Growth and growth disorders in children and adolescents

Evolving growth hormone deficiency: proof of concept

Introduction

We present the evolution of GHD in adolescent males with persistent growth failure, in whom the diagnosis was established after a second GH stimulation test (GST).

Methods

We performed a retrospective chart review of children who presented for short stature (height less < 2SD for mean/mid-parental height) and/or growth failure (sustained growth velocity < 0 SD) to pediatric endocrinology at Mount Sinai Kravis Children's Hospital, New York and who had 2 GSTs. Data collected from electronic medical records were analyzed using SPSS v28.0.

Results

Of 53 patients included, 42 were males. Average GH peak on initial GST was 15.48 ± 4.92 ng/ml, at 10.07 ± 2.65 years, mean height -1.68 ± 0.56SD(28% had <2SD), IGF-1 -1.00 ± 0.88SD. After 2.23 ± 1.22 years, at 12.04 ± 2.41years, height SDs decreased to -1.82 ± 0.63SD and IGF-1 was -1.08 ± 0.84SD. At repeat GST, average GH peak was 7.59 ± 2.12 ng/dL, with 36% ≤7 ng/dl and 32% in puberty. 12 males reached adult height of 0.08 ± 0.69 SD with a mean height gain of 1.83 ± 0.56SD(p<0.005), IGF-1 of -1.15 ± 0.81SD after 4.64 ± 1.4 years of GH.

Conclusion

We offer evidence for Evolving Growth Hormone Deficiency (EGHD) through repeat GST in children with persistent growth slowdown, even with pubertal progression; emphasizing the need for careful longitudinal follow-up to make accurate diagnosis.

Mutational analysis of consanguineous families and their targeted therapy against dwarfism

Dwarfism is a medical term used to describe individuals with a height-vertex measurement that falls below two standard deviations (-2SD) or the third percentile for their gender and age. Normal development of growth is a complicated dynamic procedure that depends upon the coordination of different aspects involving diet, genetics, and biological aspects like hormones in equilibrium. Any severe or acute pathologic procedure may disturb the individual's normal rate of growth. In this research, we examined four (A-D) Pakistani consanguineous families that exhibited syndromic dwarfism, which was inherited in an autosomal recessive pattern. The genomic DNA of each family member was extracted by using phenol-chloroform and Kit methods. Whole Exome Sequencing (WES) of affected family members (IV-11, III-5, IV-4 and III-13) from each group was performed at the Department of Medical Genetics, University of Antwerp, Belgium. After filtering the exome data, the mutations in PPM1F, FGFR3, ERCC2, and PCNT genes were determined by Sanger sequencing of each gene by using specific primers. Afterward, FGFR3 was found to be a suitable drug target among all the mutations to treat achondroplasia also known as disproportionate dwarfism. BioSolveIT softwares were used to discover the lead active inhibitory molecule against FGFR3. This research will not only provide short knowledge to the concerned pediatricians, researchers, and family physicians for the preliminary assessment and management of the disorder but also provide a lead inhibitor for the treatment of disproportionate dwarfism.Communicated by Ramaswamy H. Sarma.

Evaluation of Adult Height in Patients with Non-Permanent Idiopathic GH Deficiency

Background: Several studies have evaluated the role of IGF-1 in the diagnosis of growth hormone deficiency (GHD). According to a recent study, an IGF-1 concentration of a −1.5 standard deviation score (SDS) appeared to be the best cut-off for distinguishing between children with GHD and normal children. This value should always be interpreted in conjunction with other clinical and biochemical parameters for the diagnosis of GHD, since both stimulation tests and IGF-1 assays have poor diagnostic accuracy by themselves. Our study was designed to evaluate the adult height (AH) in children with short stature and baseline IGF-1 concentration ≤ −1.5 SDS. Design: This retrospective analysis included 52 children and adolescents evaluated over the last 30 years for short stature and/or deceleration of the growth rate who underwent diagnostic procedures to evaluate a possible GHD. Only the patients who had baseline IGF-1 values ≤−1.5 SDS at the time of the first test were included in the study. Patients with genetic/organic GHD or underlying diseases were not included. Method: The case group consisted of 24 patients (13 boys and 11 girls) with non-permanent, idiopathic, and isolated GHD (peak GH < 10 μg/L after two provocative tests with arginine (Arg), insulin tolerance test (ITT), and clonidine (Clo), or <20 μg/L after GHRH + Arginine (GHRH+Arg); normal MRI; normal GH; and/or normal IGF-1 concentrations at near-AH). These patients were treated with GH (25–35 μg/kg/die) until near-AH. The control group consisted of 28 patients (23 boys and 5 girls) with idiopathic short stature (ISS, normal peak GH after provocative testing, no evidence of other causes for their shortness). Both groups had basal IGF-1 ≤−1.5 SDS. Results: AH and height gain in both groups were comparable. In the group of cases, mean IGF-1 SDS at the time of diagnosis was significantly lower than the levels found at the time of retesting. Conclusions: In this study, both treated patients with idiopathic GHD and untreated patients with ISS reached similar near-AHs (within target height) and showed similar increases in SDS for their height. Thus, the efficacy of treatment with rhGH in these patients may be questionable. This could be due to the fact that children with ISS are frequently misdiagnosed with GHD.

