Vitamin D and calcium intakes in general pediatric populations: A French expert consensus paper.

OBJECTIVES: Nutritional vitamin D supplements are often used in general pediatrics. Here, the aim is to address vitamin D supplementation and calcium nutritional intakes in newborns, infants, children, and adolescents to prevent vitamin D deficiency and rickets in general populations. STUDY DESIGN: We formulated clinical questions relating to the following categories: the Patient (or Population) to whom the recommendation will apply; the Intervention being considered; the Comparison (which may be "no action," placebo, or an alternative intervention); and the Outcomes affected by the intervention (PICO). These PICO elements were arranged into the questions to be addressed in the literature searches. Each PICO question then formed the basis for a statement. The population covered consisted of children aged between 0 and 18 years and premature babies hospitalized in neonatology. Two groups were assembled: a core working group and a voting panel from different scientific pediatric committees from the French Society of Pediatrics and national scientific societies. RESULTS: We present here 35 clinical practice points (CPPs) for the use of native vitamin D therapy (ergocalciferol, vitamin D2 and cholecalciferol, vitamin D3) and calcium nutritional intakes in general pediatric populations. CONCLUSION: This consensus document was developed to provide guidance to health care professionals on the use of nutritional vitamin D and dietary modalities to achieve the recommended calcium intakes in general pediatric populations. These CPPs will be revised periodically. Research recommendations to study key vitamin D outcome measures in children are also suggested.

Exploring the genetic causes of isolated short stature. What has happened to idiopathic short stature?

Statural growth is underpinned by development of the growth plate during the process of endochondral ossification, which is strongly regulated by numerous local factors (intracellular, paracrine and extracellular matrix factors) and systemic factors (nutrition, hormones, proinflammatory cytokines and extracellular fluids). This explains why growth retardation can be associated with numerous pathologies, particularly genetic syndromes, hormonal or inflammatory conditions, or gastrointestinal disorders having a nutritional impact. However, in most cases (80%), no specific aetiology is found after clinical investigation and conventional additional tests have been carried out. In such cases, "idiopathic" short stature is diagnosed, which includes patients presenting with constitutional delay of growth and development and familial short stature, but also patients with very subtle constitutional skeletal dysplasia which are not easily identifiable. In recent years, new methods of genetic investigation (e.g. gene panels, exome or genome sequencing) have made it possible to identify many genetic variants associated with apparently isolated short stature. Indeed, it is still difficult to estimate the proportion of patients presenting with idiopathic short stature for which a molecular diagnosis of monogenic conditions could be made. This estimate varies hugely depending on the thoroughness of the clinical, laboratory and radiological assessments performed prior to molecular analysis, since retrospective analysis of positive cases usually reveals subtle signs of underlying syndromes or rare skeletal disorders. Molecular diagnosis in children is important to be able to offer genetic counselling and to organise patient management. Moreover, improved understanding of the molecular basis of these cases of short stature opens up numerous possibilities for more specific treatments targeting the growth plate. © 2022 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Guidelines for the management of children at risk of secondary bone fragility: Expert opinion of a French working group.

The current French national guidelines were elaborated by a working group consisting of experts in the field of pediatric endocrinology, rheumatology, hepatogastroenterology, nephrology, and pneumology. A systematic search was undertaken of the literature published between 2008 and 2018 and indexed in PubMed. The recommendations developed were then validated by an external evaluation group comprising representatives from the various highly specialized fields in pediatrics, representatives of the societies and groups supporting the development of the guidelines, and representatives of different healthcare professions. The objective of these guidelines was to detail the current optimal management of children at risk of secondary bone fragility.

[Severe nutritional rickets in young children: Resurgence of an old disease]. / Rachitisme carentiel sévère du nourrisson : de nouveau d'actualité.

