Bringing the Pediatric Endocrine Spanish Speaking Community Together: First Virtual Pediatric Endocrine Meeting in Low- and Middle-Income Countries in Central and South America.

BACKGROUND: Pediatric endocrinology is a specialty that is struggling worldwide to maintain adequately trained professionals. Pediatric endocrine care in Central America and Caribbean countries is often performed by pediatricians or adult endocrinologists due to the limited number of pediatric endocrinologists. These health care providers are seldom members of endocrine societies and frequently lack formal training in the field. OBJECTIVE: In this study, we describe the scope of a virtual conference in pediatric endocrinology and diabetes targeted to low- and middle-income countries to provide equal opportunities for access to medical education for health care professionals. METHODS: The virtual conference was sponsored by the Pediatric Endocrine Society (North America), Asociación Costarricense de Endocrinología (previously, Asociación Nacional Pro Estudio de la Diabetes, Endocrinología y Metabolismo), and Asociacion Centroamericana y del Caribe de Endocrinologia Pediátrica. The conference was free to participants and comprised 23 sessions that were either synchronous with ability for real-time interactive sessions or asynchronous sessions, where content was available online to access at their convenience. Topics included idiopathic short stature, polycystic ovarian syndrome, diabetes mellitus, telemedicine, Turner syndrome, congenital adrenal hyperplasia, obesity, central precocious puberty, and subclinical hypothyroidism. The participants were asked to evaluate the conference after its completion with a questionnaire. RESULTS: A total of 8 speakers from Spain, Canada, Costa Rica, and the United States delivered the virtual event to 668 health care professionals from Guatemala, Venezuela, Dominican Republic, Costa Rica, Ecuador, Peru, Uruguay, Mexico, Honduras, Argentina, the United States, Bolivia, Chile, Panama, El Salvador, Nicaragua, Paraguay, Belize, Spain, and Colombia. Name, profession, and country were fully disclosed by 410 (61.4%) of the 668 health care professionals. The profession or level of training of participants were as follows: pediatric endocrinologists (n=129, 19.3%), pediatricians (n=116, 17.4%), general practitioners (n=77, 11.5%), adult endocrinologists (n=34, 5.1%), medical students (n=23, 3.4%), residents in various specialties (n=14, 2.1%), and others (n=17, 2.6%). A total of 23 sessions were offered, most of which were bilingual (Spanish and English). Feedback from the evaluation questionnaire indicated that the content of the conference was very relevant to the participants' professional practice. Additionally, the participants reported that they were very satisfied with the organization, the web-based platform, and the sessions of the conference. CONCLUSIONS: Lack of accessibility to the latest and cutting-edge medical education in pediatric endocrinology and diabetes for medical professionals from low- and middle-income countries can be overcome with a virtual conference. Online availability, low cost, and easy-to-use technology were well received from the participants, who were overall very satisfied by the quality and the relevance of the sessions to their professional practice.

Worldwide differences in childhood type 1 diabetes: The SWEET experience.

OBJECTIVE: To study worldwide differences in childhood diabetes, comparing relevant indicators among five regions within the SWEET initiative. SUBJECTS: We investigated 26 726 individuals with type 1 diabetes (T1D) from 54 centers in the European region; 7768 individuals from 30 centers in the Asia/Middle East/Africa region; 2642 people from five centers in Australia/New Zealand; 10 839 individuals from seven centers in North America, and 1114 patients from five centers in South America. METHODS: The SWEET database was analyzed based on the following inclusion criteria: T1D, time period 2015-2019, and age < 21 years, with analysis of the most recent documented year of therapy. For the statistical analysis, we used multivariable linear and logistic regression models to adjust for age (<6 years, 6- < 12 years, 12- < 18 years, 18- < 21 years), gender, and duration of diabetes (<2 years, 2- < 5 years, 5- < 10 years, ≥10 years). RESULTS: Adjusted HbA1c means ranged from 7.8% (95%-confidence interval: 7.6-8.1) in Europe to 9.5% (9.2-9.8) in Asia/Middle East/Africa. Mean daily insulin dose ranged from 0.8 units/kg in Europe (0.7-0.8) and Australia/New Zealand (0.6-0.9) to 1.0 unit/kg 0.9-1.1) in Asia/Middle East/Africa. Percentage of pump use was highest in North America (80.7% [79.8-81.6]) and lowest in South America (4.2% [3.2-5.6]). Significant differences between the five regions were also observed with regards to body mass index SD scores, frequency of blood glucose monitoring and presence of severe hypoglycaemia. CONCLUSIONS: We found significant heterogeneity in diabetes care and outcomes across the five regions. The aim of optimal care for each child remains a challenge.

