Hormone Research in Paediatrics最新文献

Background: Hypophosphatasia (HPP) is a rare genetic disorder caused by loss-of-function variants in the ALPL gene, leading to deficient tissue-nonspecific alkaline phosphatase (ALP) activity. This results in a distinctive biochemical profile marked by low serum ALP levels and elevated pyridoxal-5-phosphate (PLP). The clinical spectrum of HPP ranges from perinatal lethality to asymptomatic cases, presenting significant diagnostic and therapeutic challenges.

Summary: Diagnosis of HPP relies on identifying the characteristic biochemical signature (low ALP, high PLP), concomitant with skeletal (osteomalacia, rickets, pseudofracture) or extraskeletal (muscle weakness, musculoskeletal pain, dental) manifestations. Current diagnostic frameworks lack uniformity, highlighting the imperative for a standardized diagnostic approach. Molecular genetic testing plays a pivotal role in making the diagnosis of HPP, but difficulties persist in diagnosing milder cases and correlating genotypes with phenotypes. Comprehensive multidisciplinary care is indispensable, with enzyme replacement therapy (ERT) proving efficacious in severe cases and more nuanced management approaches for milder presentations. Overcoming challenges in ERT initiation, treatment response assessment, dose titrations, and long-term surveillance necessitates further refinement of management guidelines.

Key message: Mild forms of HPP and asymptomatic carriers of pathogenic ALPL variants pose substantial diagnosis and management challenges. Developing consensus-driven guidelines is crucial to enhance clinical outcomes and patient care.

Introduction: Growth acceleration during postnatal growth only occurs during puberty as a physiological event and during catch-up growth mediated by growth-promoting therapies in growth disorders. Here we report on novel observations of skeletal symptoms during treatment with erdafitinib, a tyrosine kinase inhibitor (TKI) prescribed on the basis of a compassionate-use program.

Methods: Analysis of anthropometric, biochemical, clinical, and radiographic data of patients with CNS tumors who revealed an unanticipated growth spurt with initiation of therapy with erdafitinib was performed retrospectively.

Results: Linear growth acceleration was independent of sex steroids and IGF1 levels, which is especially remarkable in the context of heavily pretreated pediatric neuro-oncology patients with severe growth impairment before initiation of therapy. Growth acceleration was accompanied by a distinct widening of the growth plate and enhanced metaphyseal mineralization shortly after the start of TKI therapy.

Conclusions: While targeted therapies including TKIs have become an essential part of adult cancer treatment, applications in children are still limited. Off-target effects specific to the pediatric population have been observed in various organ systems; however, knowledge about the effect of TKIs on the growing skeleton is scarce. Treatment with erdafitinib inhibits FGFR3-mediated effects and thus represents a very logical hypothetical framework of growth factor and sex steroid-independent growth acceleration.

Introduction: Achieving evidence-based, high-quality medical care is the overarching goal of healthcare quality management. Quality indicators (QIs) serve as proxies to show whether good quality is reached or not. This article describes the development of QI for the evaluation of healthcare quality in the area of differences of sex development (DSD).

Methods: Following the model of Donabedian, the aim was to develop QI to assess defined relevant aspects of the quality of structures, processes, and outcomes of care in DSD. Ten DSD clinical centres and two self-advocacy groups in Germany included in the DSDCare project were involved in the development of the QI and a benchmarking system. The development of the QI involved several structured steps: analysis of guidelines and recommendations, literature review, qualitative interviews with key stakeholders in the field of DSD, and patients or their carers. QIs were discussed in a multi-stage systematic consensus process and assessed in terms of their relevance, feasibility, and practicability.

Results: In a multi-stage systematic consensus process involving medical and psychological experts from a range of disciplines, people with DSD and their families, and representatives of self-advocacy groups, we have developed a set of 37 QIs (22 structure, seven process, and eight outcome quality). The QIs serve to evaluate care in the field of DSD and may add to the German criteria for certification of Centres for Rare Conditions formulated by the National Action League for People with Rare Diseases (NAMSE) in this area of expertise.

Conclusion: We have succeeded in developing and jointly adopting a set of QIs that consider a wide range of perspectives on the quality of care for people with DSD and their families. These QIs have been found to be relevant, feasible, and practicable, and they are now used for a yearly quality benchmarking in the participating DSD centres.

Background: Recent advances in insulin research open new avenues for treatment, both, for type 1 and type 2 diabetes. In developed countries, standardized "ultra-rapid-acting insulins" are now also used in addition to rapid-acting insulins. First- and second-generation basal analogs are available. Third-generation basal analogs, which only need to be applied once a week, are in the pipeline.