Nutritional rickets remains a significant public health issue for children worldwide. Although it has almost disappeared in industrialized countries following routine vitamin D supplementation, recent evidence suggests an increasing incidence, especially in young children. In addition to the classical clinical consequences on bone and the growth plate, rickets may also be associated with life-threatening neurological and cardiac complications in the most severe forms. Consequently, early screening and treatment are required. Here, we report the case of a 2-year-old child who presented with severe nutritional rickets associated with seizure and cardiomyopathy. Family screening revealed rickets in all the siblings. This case report emphasizes the importance of being aware of this disease, notably in population with sociocultural risk factors.

[Loeys-Dietz syndrome (TGFßR2 mutation) in a 4-year-old child with thoracic aortic aneurysm]. / Syndrome de Loeys-Dietz (mutation TGFßR2) chez une enfant de 4ans avec anévrysme de l'aorte thoracique.

Loeys-Dietz syndrome is a rare form of connective tissue disorder, whose clinical features can resemble those of Marfan syndrome, but with a more unpolished appearance. Recently brought out, this pathology remains little known; however, its consequences may be dramatic. We report on the case of a 4-year-old girl followed for a congenital hip dislocation, in which a systematic exam found increased cutaneous elasticity and a bifid uvula, suggesting a connective tissue disorder. Symptoms were unpolished, as the child's height was normal, without any positive cardiac, rheumatological, or ophthalmological family history. Cardiovascular tests found a thoracic aortic aneurysm at the Valsalva sinus (26mm, Z-score=+4.24). A genetic investigation found a TGFßR2 gene mutation, leading to the diagnosis of Loeys-Dietz syndrome type 2. Skeletal damage associated with bifid uvula and/or hypertelorism and an aneurysm of the ascending aorta should guide the genetic investigation to the search for TGF-ß vasculopathy such as Loeys-Dietz syndrome.

[Morgagni-Larrey diaphragmatic hernia in a 3-month-old child affected by Marfan syndrome]. / Hernie de la fente de Larrey chez un nourrisson de trois mois atteint du syndrome de Marfan.

The authors report on a case of diaphragmatic hernia occurring in a 3-month-old child affected by Marfan syndrome. Diagnosis was made on a chest X-ray and cardiac ultrasounds, performed because of the association of poor general condition, failure to thrive, and signs of respiratory distress. As a reminder, we emphasize the association between Marfan disease and diaphragmatic hernias as well as the diagnostic approach to reach an appropriate diagnosis.

Systematic molecular and cytogenetic screening of 100 patients with marfanoid syndromes and intellectual disability.

The association of marfanoid habitus (MH) and intellectual disability (ID) has been reported in the literature, with overlapping presentations and genetic heterogeneity. A hundred patients (71 males and 29 females) with a MH and ID were recruited. Custom-designed 244K array-CGH (Agilent®; Agilent Technologies Inc., Santa Clara, CA) and MED12, ZDHHC9, UPF3B, FBN1, TGFBR1 and TGFBR2 sequencing analyses were performed. Eighty patients could be classified as isolated MH and ID: 12 chromosomal imbalances, 1 FBN1 mutation and 1 possibly pathogenic MED12 mutation were found (17%). Twenty patients could be classified as ID with other extra-skeletal features of the Marfan syndrome (MFS) spectrum: 4 pathogenic FBN1 mutations and 4 chromosomal imbalances were found (2 patients with both FBN1 mutation and chromosomal rearrangement) (29%). These results suggest either that there are more loci with genes yet to be discovered or that MH can also be a relatively non-specific feature of patients with ID. The search for aortic complications is mandatory even if MH is associated with ID since FBN1 mutations or rearrangements were found in some patients. The excess of males is in favour of the involvement of other X-linked genes. Although it was impossible to make a diagnosis in 80% of patients, these results will improve genetic counselling in families.

Short- and long-term outcome of patients with pseudo-vitamin D deficiency rickets treated with calcitriol.