A new approach to the diagnosis of short stature.

Growth is the task of children. We review the normal process of linear growth from the fetus through adolescence and note that growth is the result of age- and gender-dependent interactions among key genetic, environmental, dietary, socioeconomic, developmental, behavioral, nutritional, metabolic, biochemical, and hormonal factors. We then define the wide range of normative data at each stage of growth and note that a pattern within this range is generally indicative of good general health and that growth significantly slower than this range may lead to growth faltering and subsequent short stature. Although not often emphasized, we detail how to properly measure infants and children because height velocity is usually determined from two height measurements (both relatively large values) to calculate the actual height velocity (a relatively much smaller number in comparison). Traditionally the physiology of growth has been taught from an endocrine-centric point-of-view. Here we review the hypothalamic-pituitary-end organ axes for the GH/IGF-1 and gonadal steroid hormones (hypothalamic-pituitary-gonadal axis), both during "mini"-puberty as well as at puberty. However, over the past few decades much more emphasis has been placed on the growth plate and its many interactions with the endocrine system but also with its own intrinsic physiology and gene mutations. These latter, whether individually (large effect size) or in combination with many others including endocrine system-based, may account in toto for meaningful differences in adult height. The clinical assessment of children with short stature includes medical, social and family history, physical exam and importantly proper interpretation of the growth curve. This analysis should lead to judicious use of screening laboratory and imaging tests depending on the pre-test probability (Bayesian inference) of a particular diagnosis in that child. In particular for those with no pathological features in the history and physical exam and a low, but normal height velocity, may lead only to a bone age exam and reevaluation (re-measurement), perhaps 6 months later. he next step depends on the comfort level of the primary care physician, the patient, and the parent; that is, whether to continue with the evaluation with more directed, more sophisticated testing, again based on Bayesian inference or to seek consultation with a subspecialist pediatrician based on the data obtained. This is not necessarily an endocrinologist. The newest area and the one most in flux is the role for genetic testing, given that growth is a complex process with large effect size for single genes but smaller effect sizes for multiple other genes which in the aggregate may be relevant to attained adult height. Genetics is a discipline that is rapidly changing, especially as the cost of exome or whole gene sequencing diminishes sharply. Within a decade it is quite likely that a genetic approach to the evaluation of children with short stature will become the standard, truncating the diagnostic odyssey and be cost effective as fewer biochemical and imaging studies are required to make a proper diagnosis.

Association of diabetic ketoacidosis and HbA1c at onset with year-three HbA1c in children and adolescents with type 1 diabetes: Data from the International SWEET Registry.

OBJECTIVE: To establish whether diabetic ketoacidosis (DKA) or HbA1c at onset is associated with year-three HbA1c in children with type 1 diabetes (T1D). METHODS: Children with T1D from the SWEET registry, diagnosed <18 years, with documented clinical presentation, HbA1c at onset and follow-up were included. Participants were categorized according to T1D onset: (a) DKA (DKA with coma, DKA without coma, no DKA); (b) HbA1c at onset (low [<10%], medium [10 to <12%], high [≥12%]). To adjust for demographics, linear regression was applied with interaction terms for DKA and HbA1c at onset groups (adjusted means with 95% CI). Association between year-three HbA1c and both HbA1c and presentation at onset was analyzed (Vuong test). RESULTS: Among 1420 children (54% males; median age at onset 9.1 years [Q1;Q3: 5.8;12.2]), 6% of children experienced DKA with coma, 37% DKA without coma, and 57% no DKA. Year-three HbA1c was lower in the low compared to high HbA1c at onset group, both in the DKA without coma (7.1% [6.8;7.4] vs 7.6% [7.5;7.8], P = .03) and in the no DKA group (7.4% [7.2;7.5] vs 7.8% [7.6;7.9], P = .01), without differences between low and medium HbA1c at onset groups. Year-three HbA1c did not differ among HbA1c at onset groups in the DKA with coma group. HbA1c at onset as an explanatory variable was more closely associated with year-three HbA1c compared to presentation at onset groups (P = .02). CONCLUSIONS: Year-three HbA1c is more closely related to HbA1c than to DKA at onset; earlier hyperglycemia detection might be crucial to improving year-three HbA1c.