Summary: Second-generation "ultra-rapid-acting insulins" insulins with faster onset and offset of action may be particularly useful for multiple daily injections and automated insulin delivery systems. An improved time-action profile of bolus insulin would be able to cover the rapid increase in glucose after meals with a rapid fall thereafter to avoid postprandial hypoglycemia. The third-generation basal insulins allowing once-weekly dosing made major steps toward becoming a clinical reality. However, issues with insulin affordability and availability remain problematic even in more affluent countries. Biosimilar insulins products can provide people with additional safe, high-quality, and potentially cost-effective options for treating diabetes. Particularly in low-middle income countries insulin therapy is facing issues not only of access but also storage, lack of diabetes education, and stigma.

Key message: With the new bolus insulins, the physiological insulin secretion pattern can be mimicked better and better and hypoglycemia can be avoided. With the ever longer pharmacokinetic action profiles of the basal analogs, the injection frequency is reduced, which leads to better adherence and quality of life, but these insulins are not available for everyone who needs it worldwide.

Introduction: Growth patterns in Noonan syndrome (NS) remain relatively unknown. The objective of this study was to provide growth reference curves for patients with NS and identify correlations between their growth, genotype, and clinical features.

Methods: This was a 15-year-long, monocentric, observational, retrospective, non-interventional study. Children with NS followed up between 2005 and 2022 at "Bambino Gesù" Children's Hospital, Italy, were included and excluded if they had received growth hormone treatment. Comparison of growth curves of participants with NS versus the general Italian population and further genotypic analyses were performed.

Results: Overall, 190 eligible participants with NS were identified, with median (interquartile range) age of 14.01 (9.05-19.25) years (55.8% male). Cardiovascular anomalies were present in 85.3% of participants, most commonly pulmonary stenosis (52.6%) and atrial septal defects (36.8%); 48.1% of male participants had cryptorchidism. The most frequently detected mutations were in PTPN11 (66.3%) and SOS1 (13.9%). NS sex-specific centile curves for height, weight, body mass index, and height velocity were produced. For both sexes, the 50th percentile of height and weight for participants with NS overlapped with the 3rd percentile for the general Italian population. Both sexes with a PTPN11 mutation had a significantly lower height and weight than those with "other mutations" at 5 years old. No significant associations were observed between cardiac anomalies and PTPN11 mutation status.

Conclusion: We present longitudinal data describing growth curves and trends, the natural history, and genotypes of the NS population, which provide a useful tool for clinicians in the management of NS.

Introduction: While the influence of various factors on classical androgen synthesis in children and adolescents and its impact on puberty has been widely investigated, there appear to be gaps and contradictory findings regarding the association of overweight and obesity with the synthesis of adrenal-derived 11-oxygenated androgen (11-OA) serum levels. With this study, we aimed to examine how overweight and obesity affect 11-OA serum levels during puberty in a large cohort of children and adolescents.

Methods: Our cohort comprised 1,054 healthy children aged 6 to 19 years providing serum samples at a total of 1,734 visits. Liquid chromatography-tandem mass spectrometry was used to quantify 11-ketotestosterone (11-KT), 11-ketoandrostendione (11-KA4), 11-ß-hydroxytestosterone (11-OHT), 11-ß-hydroxyandrostendione (11-OHA4), testosterone, androstenedione, and DHEAS. In addition, we assessed BMI-SDSs; skinfold thicknesses; and Tanner stages. The significance level α was set to α=0.05.

Results: Increases in 11-KT, 11-KA4, 11-OHT, and 11-OHA4 levels were observed in boys and girls during puberty. 11-KT (ß=0.2, p<0.001), 11-KA4 (ß=0.16, p<0.001) and 11-OHA4 (ß=0.12, p=0.003) were positively correlated with BMI in boys age 13 and under. 11-KT (ß=0.1, p=0.047) was positively correlated with BMI in girls age 11 and under. 11-OHT was positively correlated with BMI independent of age (boys 13 and under: ß=0.17, p<0.001; over 13 years: ß=0.14, p=0.001; girls 11 and under: ß=0.17, p<0.001; over 11 years: ß=0.18, p<0.001).

Conclusion: We found increasing 11-OA serum levels throughout all Tanner stages. 11-OAs were observed to be associated with BMI and skinfold thickness, suggesting that overweight and obesity may be associated with pubertal alterations in 11-OA serum levels.

Introduction: Childhood hypophosphatemia is a rare condition and may be caused by malabsorption, malignancies, or genetic factors. Prolonged hypophosphatemia leads to impaired growth and radiographic signs of rickets.

Methods: We performed a detailed clinical and genetic evaluation of an adolescent boy with repeatedly low plasma phosphate concentrations (below 0.60 mmol/L) and growth failure.

Results: At 14 years, the patient presented with decelerating growth and delayed puberty. Biochemistry showed hypophosphatemia due to increased urinary phosphate loss; kidney function and vitamin D status were normal. Radiographs showed mild metaphyseal changes. A gene panel for known genetic hypophosphatemia was negative. Trio exome analysis followed by Sanger sequencing identified a pathogenic heterozygous de novo stop-gain variant in PRPF8 gene, c.5548C>T p.(Arg1850*), in the conserved RNase H homology domain. PRPF8 encodes the pre-RNA protein 8, which has a role in RNA processing. Heterozygous PRPF8 variants have been associated with retinitis pigmentosa and neurodevelopmental disorders but not with phosphate metabolism. The patient underwent growth hormone (GH) stimulation tests which confirmed GH deficiency. Head MRI indicated partially empty sella. GH treatment was started at 15 years. Surprisingly, phosphate metabolism normalized during GH treatment, suggesting that hypophosphatemia was at least partly secondary to GH deficiency.

