KCNJ11 mutations, with a high quality of evidence. For hypotonia and motor function, the RDs were 90% (95%CI, 69%-111%; I²  = 0%) and 73% (95%CI, 35%-111%; I²  = 0%), respectively, with a high level of evidence.

CONCLUSIONS

Glibenclamide significantly improved neurological abnormalities in patients with neonatal-onset diabetes due to KCNJ11 or ABCC8 mutations. Hypotonia was the symptom that responded best. Earlier treatment initiation was associated with greater benefits.

Genetics of congenital hypothyroidism: Modern concepts

Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder and one of the most common preventable causes of intellectual disability in the world. CH may be due to developmental or functional thyroid defects (primary or peripheral CH) or be hypothalamic‐pituitary in origin (central CH). In most cases, primary CH is caused by a developmental malformation of the gland (thyroid dysgenesis, TD) or by a defect in thyroid hormones synthesis (dyshormonogenesis, DH). TD represents about 65% of CH and a genetic cause is currently identified in fewer than 5% of patients. The remaining 35% are cases of DH and are explained with certainty at the molecular level in more than 50% of cases. The etiology of CH is mostly unknown and may include contributions from individual and environmental factors. In recent years, the detailed phenotypic description of patients, high‐throughput sequencing technologies, and the use of animal models have made it possible to discover new genes involved in the development or function of the thyroid gland. This paper reviews all the genetic causes of CH. The modes by which CH is transmitted will also be discussed, including a new oligogenic model. CH is no longer simply a dominant disease for cases of CH due to TD and recessive for cases of CH due to DH, but a far more complex disorder.

High Prevalence of Early Endocrine Disorders After Childhood Brain Tumors in a Large Cohort

CONTEXT

Endocrine complications are common in pediatric brain tumor patients.

OBJECTIVE

We aimed to describe the endocrine follow-up of patients with primary brain tumors.

METHODS

This is a noninterventional observational study based on data collection from medical records of 221 patients followed at a Pediatric Endocrinology Department.

RESULTS

Median age at diagnosis was 6.7 years (range, 0-15.9), median follow-up 6.7 years (0.3-26.6), 48.9% female. Main tumor types were medulloblastoma (37.6%), craniopharyngioma (29.0%), and glioma (20.4%). By anatomic location, 48% were suprasellar (SS) and 52% non-suprasellar (NSS). Growth hormone deficiency (GHD) prevalence was similar in both groups (SS: 83.0%, NSS: 76.5%; P = 0.338), appearing at median 1.8 years (-0.8 to 12.4) after diagnosis; postradiotherapy GHD appeared median 1.6 years after radiotherapy (0.2-10.7). Hypothyroidism was more prevalent in SS (76.4%), than NSS (33.9%) (P < 0.001), as well as ACTH deficiency (SS: 69.8%, NSS: 6.1%; P < 0.001). Early puberty was similar in SS (16%) and NSS (12.2%). Hypogonadotropic hypogonadism was predominant in SS (63.1%) vs NSS (1.3%), P < 0.001, and postchemotherapy gonadal toxicity in NSS (29.6%) vs SS (2.8%), P < 0.001. Adult height was lower for NSS compared to target height (-1.0 SD, P < 0.0001) and to SS patients (P < 0.0001). Thyroid nodules were found in 13/45 patients (28.8%), including 4 cancers (4.8-11.5 years after radiotherapy). Last follow-up visit BMI was higher in both groups (P = 0.0001), and obesity incidence was higher for SS (46.2%) than NSS (17.4%).

CONCLUSION

We found a high incidence of early-onset endocrine disorders. An endocrine consultation and nutritional evaluation should be mandatory for all patients with a brain tumor, especially when the tumor is suprasellar or after hypothalamus/pituitary irradiation.

[Genetic of congenital hypothyroidism]

Congenital hypothyroidism (CH) is the most frequent neonatal endocrine disorder. CH is due to thyroid development or thyroid function defects (primary) or may be of hypothalamic-pituitary origin (central). Primary CH is caused essentially by abnormal thyroid gland morphogenesis (thyroid dysgenesis, TD) or defective thyroid hormone synthesis (dyshormonogenesis, DH). DH accounts for about 35% of CH and a genetic cause is identified in 50% of patients. However, TD accounts for about 65% of CH, and a genetic cause is identified in less than 5% of patients. The pathogenesis of CH is largely unknown and may include the contribution of individual and environmental factors. During the last years, detailed phenotypic description of patients, next-generation sequence technologies and use of animal models allowed the discovery of novel candidate genes in thyroid development and function. We provide an overview of recent genetic causes of primary and central CH. In addition, mode of inheritance and the oligogenic model of CH are discussed.

Neonatal Screening for Hyperthyroidism Proof of Concept

CONTEXT

Early treatment is essential to avoid the cardiac complication of neonatal hyperthyroidism (NH). Our results have direct implications for clinical care.

OBJECTIVE

NH can cause potentially fatal neonatal thyrotoxicosis. Here, we have evaluated the feasibility of neonatal hyperthyroidism screening using the thyroid-stimulating hormone value in dried blood collected routinely on filter paper on the third postnatal day of life for congenital hypothyroidism screening.