BACKGROUND: Pseudo-vitamin D deficiency rickets (PDDR; OMIM 264700) is a rare autosomal recessive disorder caused by mutations in the CYP27B1 gene, leading to an inability to synthesize 1α,25-dihydroxyvitamin D(3) (calcitriol). The long-term (>1 yr) effects of calcitriol replacement treatment have not been reported. MATERIALS AND METHODS: Thirty-nine patients (20 females) with PDDR received calcitriol for periods of 2.0-26 yr. In 21 patients, data were available at diagnosis and during the first 2 yr of treatment with calcitriol. Twenty-five patients had reached their final height at the time of this analysis. RESULTS: The most common presenting features were active rickets, neurological signs, and short stature. Treatment with calcitriol resulted in the normalization of biochemical parameters and mean lumbar spine areal bone mineral density z-scores within 3 months, whereas height z-scores increased more gradually. As to long-term effects, adult patients who had received calcitriol before the pubertal growth spurt (n = 11) had normal height, whereas patients who were treated with calcitriol only after puberty (n = 14) on average were short (height z-score -2.2). Lumbar spine areal bone mineral density z-scores were normal in all patients who had achieved final height. Nine women had 19 pregnancies, which all were without complications. All newborns were eucalcemic at birth. CONCLUSION: Treatment with calcitriol started in infancy results in short- and long-term correction of all clinical, biochemical, and radiological abnormalities related to PDDR.

[Delayed puberty]. / Retard pubertaire.

Delayed puberty is defined in girls by the absence of breast development beyond 13 years old and in boys by the absence of testicular enlargement (< 4 ml) beyond 14 years old. Simple investigations lead to the diagnosis of central or peripheral hypogonadism and constitutional delay of puberty. In girls, delayed puberty is rare and often organic, and then Turner syndrome should be systematically suspected. In boys, delayed puberty is often constitutional and functional. Treatment is etiologic when possible, hormonal replacement therapy (oestrogen in girls and testosterone in boys) and psychological management.

Isolated lymphocytic infiltration of pituitary stalk preceding the diagnosis of germinoma in 2 prepubertal children treated with growth hormone.

We report the clinical course of 2 patients with central diabetes insipidus and evolving to panyhypopituitarism which prompted the diagnosis of an isolated pituitary stalk thickening (PST). In both patients, all etiological investigations were normal and the first biopsy revealed an isolated lymphocytic infiltrate with no sign of malignancy. Close clinical follow-up accompanied by serial brain MRIs was proposed to determine a precise diagnosis and for early detection and treatment of neoplastic disease. In our first case, the diagnosis of germinoma was made 9 months after the PST diagnosis owing to tumor progression. In the second case, the time course was even longer with the diagnosis of germinoma 6 years following initial presentation. In these cases, it is speculated that the lymphocytic infiltrates represent the first sign of a host reaction to an occult germinoma. To our knowledge, this is the third case reported of lymphocytic infiltrates preceding a germinoma in a prepubertal girl, and the only case reported in a prepubertal boy. These cases underline the difficulties in establishing the diagnosis of germinoma in a patient with isolated PST.

Prevalence of IGF1 deficiency in prepubertal children with isolated short stature.

BACKGROUND/AIMS: 'Primary IGF1 deficiency (IGFD)' is defined by low levels of IGF1 without a concomitant impairment in GH secretion in the absence of secondary cause. The aims of this study were to evaluate the prevalence of non-GH deficient IGFD in prepubertal children with isolated short stature (SS) and to describe this population. METHODS: This retrospective study included all children with isolated SS seen in our Pediatric Endocrinology Unit from January 2005 to December 2007. Children were included based on the following criteria: i) SS with current height SDS < or = -2.5, ii) age > or = 2 years, and iii) prepubertal status. Exclusion criteria were: i) identified cause of SS and ii) current or past therapy with rhGH. IGF1-deficient children were defined as children without GH deficiency and with IGF1 levels below or equal to -2 SDS. RESULTS: Among 65 children with isolated SS, 13 (20%) had low IGF1 levels, consistent with a diagnosis of primary IGFD, four of which were born small for gestational age and nine were born appropriate for gestational age. When compared with non-IGFD children, IGFD children had higher birth weight (-0.7 vs -1 SDS, P=0.02) and birth height (-1.7 vs -2 SDS, P=0.04) and more delayed bone age (2.6 vs 1.7 years, P=0.03). CONCLUSION: The prevalence of primary IGFD was 20% in children with isolated SS. Concerning the pathophysiology, our study emphasizes that IGFD in some children may be secondary to nutritional deficiency or to maturational delay.