Conclusion: The evaluation of an adolescent with profound long-term hypophosphatemia revealed a pituitary developmental defect associated with a stop-gain variant in PRPF8. Hypophosphatemia alleviated with GH treatment. The pathological PRPF8 variant may contribute to abnormal pituitary development; however, its role in phosphate metabolism remains uncertain.

Introduction: Thyroid dyshormonogenesis (TDH) is a subgroup of congenital hypothyroidism with recessive inheritance resulting from disease-causing variants in thyroid hormone biosynthesis pathway genes, like DUOX2, TG, TPO, SLC5A5, SLC26A4, IYD, DUOXA2, and SLC26A7. Thyroid peroxidase (TPO) is a crucial enzyme involved in thyroid hormone biosynthesis and is one of the frequently mutated genes in patients with TDH. The purpose of the study was to describe the in silico and functional characterization of novel variants in TPO gene identified in patients with TDH.

Methods: We performed exome sequencing in Indian patients with TDH. In the current study, we describe the results of patients with TPO gene mutations. Exome sequencing results were further analysed by Sanger sequencing, computational studies, and in vitro functional studies such as immunofluorescence and enzyme assay.

Results: We identified nine biallelic disease-causing variants in the TPO gene in 12 patients from nine unrelated Indian families. Eight of the nine variants were novel. No recurrent variants were identified. Computational analysis of six missense variants showed that these amino acid substitutions caused changes in non-covalent interactions with the adjacent residues that may affect the TPO protein structure and function. In vitro experimental data using immunofluorescence assay showed that these variants did not affect the plasma membrane localization of the TPO protein but caused a significant loss of TPO enzymatic activity compared to the wild type.

Conclusion: Our study revealed multiple novel pathogenic variants in TPO gene in Indian patients, thereby expanding the genotype spectrum. Functional studies helped us to reveal the pathogenicity of the missense variants.

Introduction: In this article, the importance of holistic care is highlighted trough the case of a 10-year-old female with diabetes type 1 presenting with recurrent severe hypoglycemia.

Case presentation: A 10-year-old female, with type 1 diabetes mellitus for 2 years, was hospitalized because of persistent hypoglycemia. At time of presentation, the patient was getting her insulin through an automated insulin delivery device. She came to the emergency room because of severe hypoglycemia despite adequate administration of glucagon intranasal and oral sugar solutions. The patient was hospitalized to resolve the hypoglycemia and to investigate the cause of the persistent hypoglycemia. Extensive further investigation was performed without result.

Conclusion: After several conversations with psychologists, the patient admitted having manipulated the insulin pump resulting in auto-induced persistent and recurrent life-threatening hypoglycemia. Through camera monitoring, the team was able to confirm the manipulation.

Introduction: The clinical features of bi-allelic IGF1 defects are well established, i.e., severe growth failure and microcephaly, delayed psychomotor development, and sensorineural deafness. However, information on clinical and endocrine consequences of heterozygous IGF1 variants and treatment options is scarce. We aimed at extending the knowledge base of the clinical presentation and growth response to recombinant human growth hormone (rhGH) of patients carrying such variants.

Methods: Retrospective case series of patients with pathogenic heterozygous IGF1 variants.

Results: Nine patients from six families were included, harbouring five whole or partial gene deletions and one frameshift variant resulting in a premature stop codon (three de novo, one unknown inheritance). In the other two families, variants segregated with short stature. Mean (SD) birth length was -1.9 (1.3) SDS (n = 7), height -3.8 (0.6) SDS, head circumference -2.5 (0.6) SDS, serum IGF-I -1.9 (0.7) SDS, serum IGFBP-3 1.1 (0.4) SDS (n = 7), and GH peak range 5-31 μg/L (n = 4). Five patients showed feeding problems in infancy. Average height increased after 1 and 2 years of rhGH treatment by 0.8 SDS (range 0.3-1.3 SDS) and 1.3 SDS (range 0.5-2.0 SDS), respectively. Adult height in 2 patients was -2.8 and -1.3 SDS, which was, respectively, 1.3 and 2.9 SDS taller than predicted before start of treatment.

Conclusion: Haploinsufficiency of IGF1 causes a variable phenotype of prenatal and postnatal growth failure, microcephaly, feeding difficulties, low/low-normal serum IGF-I values in contrast to serum IGFBP-3 in the upper-normal range. Treatment with rhGH increased growth in the first 2 years of treatment, and in 2 patients adult height after treatment was higher than predicted at treatment initiation.