METHODS

Retrospective case-control study. Cases were identified using data from our previously published study of 280 000 infants born in 10 maternity units in France in 2007-2014. Controls were identified among the 1 362 564 infants born in the Ile-de-France region during the same period.

RESULTS

A screening thyroid-stimulating hormone level below 0.18 mIU/L on the third postnatal day had 71% (95% CI 44-90%) sensitivity, 99% (95% CI 99-100%) specificity, 81% (95% CI 74-86%) positive predictive value, and 98% (95% CI 97-99%) negative predictive value for detecting severe NH. By univariate regression analysis, the screening thyroid-stimulating hormone value was the strongest predictor of NH (P < .00001), with an area under the receiver-operating characteristics curve of 0.98 (95% CI 0.95-1.0). Expected frequencies were not significantly different from observed frequencies (Hosmer-Lemeshow test, P = .99).

CONCLUSION

The screening thyroid-stimulating hormone test can be used to detect severe NH, the optimal cut-off being 0.18 mIU/L. The additional cost compared with screening for congenital hypothyroidism would be small. Infants with neonatal hyperthyroidism would benefit from an earlier diagnosis with treatment initiation at the presymptomatic stage in many cases, ensuring optimal outcomes.

Mitchell-Riley Syndrome: Improving Clinical Outcomes and Searching for Functional Impact of RFX-6 Mutations

AIMS/HYPOTHESIS

Caused by biallelic mutations of the gene encoding the transcription factor RFX6, the rare Mitchell-Riley syndrome (MRS) comprises neonatal diabetes, pancreatic hypoplasia, gallbladder agenesis or hypoplasia, duodenal atresia, and severe chronic diarrhea. So far, sixteen cases have been reported, all with a poor prognosis. This study discusses the multidisciplinary intensive clinical management of 4 new cases of MRS that survived over the first 2 years of life. Moreover, it demonstrates how the mutations impair the RFX6 function.

METHODS

Clinical records were analyzed and described in detail. The functional impact of two RFX6^R181W and RFX6^V506G variants was assessed by measuring their ability to transactivate insulin transcription and genes that encode the L-type calcium channels required for normal pancreatic beta-cell function.

RESULTS

All four patients were small for gestational age (SGA) and prenatally diagnosed with duodenal atresia. They presented with neonatal diabetes early in life and were treated with intravenous insulin therapy before switching to subcutaneous insulin pump therapy. All patients faced recurrent hypoglycemic episodes, exacerbated when parenteral nutrition (PN) was disconnected. A sensor-augmented insulin pump therapy with a predictive low-glucose suspension system was installed with good results. One patient had a homozygous c.1517T>G (p.Val506Gly) mutation, two patients had a homozygous p.Arg181Trp mutation, and one patient presented with new compound heterozygosity. The RFX6^V506G and RFX6^R181W mutations failed to transactivate the expression of insulin and genes that encode L-type calcium channel subunits required for normal pancreatic beta-cell function.

CONCLUSIONS/INTERPRETATION

Multidisciplinary and intensive disease management improved the clinical outcomes in four patients with MRS, including adjustment of parenteral/oral nutrition progression and advanced diabetes technologies. A better understanding of RFX6 function, in both intestine and pancreas cells, may break ground in new therapies, particularly regarding the use of drugs that modulate the enteroendocrine system.

Clinical and molecular analysis of smoothened inhibitors in Sonic Hedgehog medulloblastoma

Background

Smoothened inhibitors (SMOi) have shown activity in Sonic Hedgehog (SHH) medulloblastoma, however this therapeutic class was not developed in children due to severe effects reported on growth. We hereby report long-term follow-up of young patients treated with SMOi for recurrent medulloblastoma.

Methods

Clinical data on response and toxicity from patients treated with vismodegib or sonidegib from 2011 to 2019 for a SHH medulloblastoma were retrospectively reviewed. Methylation analysis and whole exome sequencing were performed whenever possible.

Results

All patients with a somatic PTCH1 mutation responded to SMOi (6/8), including 2 prolonged complete responses. One patient was free of disease 8.2 years after treatment. SMOi was challenged again for 3 patients. Two of them had a response, one with SMOi alone, the other one in combination with temozolomide despite previous progression under monotherapy. SMO resistance mutations were found in patients from biopsy at relapse. Combination with temozolomide or surgery plus radiotherapy was associated with very long disease control in 2 patients. The most severe adverse events were myalgia and growth plate fusion with metaphyseal sclerosis. Normal growth velocity was recovered for 1 patient although her final height was below estimated target height.

Conclusions

Targeting SMO in mutated PTCH1 is an interesting strategy for long-term responses. Combination of SMOi with chemotherapy or surgery and local radiotherapy is an appealing strategy to prevent early resistance and diminish SMOi exposure, especially in young patients. Inhibition of SHH pathway causes growth and development impairment but partial recovery of the growth velocity is possible.