The Mediating Role of the Gut Microbiota in the Physical Growth of Children

Gut microbiota succession overlaps with intensive growth in infancy and early childhood. The multitude of functions performed by intestinal microbes, including participation in metabolic, hormonal, and immune pathways, makes the gut bacterial community an important player in cross-talk between intestinal processes and growth. Long-term disturbances in the colonization pattern may affect the growth trajectory, resulting in stunting or wasting. In this review, we summarize the evidence on the mediating role of gut microbiota in the mechanisms controlling the growth of children.

Growth Hormone Stimulation Testing: To Test or Not to Test? That Is One of the Questions

The evaluation of children with short stature includes monitoring over a prolonged period to establish a growth pattern as well as the exclusion of chronic medical conditions that affect growth. After a period of monitoring, evaluation, and screening, growth hormone stimulation testing is considered when the diagnosis of growth hormone deficiency (GHD) is entertained. Though flawed, growth hormone stimulation tests remain part of the comprehensive evaluation of growth and are essential for the diagnosis of growth hormone (GH) deficiency. Variables including testing length, growth hormone assay and diagnostic cut off affect results. Beyond the intrinsic issues of testing, results of GH stimulation testing can be influenced by patient characteristics. Various factors including age, gender, puberty, nutritional status and body weight modulate the secretion of GH.

Identifying and addressing disparities in the evaluation and treatment of children with growth hormone deficiency

Health disparities are a significant cause of concern globally and in the United States. Disparities have been additionally highlighted throughout the ongoing COVID-19 pandemic during which populations of color have been the most affected by the disease. Social determinants of health, race, ethnicity, and gender have all contributed to disparate outcomes and disparities spanning all age groups. Multiple socio-ecological factors contribute to disparities and different strategies have been proposed. The purpose of this paper is to provide an overview of disparities in pediatric treatment and outcomes, with a focus on children with endocrine disorders.

Pediatrics for Disability: A Comprehensive Approach to Children with Syndromic Psychomotor Delay

Intellectual disability is the impairment of cognitive, linguistic, motor and social skills that occurs in the pediatric age and is also described by the term "mental retardation". Intellectual disability occurs in 3-28 % of the general population due to a genetic cause, including chromosome aberrations. Among people with intellectual disabilities, the cause of the disability was identified as a single gene disorder in up to 12 %, multifactorial disorders in up to 4 %, and genetic disorders in up to 8.5 %. Children affected by a malformation syndrome associated with mental retardation or intellectual disability represent a care challenge for the pediatrician. A multidisciplinary team is essential to manage the patient, thereby controlling the complications of the syndrome and promoting the correct psychophysical development. This requires continuous follow-up of these children by the pediatrician, which is essential for both the clinical management of the syndrome and facilitating the social integration of these children.