Treatment of growth hormone deficiency in children, adolescents and at the transitional age.

Recombinant human growth hormone (rhGH) has been available since 1985. Before 1985 growth hormone (GH) was extracted from cadaveric pituitary glands, but this was stopped in most countries that year, following the recognition that it could transmit Creutzfeldt-Jacob disease. The primary goal of rhGH treatment in GHD patients is to normalize height during childhood and adolescence and attain an adult height within the normal range and within the target height range (genetic potential). Genome-wide association studies have been used increasingly to study the genetic influence on height. There is a wide response to rhGH therapy, likely due to compliance issues, severity of GH deficiency and patient's sensitivity to rhGH. While some pediatric endocrinologists will use a fixed dose of rhGH, most will use an auxology-based dosing approach. This will involve starting at the lower end of the dose range and then titrating upwards based on the patient's response to therapy with measurement of IGF-1 concentrations to ensure that the patient is not over treated or undertreated. Although treatment of children with GHD with rhGH has generally been safe, careful follow-up by a pediatric endocrinologist in partnership with the pediatrician or primary care physician is recommended. The aim of this paper is to review the strategies and recommendations for treatment of GHD in children and patients in the transition to adult care.

Contribution of SWEET to improve paediatric diabetes care in developing countries.

Diabetes affects many children living in developing countries. Through an informal survey, five SWEET (Better control in Pediatric and Adolescent diabeteS: Working to crEate CEnTers of Reference) centers from developing countries (Mali, Costa Rica, Argentina and two from India) share their perspective on caring for children with diabetes. Each center provides a description of the population of children with diabetes they serve, the organization of care, and the challenges encountered on a daily basis in the provision of this care. In the second part, we summarize the anticipated benefits and challenges associated with participation in SWEET. This resulting article is a testimony of the reality of managing diabetes by dynamic teams striving to achieve recommended standards of care for pediatric diabetes in an environment with limited resources.

Endocrine Responses to Exercise in the Developing Child and Adolescent.

The impact of exercise training on the neuroendocrine control of the pituitary in the developing child is complex and the exact mechanisms are not fully understood. Multiple determinants influence adaptive hypothalamic-pituitary secretory responses to physical stress, namely, training intensity and duration, nutrition and energy balance, gender, age, sex, and sexual maturation status. The increase in growth hormone (GH) in response to acute exercise is dependent on pubertal status; children in more advanced pubertal stages respond with larger peak GH concentrations compared to those in earlier stages. The adolescent female athlete is more prone to menstrual disorders than the more mature athlete, and recent data suggest that athletes may be able to reverse menstrual disorders by increasing their dietary energy intake without decreasing their exercise levels. The thyroid changes observed are of minor impact, practically reflecting the relative negative energy balance during strenuous exercise. Studies that evaluated changes in cortisol secretion during aerobic exercise in children and adolescents show either an increase or no change in response to the exercise bout. Recent research showed that physical activity is an important contributor to bone strength prior to adolescence and increasing levels of physical activity during childhood likely enhance optimal bone strength.

Oblique facial clefts in Johanson-Blizzard syndrome.