[Newborn screening for congenital adrenal hyperplasia in France]

Congenital Adrenal Hyperplasia (CAH) is a genetic disorder, mostly (95%) due to CYP21A2 mutations. Its incidence in France is 1/15,000 to 1/16,000 births. The screening of newborns in France is effective since 1996, by using a 17-hydroxyprogesterone dosage on a dried blood spot. This screening allowed, as in other countries, a decrease in mortality and in morbidity by earlier management of adrenal crisis usually symptomatic from the 2^nd week after birth. The French Newborn Screening has for now adopted the two-tier screens on the same dried blood spot, using a fluoroimmunoassay on both screens. This approach provides a high sensitivity, but has also a low positive predictive value. New strategies including the LC-MS/MS method can be considered in the future.

Lopinavir-Ritonavir Impairs Adrenal Function in Infants

BACKGROUND

Perinatal treatment with lopinavir boosted by ritonavir (LPV/r) is associated with steroidogenic abnormalities. Long-term effects in infants have not been studied.

METHODS

Adrenal-hormone profiles were compared at weeks 6 and 26 between human immunodeficiency virus (HIV)-1-exposed but uninfected infants randomly assigned at 7 days of life to prophylaxis with LPV/r or lamivudine (3TC) to prevent transmission during breastfeeding. LPV/r in vitro effect on steroidogenesis was assessed in H295R cells.

RESULTS

At week 6, 159 frozen plasma samples from Burkina Faso and South Africa were assessed (LPV/r group: n = 92; 3TC group: n = 67) and at week 26, 95 samples from Burkina Faso (LPV/r group: n = 47; 3TC group: n = 48). At week 6, LPV/r-treated infants had a higher median dehydroepiandrosterone (DHEA) level than infants from the 3TC arm: 3.91 versus 1.48 ng/mL (P < .001). Higher DHEA levels (>5 ng/mL) at week 6 were associated with higher 17-OH-pregnenolone (7.78 vs 3.71 ng/mL, P = .0004) and lower testosterone (0.05 vs 1.34 ng/mL, P = .009) levels in LPV/r-exposed children. There was a significant correlation between the DHEA and LPV/r AUC levels (ρ = 0.40, P = .019) and Ctrough (ρ = 0.40, P = .017). At week 26, DHEA levels remained higher in the LPV/r arm: 0.45 versus 0.13 ng/mL (P = .002). Lopinavir, but not ritonavir, inhibited CYP17A1 and CYP21A2 activity in H295R cells.

CONCLUSIONS

Lopinavir was associated with dose-dependent adrenal dysfunction in infants. The impact of long-term exposure and potential clinical consequences require evaluation.

CLINICAL TRIALS REGISTRATION

NCT00640263.

Prior infection by seasonal coronaviruses, as assessed by serology, does not prevent SARS-CoV-2 infection and disease in children, France, April to June 2020

BackgroundChildren have a low rate of COVID-19 and secondary severe multisystem inflammatory syndrome (MIS) but present a high prevalence of symptomatic seasonal coronavirus infections.AimWe tested if prior infections by seasonal coronaviruses (HCoV) NL63, HKU1, 229E or OC43 as assessed by serology, provide cross-protective immunity against SARS-CoV-2 infection.MethodsWe set a cross-sectional observational multicentric study in pauci- or asymptomatic children hospitalised in Paris during the first wave for reasons other than COVID (hospitalised children (HOS), n = 739) plus children presenting with MIS (n = 36). SARS-CoV-2 antibodies directed against the nucleoprotein (N) and S1 and S2 domains of the spike (S) proteins were monitored by an in-house luciferase immunoprecipitation system assay. We randomly selected 69 SARS-CoV-2-seropositive patients (including 15 with MIS) and 115 matched SARS-CoV-2-seronegative patients (controls (CTL)). We measured antibodies against SARS-CoV-2 and HCoV as evidence for prior corresponding infections and assessed if SARS-CoV-2 prevalence of infection and levels of antibody responses were shaped by prior seasonal coronavirus infections.ResultsPrevalence of HCoV infections were similar in HOS, MIS and CTL groups. Antibody levels against HCoV were not significantly different in the three groups and were not related to the level of SARS-CoV-2 antibodies in the HOS and MIS groups. SARS-CoV-2 antibody profiles were different between HOS and MIS children.ConclusionPrior infection by seasonal coronaviruses, as assessed by serology, does not interfere with SARS-CoV-2 infection and related MIS in children.

New genetics in congenital hypothyroidism

INTRODUCTION

Congenital hypothyroidism (CH) is the most frequent neonatal endocrine disorder and one of the most common preventable forms of mental retardation worldwide. CH is due to thyroid development or thyroid function defects (primary) or may be of hypothalamic-pituitary origin (central). Primary CH is caused essentially by abnormal thyroid gland morphogenesis (thyroid dysgenesis, TD) or defective thyroid hormone synthesis (dyshormonogenesis, DH). TD accounts for about 65% of CH, however a genetic cause is identified in less than 5% of patients.

PURPOSE

The pathogenesis of CH is largely unknown and may include the contribution of individual and environmental factors. During the last years, detailed phenotypic description of patients, next-generation sequence technologies and use of animal models allowed the discovery of novel candidate genes in thyroid development, function and pathways.