Balanced assessment of growth disorders using clinical, endocrinological, and genetic approaches

Determining the pathogenesis of pediatric growth disorders is often challenging. In many cases, no pathogenesis is identified, and a designation of idiopathic short stature is used. The investigation of short stature requires a combination of clinical, endocrinological, and genetic evaluation. The techniques used are described, with equal importance being given to each of the 3 approaches. Clinical skills are essential to elicit an accurate history, family pedigree, and symptoms of body system dysfunction. Endocrine assessment requires hormonal determination for the diagnosis of hormone deficiency and initiation of successful replacement therapy. Genetic analysis has added a new dimension to the investigation of short stature and now uses next-generation sequencing with a candidate gene approach to confirm probable recognizable monogenic disorders and exome sequencing for complex phenotypes of unknown origin. Using the 3 approaches of clinical, endocrine, and genetic probes with equal status in the hierarchy of investigational variables provides the clinician with the highest chance of identifying the correct causative pathogenetic mechanism in a child presenting with short stature of unknown origin.

Digital technologies to improve the precision of paediatric growth disorder diagnosis and management

Paediatric disorders of impaired linear growth are challenging to manage, in part because of delays in the identification of pathological short stature and subsequent referral and diagnosis, the requirement for long-term therapy, and frequent poor adherence to treatment, notably with human growth hormone (hGH). Digital health technologies hold promise for improving outcomes in paediatric growth disorders by supporting personalisation of care, from diagnosis to treatment and follow up. The value of automated systems in monitoring linear growth in children has been demonstrated in Finland, with findings that such a system is more effective than a traditional manual system for early diagnosis of abnormal growth. Artificial intelligence has potential to resolve problems of variability that may occur during analysis of growth information, and augmented reality systems have been developed that aim to educate patients and caregivers about growth disorders and their treatment (such as injection techniques for hGH administration). Adherence to hGH treatment is often suboptimal, which negatively impacts the achievement of physical and psychological benefits of the treatment. Personalisation of adherence support necessitates capturing individual patient adherence data; the use of technology to assist with this is exemplified by the use of an electronic injection device, which shares real-time recordings of the timing, date and dose of hGH delivered to the patient with the clinician, via web-based software. The use of an electronic device is associated with high levels of adherence to hGH treatment and improved growth outcomes. It can be anticipated that future technological advances, coupled with continued 'human interventions' from healthcare providers, will further improve management of paediatric growth disorders.

Growth failure: 'idiopathic' only after a detailed diagnostic evaluation

The terms 'idiopathic short stature' (ISS) and 'small for gestational age' (SGA) were first used in the 1970s and 1980s. ISS described non-syndromic short children with undefined aetiology who did not have growth hormone (GH) deficiency, chromosomal defects, chronic illness, dysmorphic features or low birth weight. Despite originating in the pre-molecular era, ISS is still used as a diagnostic label today. The term 'SGA' was adopted by paediatric endocrinologists to describe children born with low birth weight and/or length, some of whom may experience lack of catch-up growth and present with short stature. GH treatment was approved by the FDA for short children born SGA in 2001, and by the EMA in 2003, and for the treatment of ISS in the US, but not Europe, in 2003. These approvals strengthened the terms 'SGA' and 'ISS' as clinical entities. While clinical and hormonal diagnostic techniques remain important, it is the emergence of genetic investigations that have led to numerous molecular discoveries in both ISS and SGA subjects. The primary message of this article is that the labels ISS and SGA are not definitive diagnoses. We propose that the three disciplines of clinical evaluation, hormonal investigation and genetic sequencing should have equal status in the hierarchy of short stature assessments and should complement each other to identify the true pathogenesis in poorly growing patients.

Short stature and growth hormone deficiency in a subset of patients with Potocki-Lupski syndrome: Expanding the phenotype of PTLS

Potocki-Lupski Syndrome (PTLS, MIM 610883), or duplication of chromosome 17p11.2, is a clinically recognizable condition characterized by infantile hypotonia, failure to thrive, developmental delay, intellectual disability, and congenital anomalies. Short stature, classified as greater than two standard deviations below the mean, has not previously been considered a major feature of PTLS. Retrospective chart review on a cohort of 37 individuals with PTLS was performed to investigate the etiology of short stature. Relevant data included anthropometric measurements, insulin growth factor-1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP-3), growth hormone (GH) stimulation testing, blood glucose levels, brain MRI, and bone age. Approximately 25% (9/37) of individuals with PTLS had short stature. Growth hormone deficiency (GHD) was definitively identified in two individuals. These two PTLS patients with growth hormone deficiency, as well as three others with short stature and no documented GHD, received growth hormone and obtained improvement in linear growth. One individual was identified to have pituitary abnormalities on MRI and had complications of hypoglycemia due to unrecognized GHD. Individuals with PTLS can benefit from undergoing evaluation for GHD should they present with short stature or hypoglycemia. Early identification of GHD could facilitate potential therapeutic benefit for individuals with PTLS, including linear growth, musculoskeletal, and in cases of hypoglycemia, potentially cognitive development as well.