Johanson-Blizzard syndrome (JBS) is considered as an infrequent, but clinically easily recognizable autosomal recessive entity by the pathognomonic combination of congenital exocrine pancreatic insufficiency and hypoplastic alae nasi, in addition to other distinctive findings such as scalp defects, hypothyroidism, and rectourogenital malformations. There are few reports of patients with JBS in association with facial clefting, referring all to types 2 to 6 of Tessier's classification that can be characterized properly as oblique facial clefts (OFCs). We describe the clinical aspects in four patients with JBS and extensive OFCs. In all of them, the diagnosis of JBS was confirmed by the demonstration of homozygous or compound-heterozygous mutations in the UBR1 gene. Additionally, we review three previously reported cases of JBS with OFCs. Taking into account a number of approximately 100 individuals affected by JBS that have been published in the literature we estimate that the frequency of OFCs in JBS is between 5% and 10%. This report emphasizes that extensive OFCs may be the severe end of the spectrum of facial malformations occurring in JBS. No obvious genotype phenotype correlation could be identified within this cohort. Thus, UBR1 should be included within the list of contributory genes of OFCs, although the exact mechanism remains unknown. © 2016 Wiley Periodicals, Inc.

Mutations in the human UBR1 gene and the associated phenotypic spectrum.

Johanson-Blizzard syndrome (JBS) is a rare, autosomal recessive disorder characterized by exocrine pancreatic insufficiency, typical facial features, dental anomalies, hypothyroidism, sensorineural hearing loss, scalp defects, urogenital and anorectal anomalies, short stature, and cognitive impairment of variable degree. This syndrome is caused by a defect of the E3 ubiquitin ligase UBR1, which is part of the proteolytic N-end rule pathway. Herein, we review previously reported (n = 29) and a total of 31 novel UBR1 mutations in relation to the associated phenotype in patients from 50 unrelated families. Mutation types include nonsense, frameshift, splice site, missense, and small in-frame deletions consistent with the hypothesis that loss of UBR1 protein function is the molecular basis of JBS. There is an association of missense mutations and small in-frame deletions with milder physical abnormalities and a normal intellectual capacity, thus suggesting that at least some of these may represent hypomorphic UBR1 alleles. The review of clinical data of a large number of molecularly confirmed JBS cases allows us to define minimal clinical criteria for the diagnosis of JBS. For all previously reported and novel UBR1 mutations together with their clinical data, a mutation database has been established at LOVD.

Traumatic brain injury: endocrine consequences in children and adults.

Traumatic brain injury (TBI) is a common cause of death and disability in young adults with consequences ranging from physical disabilities to long-term cognitive, behavioral, psychological and social defects. Recent data suggest that pituitary hormone deficiency is not infrequent among TBI survivors; the prevalence of reported hypopituitarism following TBI varies widely among published studies. The most common cause of TBI is motor vehicle accidents, including pedestrian-car and bicycle car encounters, falls, child abuse, violence and sports injuries. Prevalence of hypopituitarism, from total to isolated pituitary deficiency, ranges from 5 to 90 %. The time interval between TBI and pituitary function evaluation is one of the major factors responsible for variations in the prevalence of hypopituitarism reported. Endocrine dysfunction after TBI in children and adolescents is common. Adolescence is a time of growth, freedom and adjustment, consequently TBI is also common in this group. Sports-related TBI is an important public health concern, but many cases are unrecognized and unreported. Sports that are associated with an increased risk of TBI include those involving contact and/or collisions such as boxing, football, soccer, ice hockey, rugby, and the martial arts, as well as high velocity sports such as cycling, motor racing, equestrian sports, skiing and roller skating. The aim of this paper is to summarize the best evidence of TBI as a cause of pituitary deficiency in children and adults.

Current indications for growth hormone therapy for children and adolescents.

Growth hormone (GH) therapy has been appropriate for severely GH-deficient children and adolescents since the 1960s. Use for other conditions for which short stature was a component could not be seriously considered because of the small supply of human pituitary-derived hormone. That state changed remarkably in the mid-1980s because of Creutzfeldt-Jakob disease associated with human pituitary tissue-derived hGH and the development of a (nearly) unlimited supply of recombinant, 22 kDa (r)hGH. The latter permitted all GH-deficient children to have access to treatment and one could design trials using rhGH to increase adult height in infants, children and adolescents with causes of short stature other than GH deficiency, as well as trials in adult GH-deficient men and women. Approved indications (US Food and Drug Administration) include: GH deficiency, chronic kidney disease, Turner syndrome, small-for-gestational age with failure to catch up to the normal height percentiles, Prader-Willi syndrome, idiopathic short stature, SHOX gene haploinsufficiency and Noonan syndrome (current to October 2008). The most common efficacy outcome in children is an increase in height velocity, although rhGH may prevent hypoglycemia in some infants with congenital hypopituitarism and increase the lean/fat ratio in most children - especially those with severe GH deficiency or Prader-Willi syndrome. Doses for adults, which affect body composition and health-related quality of life, are much lower than those for children, per kilogram of lean body mass. The safety profile is quite favorable with a small, but significant, incidence of raised intracranial pressure, scoliosis, muscle and joint discomfort, including slipped capital femoral epiphysis. The approval of rhGH therapy for short, non-GH-deficient children has validated the notion of GH sensitivity, which gives the opportunity to some children with significant short stature, but with normal stimulated GH test results, to benefit from rhGH therapy and perhaps attain an adult height within the normal range and appropriate for their mid-parental target height (genetic potential).