RESULTS AND CONCLUSION

We provide an overview of recent genetic causes of primary and central CH. In addition, mode of inheritance and the oligogenic model of CH are discussed.

Puberty and fertility in classic galactosemia

Classic galactosemia is a rare inborn error of galactose metabolism with a birth prevalence of about 1/30,000-60,000. Long-term complications occurring despite dietary treatment consist of premature ovarian insufficiency (POI) and neurodevelopmental impairments. We performed with the French Reference Centers for Rare Diseases a multisite collaborative questionnaire survey for classic galactosemic patients. Its primary objective was to assess their puberty, pregnancy, gonadotropic axis, and pelvic morphology by ultrasound. The secondary objective was to determine predictive factors for pregnancy without oocyte donation. Completed questionnaires from 103 patients, 56 females (median age, 19 years (3-52 years)) and 47 males (median age, 19 years (3-45 years)), were analyzed. Among the 43 females older than 13 years old, mean age for breast development first stage was 13.8 years; spontaneous menarche occurred in 21/31 females at a mean age of 14.6 years. In these 21 women, 62% had spaniomenorrhea and 7/17 older than 30 years had amenorrhea. All age-groups confounded, FSH was above reference range for 65.7% of the patients, anti-Müllerian hormone and inhibin B were undetectable, and the ovaries were small with few or no follicles detected. Among the 5 females who sought to conceive, 4 had pregnancies. Among the 47 males, 1 had cryptorchidism, all have normal testicular function and none had a desire to conceive children. Thus, spontaneous puberty and POI are both common in this population. Spontaneous menarche seems to be the best predictive factor for successful spontaneous pregnancy.

First case of fetal goitrous hypothyroidism due to SLC5A5/NIS mutations

BACKGROUND

Among patients with congenital hypothyroidism, 35% have dyshormonogenesis (DH) with thyroid gland in situ with or without goiter. The majority of DH cases are due to mutations in genes involved in thyroid hormone production as TG, TPO, SLC5A5/NIS, SLC26A4/PDS, IYD/DEHAL1, DUOX2, and DUOXA2, and are usually inherited on an autosomal recessive basis. Most previously reported cases of fetal hypothyroidism and goiter were related to TG or TPO mutations and recently DUOXA2.

PATIENT

In a male patient with antenatal goiter treated with intraamniotic levothyroxine injections, whose long-term follow-up is described in detail, two novel NIS mutations were detected. Mutations of NIS were located in exon 1 (c.52G>A, p.G18R) and exon 13 (c.1546C>T, p.R516X), each mutation was inherited from parents, who are healthy carriers. The p.G18R mutation affecting the first transmembrane domain of the protein can be responsible for deficient iodide uptake. However, the second is a nonsense mutation leading probably to mRNA degradation. In addition, the patient has undergone a thyroidectomy and we have studied the thyroid tissue. The thyroid histology showed heterogeneity with large follicles, epithelial hyperplasia and many areas of fibrosis. Immunohistochemistry with NIS specific antibody showed NIS staining at the basolateral plasma membrane of the thyrocytes.

CONCLUSIONS

We report the first case of fetal goitrous hypothyroidism due to two novel NIS mutations with access to thyroid tissue of the patient, specific histology studies and long-term follow-up. This case expands our knowledge and provides further insights on molecular causes of fetal goiter in humans.

Wnt/β-catenin activation cooperates with loss of p53 to cause adrenocortical carcinoma in mice

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with limited therapeutic options. The lack of mouse models that recapitulate the genetics of ACC has hampered progress in the field. We analyzed The Cancer Genome Atlas (TCGA) dataset for ACC and found that patients harboring alterations in both p53/Rb and Wnt/β-catenin signaling pathways show a worse prognosis compared with patients that harbored alterations in only one. To model this, we utilized the Cyp11b2(AS)^Cre mouse line to generate mice with adrenocortical-specific Wnt/β-catenin activation, Trp53 deletion, or the combination of both. Mice with targeted Wnt/β-catenin activation or Trp53 deletion showed no changes associated with tumor formation. In contrast, alterations in both pathways led to ACC with pulmonary metastases. Similar to ACCs in humans, these tumors produced increased levels of corticosterone and aldosterone and showed a high proliferation index. Gene expression analysis revealed that mouse tumors exhibited downregulation of Star and Cyp11b1 and upregulation of Ezh2, similar to ACC patients with a poor prognosis. Altogether, these data show that altering both Wnt/β-catenin and p53/Rb signaling is sufficient to drive ACC in mouse. This autochthonous model of ACC represents a new tool to investigate the biology of ACC and to identify new treatment strategies.

High Diagnostic Yield of Targeted Next-Generation Sequencing in a Cohort of Patients With Congenital Hypothyroidism Due to Dyshormonogenesis

OBJECTIVE

To elucidate the molecular cause in a well-characterized cohort of patients with Congenital Hypothyroidism (CH) and Dyshormonogenesis (DH) by using targeted next-generation sequencing (TNGS).