Failure to Thrive in the Outpatient Clinic: A New Insight

Failure to thrive (FTT) is an abnormal growth pattern determined by inadequate nutrition. It is a common problem in children, representing 5% to 10% of patients seen in an outpatient setting. Many definitions have been proposed based on anthropometric deterioration; however, they show poor concordance. No single definition is sufficiently sensitive in identifying faltering growth whilst a combination of multiple criteria seems more accurate. In light of the recent redefinition of pediatric malnutrition as a disequilibrium between requirements and intakes of energy, and macro- and micronutrients, a wider conception of FTT as an unsatisfactory nutritional status related to poor growth and health is useful. Although the most severe problems of micronutrient malnutrition are found in developing countries, people of all regions of the world can be affected by micronutrient deficiencies (MNDs), a form of undernutrition with relevant effects on growth and health. Changes in diets and lifestyle, elimination diets, food insecurity, and food intake disorders create the conditions at risk of faltering growth and MNDs. This new insight integrates the "classical" anthropometric criteria for definition and treatment, in the aim of warranting both a regular increase in size and an overall adequate development and health status.

Peak Growth Hormone Response to Combined Stimulation Test in 315 Children and Correlations with Metabolic Parameters

BACKGROUND/AIMS

Studies are lacking regarding the timing of peak growth hormone (PGH) response. We aim to elucidate the timing of PGH response to arginine and levodopa (A-LD) and evaluate the influence of body mass index (BMI) and other metabolic parameters on PGH.

METHODS

During growth hormone (GH) stimulation testing (ST) with A-LD, serum GH was measured at baseline and every 30 min up to 180 min. The PGH cut-off was defined as &amp;#x3c;10 ng/mL. IGF-1, IGF BP3, BMI, and metabolic parameters were obtained in a fasting state at baseline.

RESULTS

In the 315 tested children, stimulated PGH levels occurred at or before 120 min in 97.8% and at 180 min in 2.2%. GH area under the curve (AUC) positively correlated with PGH in all patients and with IGF-1 in pubertal males and females. BMI negatively correlated with PGH in all subjects. GH AUC negatively correlated with HOMA-IR and total cholesterol.

CONCLUSION

We propose termination of the GH ST with A-LD at 120 min since omission of GH measurement at 180 min did not alter the diagnosis of GH deficiency based on a cut-off of &amp;#x3c; 10 ng/mL. BMI should be considered in the interpretation of GH ST with A-LD. The relationships between GH AUC and metabolic parameters need further study.

Factors associated with recovery from stunting among under-five children in two Nairobi informal settlements

Childhood stunting is a public health concern in many low-and-middle income countries, as it is associated with both short-term and long-term negative effects on child cognitive development, physical health, and schooling outcomes. There is paucity of studies on recovery from stunting among under five children in these countries. Most studies focused on the recovery much later in adolescence. We used longitudinal data from two Nairobi urban settlements to determine the incidence of recovery from stunting and understand the factors associated with post-stunting linear growth among under-five children. A total of 1,816 children were recruited between birth and 23 months and were followed-up until they reached five years. We first looked at the time to recover from stunting using event history analysis and Cox regression. Second, we used height-for-age z-score slope modelling to estimate the change in linear growth among children who were stunted. Finally, we fitted a linear regression model of the variation in HAZ on a second degree fractional polynomials in child’s age to identify the factors associated with post-stunting linear growth. The principal findings are: i) the incidence of recovery from stunting was 45% among stunted under-five children in the two settlements; ii) timely child immunization, age at stunting, mother’s parity and household socioeconomic status are important factors associated with time to recover from stunting within the first five years of life; and iii) child illness status and age at first stunting, mother’s parity and age have a strong influence on child post-stunting linear growth. Access to child health services and increased awareness among health professionals and child caregivers, would be critical in improving child growth outcomes in the study settings. Additionally, specific maternal and reproductive health interventions targeting young mothers in the slums may be needed to reduce adolescent and young mother’s vulnerability and improve their child health outcomes.