User trial of Easypod, an electronic autoinjector for growth hormone.

OBJECTIVE: A new electronic injection device, the Easypod, has been developed to administer growth hormone (GH). This study assessed the use of this device in common practice. MATERIALS AND METHODS: Results are from the French arm (one centre) of an international, open-label, uncontrolled study. Subjects were children already using, or about to start, GH therapy. Children used the Easypod device for 60 days. The main outcome measures were patients' or, if appropriate, their parents' qualitative overall impression of the device and the usefulness of its features after 15 days' use, as evaluated by questionnaire. RESULTS: At day 15, all participants (20/20) described their overall impression of the Easypod device as "good" or "very good". All participants rated the display of the remaining drug in the cartridge, the preprogrammed dosing, the onscreen instructions and the automatic-needle attachment as "useful" or "very useful". The device's audible/visible signals and customisable injection depth and speed were each rated as "useful" or "very useful" by 19/20 participants and the skin sensor, customisable needle-insertion speed and dose-injection confirmation were each rated as such by 18/20 participants. Electronic display of the date and time of the last injection and the dose history were considered "useful" or "very useful" by 17/20 and 15/20 participants, respectively. At day 60, 17/17 respondents expressed a preference for continuing to use the device. CONCLUSION: These results show that the features of Easypod are considered useful in routine practice and the majority of participants expressed a desire to continue using the device.

[New molecular mechanisms of growth hormone insensitivity]. / Nouveaux mécanismes moléculaires impliqués dans l'insensibilité à l'hormone de croissance.

Growth hormone (GH), secreted by the anterior pituitary into the circulation, binds to membrane receptors in target tissues to stimulate body growth; most of its effects is mediated by the insulin-like growth factor 1 (IGF-1). In addition to promoting growth, GH has important metabolic actions. The syndrome of GH insensitivity (GHI) was first identified in 1966 by Laron et al. in three children with clinical phenotype characteristic of growth hormone deficiency but associated with elevated serum concentration of GH. Direct evidence of a GH receptor (GHR) abnormality was provided in 1989. More recently, molecular abnormalities in the postreceptor signalling mechanism were found. Mutations of signal transducer and activator of transcription 5b (Stat5b) were reported in patients with growth retardation and primary immunodeficiency. Mutations of the tyrosin phosphatase Shp2 were identified in patients affected by Noonan syndrome characterized by short stature, cardiopathy and increased risk of leukaemia. The unmasking of the molecular bases for these defects will contribute greatly to our future understanding of both normal and aberrant growth. Moreover, this knowledge should bring insight on cancerogenesis or immunodeficiency caused by cytokines resistance.

[Growth follow-up of SGA children after 3 years of GH treatment]. / Suivi de la croissance chez les enfants de petite taille de naissance après 3 ans de traitement par hormone de croissance: l'expérience d'un centre français.

UNLABELLED: Eighty-five percent of children born with IUGR have spontaneous catch-up growth in the first 2 years of life; however, about 10 to 15% do not catch up. Numerous therapeutic trials have demonstrated the efficacy of GH treatment in these children. However, the duration of this treatment is still discussed. OBJECTIVE: The aim of this study was to describe the evolution of growth during and after the end of treatment. POPULATION AND METHODS: This study followed 33 children in our unit, treated with growth hormone under the French indication (3 years of treatment followed by 1 year off treatment) and with a mean follow-up of 3 years after cessation. RESULTS: During the 3 years of therapy, we confirmed an increase in growth velocity that resulted in a mean height above -2 standard deviation score (SDS) in 25 children at 3 years (mean height of 1.4 SDS). Among the 25 children who achieved a height above -2 SDS at three years and therefore stopped treatment, 15 resumed GH due to a secondary catch-down. Among children who didn't catch-up at 3 years, the continuation of GH treatment didn't seem to improve the growth.