STUDY DESIGN

We studied 19 well-characterized patients diagnosed with CH and DH by targeted NGS including genes involved in thyroid hormone production. The pathogenicity of novel mutations was assessed based on in silico prediction tool results, functional studies when possible, variant location in important protein domains, and a review of the recent literature.

RESULTS

TNGS with variant prioritization and detailed assessment identified likely disease-causing mutations in 10 patients (53%). Monogenic defects most often involved TG, followed by DUOXA2, DUOX2, and NIS and were usually homozygous or compound heterozygous. Our review shows the importance of the detailed phenotypic description of patients and accurate analysis of variants to provide a molecular diagnosis.

CONCLUSIONS

In a clinically well-characterized cohort, TNGS had a diagnostic yield of 53%, in accordance with previous studies using a similar strategy. TG mutations were the most common genetic defect. TNGS identified gene mutations causing DH, thereby providing a rapid and cost-effective genetic diagnosis in patients with CH due to DH.

TUBB1 mutations cause thyroid dysgenesis associated with abnormal platelet physiology

The genetic causes of congenital hypothyroidism due to thyroid dysgenesis (TD) remain largely unknown. We identified three novel TUBB1 gene mutations that co‐segregated with TD in three distinct families leading to 1.1% of TUBB1 mutations in TD study cohort. TUBB1 (Tubulin, Beta 1 Class VI) encodes for a member of the β‐tubulin protein family. TUBB1 gene is expressed in the developing and adult thyroid in humans and mice. All three TUBB1 mutations lead to non‐functional α/β‐tubulin dimers that cannot be incorporated into microtubules. In mice, Tubb1 knock‐out disrupted microtubule integrity by preventing β1‐tubulin incorporation and impaired thyroid migration and thyroid hormone secretion. In addition, TUBB1 mutations caused the formation of macroplatelets and hyperaggregation of human platelets after stimulation by low doses of agonists. Our data highlight unexpected roles for β1‐tubulin in thyroid development and in platelet physiology. Finally, these findings expand the spectrum of the rare paediatric diseases related to mutations in tubulin‐coding genes and provide new insights into the genetic background and mechanisms involved in congenital hypothyroidism and thyroid dysgenesis.

Successful off-label sulfonylurea treatment of neonatal diabetes mellitus due to chromosome 6 abnormalities

Chromosome 6 abnormalities such as paternal uniparental isodisomy, paternal 6q24 duplication, and maternal DMR (differentially methylated region) hypomethylation are a common cause of transient neonatal diabetes mellitus (TNDM). Oral sulfonylurea (SU) is used off-label to treat permanent neonatal diabetes mellitus owing to potassium channel mutation but has not been evaluated in TNDM. Our objective was to evaluate the efficacy and safety of SU therapy in chromosome 6-related TNDM. Description of 3 case reports and literature review was the subject of the study. SU therapy was successful in 2 patients (initiated during neonatal life in 1 patient and during relapse in the other) but failed in the other despite the use of high dosage. The literature review identified 11 cases of patients with chromosome 6-related TNDM treated with SU, including 4 treated before remission and 7 after the relapse. SU therapy was consistently effective, although 4 patients treated after the relapse required multiple oral medications. None of the patients needed associated insulin therapy. No side effects of SU or complications of diabetes were reported. SU seems effective and safe in chromosome 6-related TNDM treatment when used to treat the initial episode of diabetes or the relapse. It improves patients' and families' quality of life. SU is available only as oral tablets. A pediatric dosage form would facilitate the treatment of neonates and infants.

Mutations in BOREALIN cause thyroid dysgenesis

Congenital hypothyroidism is the most common neonatal endocrine disorder and is primarily caused by developmental abnormalities otherwise known as thyroid dysgenesis (TD). We performed whole exome sequencing (WES) in a consanguineous family with TD and subsequently sequenced a cohort of 134 probands with TD to identify genetic factors predisposing to the disease. We identified the novel missense mutations p.S148F, p.R114Q and p.L177W in the BOREALIN gene in TD-affected families. Borealin is a major component of the Chromosomal Passenger Complex (CPC) with well-known functions in mitosis. Further analysis of the missense mutations showed no apparent effects on mitosis. In contrast, expression of the mutants in human thyrocytes resulted in defects in adhesion and migration with corresponding changes in gene expression suggesting others functions for this mitotic protein. These results were well correlated with the same gene expression pattern analysed in the thyroid tissue of the patient with BOREALIN-p.R114W. These studies open new avenues in the genetics of TD in humans.

Update of Thyroid Developmental Genes

Thyroid dysgenesis (TD) is the most common cause of congenital hypothyroidism in iodine-sufficient regions and includes a spectrum of developmental anomalies. The genetic components of TD are complex. Although a sporadic disease, advances in developmental biology have revealed monogenetic forms of TD. Inheritance is not based on a simple Mendelian pattern and additional genetic elements might contribute to the phenotypic spectrum. This article summarizes the key steps of normal thyroid development and provides an update on responsible genes and underlying mechanisms of TD. Up-to-date technologies in genetics and biology will allow us to advance in our knowledge of TD.