Analysing child linear growth trajectories among under-5 children in two Nairobi informal settlements

OBJECTIVE

We sought to identify factors associated with linear growth among under-5 children in two urban informal settlements in Nairobi.

DESIGN

We used longitudinal data for the period 2007-2012 from under-5 children recruited in the two sites between birth and 23 months and followed up until they reached 5 years of age. We fitted a generalized linear model on height-for-age Z-scores using the generalized estimating equations method to model linear growth trajectories among under-5 children. Known for its flexibility, the model provides strong parameter estimates and accounts for correlated observations on the same child.

SETTING

Two urban informal settlements in Nairobi, Kenya.ParticipantsUnder-5 children (n 1917) and their mothers (n 1679).

RESULTS

The findings show that child weight at birth, exclusive breast-feeding and immunization status were key determinants of linear growth among under-5 children. Additionally, maternal characteristics (mother's age, marital status) and household-level factors (socio-economic status, size of household) were significantly associated with child linear growth. There were biological differences in linear growth, as female children were more likely to grow faster than males. Finally, the model captured significant household-level effects to investigate further.

CONCLUSIONS

Findings from the study point to the need to improve the targeting of child health programmes directed at the urban poor population in Nairobi. Specific modifiable determinants of child linear growth, particularly child weight at birth, exclusive breast-feeding, immunization status and mother's background characteristics, should be considered when designing interventions aiming at addressing child health inequities in these settings.

Genetic Techniques in the Evaluation of Short Stature

Normal growth is a complex dynamic process dependent on the coordination of multiple factors including genetics, nutrition and hormones that are all working in balance. This chapter will review selected features of commonly utilized genetic techniques such as chromosomal analysis, microarray analysis, targeted gene screening and whole exome sequencing that are being used to identify genes influencing growth. As genetic technologies continue to improve and become more accessible many of these techniques will help to provide a better understanding of mechanisms underlying abnormal growth and will eventually lead to novel management approaches for abnormal growth.

Growth and growth hormone: An overview

Growth is a good indicator of a child's health. Growth disturbances, including short stature or growth failure, could be indications of illnesses such as chronic disease, nutritional deficits, celiac disease or hormonal abnormalities. Therefore, a careful assessment of the various requirements for normal growth needs to be done by history, physical examination, and screening laboratory tests. More details will be reviewed about the GH-IGF axis, its abnormalities with special emphasis on GH deficiency, its diagnosis and treatment. GH treatment indications in the US will be reviewed and a few only will be highlighted. They will include GH deficiency, as well as the treatment of children born SGA, including the results of a US study using FDA approved dose of 0.48mg/kg/week. GH deficiency in adults will also be briefly reviewed. Treatment of patients with SHOX deficiency will also be discussed. Possible side effects of GH treatment and the importance of monitoring safety will be highlighted.

Validation and ease of use of a new pen device for self-administration of recombinant human growth hormone: results from a two-center usability study

Close adherence to the recommended treatment regimen is important for the success of recombinant human growth hormone therapy, although nonadherence can be common. Ease of use and safety during use/storage are among several important factors in the design of a growth hormone injection device intended for long-term use. This study was performed to validate the usability and assess the ease of use of a new pen device (SurePal™) that has been developed to support daily administration of the recombinant human growth hormone product, Omnitrope® (somatropin). The primary objectives of the study were to assess if study participants, representing intended users of the pen in clinical practice, were able to perform an injection procedure into an injection pad effectively and safely and disassemble the pen without receiving a needlestick injury. A total of 106 participants (61 adults and 45 children/adolescents) were enrolled at two study centers (one in the US, one in Germany). Results for both primary usability tasks met the predefined acceptance criteria, with >85% of participants successfully performing each task. All of the other tasks/handling steps assessed were also successfully performed by most participants, with high success rates reflected in the high proportion of participants who classified each task as “very easy” or “easy”. After a second use of the device, 87%–97% of participants rated it as “very easy” or “easy” to use. In summary, the new pen device is safe and easy to use for both adults and children, and will help to support effective, long-term daily administration of the recombinant human growth hormone product, Omnitrope®.