Recombinant human insulin-like growth factor-I therapy for children with growth disorders.

Until recently, the only possible therapy available for treatment of children with significant short stature was recombinant human growth hormone (rhGH). However, recombinant human insulin-like growth factor-I (rhIGF-I) has now become commercially available as a therapeutic option to treat children of short stature caused by severe primary IGF-I deficiency, defined as: height standard deviation score (SDS) less than or equal to -3.0, basal IGF-I SDS less than or equal to -3.0, and normal or elevated levels of GH. Published data demonstrate that rhIGF-I therapy in patients with primary IGF-I deficiency accelerates growth significantly during the first year of treatment, but progressive attenuation is likely in subsequent years. The growth response to rhIGF-I is neither as intense nor as well sustained as the growth response to rhGH among children with GH deficiency. Despite increasing interest in the possibility for broader use of rhIGF-I for growth promotion, especially in children with idiopathic short stature (ISS), it is necessary to wait for studies assessing the efficacy and safety of rhIGF-I therapy in this condition. In this particular population (ISS patients), the combination of rhIGF-I and rhGH, compared with either hormone used alone, may have theoretical advantages. Hypoglycemia has been the most common side effect reported with use of rhIGF-I and is reasonably controlled with adequate food intake. Most of the other (long-term) adverse effects appear to be related to hyperstimulation of lymphoid tissue growth. Little is known about the long-term effects of IGF-I therapy in growing children, but caution and long-term, controlled, prospective trials of rhIGF-I-treated children and adolescents are needed.

Clinical and molecular profile of a new series of patients with immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome: inconsistent correlation between forkhead box protein 3 expression and disease severity.

BACKGROUND: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an autoimmune genetic disorder caused by mutation of the forkhead box protein 3 gene (FOXP3), a key regulator of immune tolerance. OBJECTIVE: We sought to provide clinical and molecular indicators that facilitate the understanding and diagnosis of IPEX syndrome. METHODS: In 14 unrelated affected male subjects who were given diagnoses of IPEX syndrome based on FOXP3 gene sequencing, we determined whether particular FOXP3 mutations affected FOXP3 protein expression and correlated the molecular and clinical data. RESULTS: Molecular analysis of FOXP3 in the 14 subjects revealed 13 missense and splice-site mutations, including 7 novel mutations. Enteropathy, generally associated with endocrinopathy and eczema, was reported in all patients, particularly in those carrying mutations within FOXP3 functional domains or mutations that altered protein expression. However, similar genotypes did not always result in similar phenotypes in terms of disease presentation and severity. In addition, FOXP3 protein expression did not correlate with disease severity. CONCLUSION: Severe autoimmune enteropathy, which is often associated with increased IgE levels and eosinophilia, is the most prominent early manifestation of IPEX syndrome. Nevertheless, the disease course is variable and somewhat unpredictable. Therefore genetic analysis of FOXP3 should always be performed to ensure an accurate diagnosis, and FOXP3 protein expression analysis should not be the only diagnostic tool for IPEX syndrome.

Growth hormone deficiency in children.