Down syndrome and nonautoimmune hypothyroidisms in neonates and infants

Down syndrome is characterized by a high prevalence of thyroid dysfunction during childhood. In this paper, we review the different kinds of thyroid dysfunction that occur excluding those of autoimmune origin: congenital hypothyroidism (elevated plasma TSH with low plasma T4 occurring at birth usually detected by neonatal screening), subclinical hypothyroidism (elevated plasma TSH with plasma T4 in the normal range, which can be congenital or acquired) and acquired primary hypothyroidism (elevated plasma TSH and low plasma T4 occurring after birth). These dysfunctions, while not due to autoimmunity, are of thyroidal origin. However, the mechanisms leading to these different thyroidal abnormalities have not been clearly defined; in particular, it is difficult to determine whether the different types of dysfunction have a common cause, or if the causes are distinct. Treatment is prescribed according to the type of thyroidal abnormality.

DYRK1A BAC transgenic mouse: a new model of thyroid dysgenesis in Down syndrome

The most common thyroid abnormality among Down syndrome (DS) children corresponds to a mildly elevated TSH, with T4 decreased or in the normal range and thyroid hypoplasia, from the neonatal period onward, which aggravate their mental impairment. Transgenic Dyrk1A mice, obtained by bacterial artificial chromosome engineering (mBACTgDyrk1A), have 3 copies of the Dyrk1A gene. The objective is to determine whether this transgenic Dyrk1A (Dyrk1A(+/++)) mouse is an adequate murine model for the study of thyroid dysgenesis in DS. Embryonic thyroid development from embryonic day 13.5 (E13.5) to E17.5 was analyzed in wild-type (WT) and Dyrk1A(+/++) mice by immunofluorescence with anti-Nkx2-1, anti-thyroglobulin, and anti-T4 antibodies, markers of early thyroid development, hormonogenesis, and final differentiation, respectively. The expression of transcription factors Nkx2-1, Pax8, and Foxe1 involved in thyroidogenesis were studied by quantitative RT-PCR at the same embryonic stages. We then compared the adult phenotype at 8 to 12 weeks in Dyrk1A(+/++) and WT mice for T4 and TSH levels, thyroidal weight, and histological analysis. Regarding thyroidal development, at E15.5, Dyrk1A(+/++) thyroid lobes are double the size of WT thyroids (P = .01), but the thyroglobulin stained surface in Dyrk1A(+/++) thyroids is less than a third as large at E17.5 (P = .04) and their differentiated follicular surface half the size (P = .004). We also observed a significant increase in Nkx2-1, Foxe1, and Pax8 RNA levels in E13.5 and E17.5 Dyrk1A(+/++) embryonic thyroids. Dyrk1A(+/++) young adult mice have significantly lower plasma T4 (2.4 ng/mL versus WT, 3.7 ng/mL; P = 0.019) and nonsignificantly higher plasma TSH (114 mUI/L versus WT, 73mUI/L; P = .09). In addition, their thyroids are significantly heavier (P = .04) and exhibit large disorganized regions. Dyrk1A overexpression directly leads to thyroidal embryogenetic, functional and morphological impairment. The young adult thyroid phenotype is probably a result of embryogenetic impairment. The Dyrk1A(+/++) mouse can be considered a suitable study model for thyroid dysgenesis in DS.

Adrenal enzyme impairment in neonates and adolescents treated with ritonavir and protease inhibitors for HIV exposure or infection

BACKGROUND

Human deficiency virus (HIV) protease inhibitors (PIs) are widely used drugs whose effects are pharmacologically enhanced by ritonavir, a potent cytochrome P450 inhibitor. We reported previously that prophylactic postnatal ritonavir-PI therapy in HIV-exposed neonates was associated with increases in plasma 17-hydroxyprogesterone (17-OHP) and dehydroepiandrosterone sulfate (DHEA-S).

AIMS

To further investigate adrenal function in neonates and adolescents given ritonavir-PI.

METHODS

Adrenal function was assessed prospectively in 3 HIV-exposed neonates given short-term prophylactic treatment and 3 HIV-infected adolescents given long-term treatment. Plasma cortisol, 17-OHP, 17-OH-pregnenolone, DHEA-S, and androstenedione were measured before and after ACTH administration.

RESULTS

None of the patients had clinical signs of adrenal dysfunction. The only neonate exposed to ritonavir-PI in utero had up to 3-fold increases in plasma 17-OHP. Increases in 17-OH-pregnenolone of up to 3.1-fold were noted in 4 of the 6 patients, and all 6 patients had elevations in DHEA-S (up to 20.4-fold increase) and/or DHEA (up to 4.7-fold) and/or androstenedione (up to 5.2-fold). All these parameters improved after treatment completion.

CONCLUSION

Neonates and adolescents given ritonavir-PI exhibit a similar adrenal dysfunction profile consistent with an impact on multiple adrenal enzymes. These abnormalities require evaluation, given the potentially long exposure times.