Intracranial hypotension in a girl with Marfan syndrome: case report and review of the literature.

INTRODUCTION: A 14-year-old girl, followed in our department for Marfan syndrome, presented with postural headache for a month. Neurological examination was normal. The diagnosis of intracranial hypotension syndrome was suspected. DISCUSSION: Bilateral subdural hematomas were found on brain magnetic resonance imaging (MRI), and spinal MRI showed large lumbosacral arachnoid diverticula; no cerebrospinal fluid leaks could be found. Despite bed rest and hydration for 2 weeks, postural headache remained. Epidural blood patching was also performed. Subsequently, the patient became asymptomatic and could stand up after 1 day. Brain MRI did not find recurrent subdural hematoma after 1 month. Dural ectasia is one of the major criteria of Marfan syndrome, and it is often poorly symptomatic. Intracranial hypotension is a rare complication especially in children, and management is not standardized. In this case report, blood patching was sufficient. Further research into the diagnosis and management of spontaneous intracranial hypotension is required.

How do Shp2 mutations that oppositely influence its biochemical activity result in syndromes with overlapping symptoms?

Activating and inactivating mutations of SHP-2 are responsible, respectively, for the Noonan (NS) and the LEOPARD (LS) syndromes. Clinically, these developmental disorders overlap greatly, resulting in the apparent paradox of similar diseases caused by mutations that oppositely influence SHP-2 phosphatase activity. While the mechanisms remain unclear, recent functional analysis of SHP-2, along with the identification of other genes involved in NS and in other related syndromes (neurofibromatosis-1, Costello and cardio-facio-cutaneous syndromes), strongly suggest that Ras/MAPK represents the major signaling pathway deregulated by SHP-2 mutants. We discuss the idea that, with the exception of LS mutations that have been shown to exert a dominant negative effect, all disease-causing mutations involved in Ras/MAPK-mediated signaling, including SHP-2, might lead to enhanced MAPK activation. This suggests that a narrow range of MAPK signaling is required for appropriate development. We also discuss the possibility that LS mutations may not simply exhibit dominant negative activity.

[3D echocardiography of the ascending aorta in Marfan's syndrome]. / Echocardiographie 3D de l'aorte ascendante dans le syndrome de Marfan.

Marfan's syndrome is a cause of dilatation of the aorta, the main complication of which is dissection of the aorta. 2D echocardiography is the reference investigation for measuring the ascending aorta. Asymmetry of sinus dilatation makes a 3D approach necessary. Real time 3D echocardiography is a simple, non-invasive method which, by a biplane mode, allows measurement of the 3 sinuses of Valsalva. The aim of the study was to compare the 2D and 3D echocardiographic methods for measuring the ascending aorta. Fifteen patients (average age 12 +/- 8 years) with Marfan's syndrome were studied prospectively. The maximal 3D diameter was significantly greater than the 2D measurement (31.7 +/- 6.8 mm vs 29.9 +/- 6.6 mm, p< 0.005). In 4 patients, the difference was over 3 mm. The diameter between the right coronary and left coronary sinus was greater than the two others (right coronary-non coronary and left coronary-non coronary). The oldest 5 patients had an MRI aortic measurement very similar to that of 3D echocardiography (36.6 vs 36.7 mm). Real time 3D echocardiography in the biplane mode enables reliable and reproducible measurement of the aortic root in patients with Marfan's syndrome. Larger and multicenter studies are required to allow confirmation of the value of 3D echocardiography in the follow-up of these patients.