The foundation for the diagnosis of growth hormone (GH) deficiency in childhood must be auxology, that is, the comparison of the child's growth pattern to that of established norms for gender and ethnicity. It is only in those growing considerably more slowly than average that testing for GHD makes sense. Assessment of laboratory tests, whether static, for example, the measurement of growth factors or their binding proteins, or dynamic, for example, secretagogue-stimulated GH secretion is confirmatory. One must be cognizant of the assay used to determine GH, for there may be a 3-fold difference in the concentration of GH among commercially-available assays. Controversy still exists concerning the measurement of spontaneous GH release and whether sex-steroid priming is appropriate in prepubertal children. Imaging analysis may prove helpful in some children with congenital GHD or to detect a space-occupying lesion in the area of the hypothalamus and pituitary. The final diagnosis is based on multiple parameters and occasionally on a therapeutic trial of GH therapy to determine if there is a significant acceleration of growth velocity.

Male pubertal development and the role of androgen therapy.

In boys, the hormonal changes that accompany normal puberty are well defined, as are the physical signs of pubertal development and the kinetics of the growth spurt. Most androgens are derived from the testes, although adrenal androgens may also contribute; testosterone can also be aromatized to estrogen to exert important effects during puberty. Androgens, but especially their conversion to estrogens by aromatase, have a major role in the dramatic changes in linear growth, secondary sexual characteristics, and changes to bone, muscle and fat distribution that occur during puberty. Androgen therapy for delayed puberty should permit full normal pubertal development and thereby also address some of the associated psychosocial problems. Adolescent boys with conditions of permanent hypogonadism (hypogonadotropic or hypergonadotropic) or transient hypogonadotropic hypogonadism (constitutional delay of growth and puberty) can benefit from testosterone therapy. Long-term testosterone therapy should be given for hypothalamic or pituitary gonadotropin deficiency, or for primary hypogonadism such as for adolescents with Klinefelter syndrome, if endogenous testosterone levels drop or levels of luteinizing hormone rise. Intramuscular administration every few weeks is effective, but newer cutaneous forms, for example, gels or patches, also show promise in permitting adolescent males to reach adult body composition.

Somatotropic and gonadotropic axes linkages in infancy, childhood, and the puberty-adult transition.

Integrative neuroendocrine control of the gonadotropic and somatotropic axes in childhood, puberty, and young adulthood proceeds via multiple convergent and divergent pathways in the human and experimental animal. Emerging ensemble concepts are required to embody independent, parallel, and interacting mechanisms that subserve physiological adaptations and pathological disruption of reproduction and growth. Significant advances in systems biology will be needed to address these challenges.

Individualized therapy for growth hormone deficiency.

The use of human growth hormone to treat children with short stature resulting from growth hormone deficiency or insufficiency has now accrued over 40 years of clinical experience with a satisfactory safety and efficacy record. Growth hormone deficiency is the primary indication for growth hormone treatment in childhood. It is basically a clinical diagnosis, based upon auxologic features, and confirmed by biochemical testing. For assurance of compliance, dosing and, perhaps, safety considerations, a dosing algorithm based upon insulin-like growth factor-I response seems to be appropriate. Current data suggest that such algorithms reflect the true growth hormone needs of a patient, and allow optimization of growth hormone treatment. For patients who display a suboptimal growth response or in whom the insulin growth factor levels remain low with assurance of adherence to the injection schedule, it is reasonable to increase the growth hormone dose. The availability of recombinant human insulin-like growth factor-I treatment may provide an alternative for massively increasing the dose of growth hormone. Dose reductions should be considered for patients with serum insulin-like growth factor-I levels substantially above the normal range.

Endocrine control of body composition in infancy, childhood, and puberty.

Body composition exhibits marked variations across the early human lifetime. The precise physiological mechanisms that drive such developmental adaptations are difficult to establish. This clinical challenge reflects an array of potentially confounding factors, such as marked intersubject differences in tissue compartments; the incremental nature of longitudinal intrasubject variations in body composition; technical limitations in quantitating the unobserved mass of mineral, fat, water, and muscle ad seriatim; and the multifold contributions of genetic, dietary, environmental, hormonal, nutritional, and behavioral signals to physical and sexual maturation. From an endocrine perspective (reviewed here), gonadal sex steroids and GH/IGF-I constitute prime determinants of evolving body composition. The present critical review examines hormonal regulation of body composition in infancy, childhood, and puberty.