Dyrk1A induces pancreatic β cell mass expansion and improves glucose tolerance

Type 2 diabetes is caused by a limited capacity of insulin-producing pancreatic β cells to increase their mass and function in response to insulin resistance. The signaling pathways that positively regulate functional β cell mass have not been fully elucidated. DYRK1A (also called minibrain/MNB) is a member of the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family. A significant amount of data implicates DYRK1A in brain growth and Down syndrome, and recent data indicate that Dyrk1A haploinsufficient mice have a low functional β cell mass. Here we ask whether Dyrk1A upregulation could be a way to increase functional β cell mass. We used mice overexpressing Dyrk1A under the control of its own regulatory sequences (mBACTgDyrk1A). These mice exhibit decreased glucose levels and hyperinsulinemia in the fasting state. Improved glucose tolerance is observed in these mice as early as 4 weeks of age. Upregulation of Dyrk1A in β cells induces expansion of β cell mass through increased proliferation and cell size. Importantly, mBACTgDyrk1A mice are protected against high-fat-diet-induced β cell failure through increase in β cell mass and insulin sensitivity. These studies show the crucial role of the DYRK1A pathway in the regulation of β cell mass and carbohydrate metabolism in vivo. Activating the DYRK1A pathway could thus represent an innovative way to increase functional β cell mass.

Dyrk1a haploinsufficiency induces diabetes in mice through decreased pancreatic beta cell mass

AIMS/HYPOTHESIS

Growth factors and nutrients are important regulators of pancreatic beta cell mass and function. However, the signalling pathways by which these factors modulate these processes have not yet been fully elucidated. DYRK1A (also named minibrain/MNB) is a member of the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family that has been conserved across evolution. A significant amount of data implicates DYRK1A in brain growth and function, as well as in neurodegenerative processes in Alzheimer's disease and Down's syndrome. We investigated here whether DYRK1A would be an attractive candidate for beta cell growth modulation.

METHODS

To study the role of DYRK1A in beta cell growth, we used Dyrk1a-deficient mice.

RESULTS

We show that DYRK1A is expressed in pancreatic islets and provide evidence that changes in Dyrk1a gene dosage in mice strongly modulate glycaemia and circulating insulin levels. Specifically, Dyrk1a-haploinsufficient mice show severe glucose intolerance, reduced beta cell mass and decreased beta cell proliferation.

CONCLUSIONS/INTERPRETATION

Taken together, our data indicate that DYRK1A is a critical kinase for beta cell growth as Dyrk1a-haploinsufficient mice show a diabetic profile.

A novel FOXE1 mutation (R73S) in Bamforth-Lazarus syndrome causing increased thyroidal gene expression

BACKGROUND

Homozygous loss-of-function mutations in the FOXE1 gene have been reported in several patients with partial or complete Bamforth-Lazarus syndrome: congenital hypothyroidism (CH) with thyroid dysgenesis (usually athyreosis), cleft palate, spiky hair, with or without choanal atresia, and bifid epiglottis. Here, our objective was to evaluate potential functional consequences of a FOXE1 mutation in a patient with a similar clinical phenotype.

METHODS

FOXE1 was sequenced in eight patients with thyroid dysgenesis and cleft palate. Transient transfection was performed in HEK293 cells using the thyroglobulin (TG) and thyroid peroxidase (TPO) promoters in luciferase reporter plasmids to assess the functional impact of the FOXE1 mutations. Primary human thyrocytes transfected with wild type and mutant FOXE1 served to assess the impact of the mutation on endogenous TG and TPO expression.

RESULTS

We identified and characterized the function of a new homozygous FOXE1 missense mutation (p.R73S) in a boy with a typical phenotype (athyreosis, cleft palate, and partial choanal atresia). This new mutation located within the forkhead domain was inherited from the heterozygous healthy consanguineous parents. In vitro functional studies in HEK293 cells showed that this mutant gene enhanced the activity of the TG and TPO gene promoters (1.5-fold and 1.7-fold respectively vs. wild type FOXE1; p<0.05), unlike the five mutations previously reported in Bamforth-Lazarus syndrome. The gain-of-function effect of the FOXE1-p.R73S mutant gene was confirmed by an increase in endogenous TG production in primary human thyrocytes.

CONCLUSION

We identified a new homozygous FOXE1 mutation responsible for enhanced expression of the TG and TPO genes in a boy whose phenotype is similar to that reported previously in patients with loss-of-function FOXE1 mutations. This finding further delineates the role for FOXE1 in both thyroid and palate development, and shows that enhanced gene activity should be considered among the mechanisms underlying Bamforth-Lazarus syndrome.

THE USE OF TELEMEDICINE TO ASSESS AND ADVISE PATIENTS REGARDING DIETARY TREATMENT OF HYPERPHOSPHATAEMIA

Satellite units have the benefit of being local to patients and easily accessible. The main hospital where the dietitians are based is some distance away from the satellite unit. This has traditionally made it more difficult for the dietitians to assess satellite unit patients other than at set times when all the patients are assessed and advised in one visit. The aim of the telemedicine unit was to make dietary assessment of satellite unit patients easier by reducing travel time and to be more accessible to patients at times when visits by the dietitian were not scheduled. Telemedicine units were linked from the main hospital to the satellite unit. Fourteen patients were assessed and advised via this method and of these patients 8 patients were seen for help with their hyperphosphataemia. Phosphate levels on referral were 2.46 +/- 0.47mmols/l and by the following month after review by the dietitian had decreased to 2.06 +/- 0.43mmols/l (p=0.01) and 1.96 +/- 0.16mmols/l by month 6 (p=0.02). This small study shows that the telemedicine unit is an effective way to assess patients and communicate information. Travel time has been saved and patients have had the benefit of receiving dietary information soon after their raised phosphate result rather than having to wait for the next scheduled visit by the dietitian.

Five-year follow-up of a cohort of people with their first diabetic foot ulcer: the persistent effect of depression on mortality

AIMS/HYPOTHESIS

Depressive disorders are associated with mortality within 18 months of presentation of diabetic foot ulcers (DFU). The main aim of this study was to determine whether depressive disorder is still associated with increased mortality in people with their first foot ulcer at 5 years.

METHODS

This is a 5-year follow-up of a cohort of 253 patients presenting with their first DFU. At baseline, the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) 2.1 was used to define those who met DSM-IV (Diagnostic and Statistical Manual 4th edition) criteria for depressive disorder. Cox regression analysis controlled for potential covariates: age, sex, marital status, socioeconomic status, smoking, mean HbA(1c), diabetes complications and ulcer severity. The main outcome was mortality at 5 years.

RESULTS

The prevalence of DSM-IV depressive disorder at baseline was 32.2% (n = 82). There were 92 (36.4%) deaths over the 5 years of follow-up. In the Cox regression (n = 246), after adjusting for covariates, baseline DSM-IV depressive disorder was significantly associated with a twofold increased risk of mortality for any depressive episode (HR 2.09, 95% CI 1.34, 3.25), minor (HR 1.93, 95% CI 1.00, 3.74) or major depressive disorders (HR 2.18, 95% CI 1.31, 3.65), compared with patients who were not depressed.

CONCLUSIONS/INTERPRETATION

Depression is associated with a persistent twofold increased risk of mortality in people with their first DFU at 5 years.

Association of prenatal and postnatal exposure to lopinavir-ritonavir and adrenal dysfunction among uninfected infants of HIV-infected mothers

CONTEXT

Lopinavir-ritonavir is a human immunodeficiency virus 1 (HIV-1) protease inhibitor boosted by ritonavir, a cytochrome p450 inhibitor. A warning about its tolerance in premature newborns was recently released, and transient elevation of 17-hydroxyprogesterone (17OHP) was noted in 2 newborns treated with lopinavir-ritonavir in France.

OBJECTIVE

To evaluate adrenal function in newborns postnatally treated with lopinavir-ritonavir.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cross-sectional analysis of the database from the national screening for congenital adrenal hyperplasia (CAH) and the French Perinatal Cohort. Comparison of HIV-1-uninfected newborns postnatally treated with lopinavir-ritonavir and controls treated with standard zidovudine.

MAIN OUTCOME MEASURES

Plasma 17OHP and dehydroepiandrosterone-sulfate (DHEA-S) concentrations during the first week of treatment. Clinical and biological symptoms compatible with adrenal deficiency.

RESULTS

Of 50 HIV-1-uninfected newborns who received lopinavir-ritonavir at birth for a median of 30 days (interquartile range [IQR], 25-33), 7 (14%) had elevated 17OHP levels greater than 16.5 ng/mL for term infants (>23.1 ng/mL for preterm) on days 1 to 6 vs 0 of 108 controls having elevated levels. The median 17OHP concentration for 42 term newborns treated with lopinavir-ritonavir was 9.9 ng/mL (IQR, 3.9-14.1 ng/mL) vs 3.7 ng/mL (IQR, 2.6-5.3 ng/mL) for 93 term controls (P < .001). The difference observed in median 17OHP values between treated newborns and controls was higher in children also exposed in utero (11.5 ng/mL vs 3.7 ng/mL; P < .001) than not exposed in utero (6.9 ng/mL vs 3.3 ng/mL; P = .03). The median DHEA-S concentration among 18 term newborns treated with lopinavir-ritonavir was 9242 ng/mL (IQR, 1347-25,986 ng/mL) compared with 484 ng/mL (IQR, 218-1308 ng/mL) among 17 term controls (P < .001). The 17OHP and DHEA-S concentrations were positively correlated (r = 0.53; P = .001). All term newborns treated with lopinavir-ritonavir were asymptomatic, although 3 premature newborns experienced life-threatening symptoms compatible with adrenal insufficiency, including hyponatremia and hyperkalemia with, in 1 case, cardiogenic shock. All symptoms resolved following completion of the lopinavir-ritonavir treatment.

CONCLUSION

Among newborn children of HIV-1-infected mothers exposed in utero to lopinavir-ritonavir, postnatal treatment with a lopinavir-ritonavir-based regimen, compared with a zidovudine-based regimen, was associated with transient adrenal dysfunction.