Progression from isolated growth hormone deficiency to combined pituitary hormone deficiency

Diagnosing and treating anterior pituitary hormone deficiency in pediatric patients

Hypopituitarism, or the failure to secrete hormones produced by the anterior pituitary (adenohypophysis) and/or to release hormones from the posterior pituitary (neurohypophysis), can be congenital or acquired. When more than one pituitary hormone axis is impaired, the condition is known as combined pituitary hormone deficiency (CPHD). The deficiency may be primarily due to a hypothalamic or to a pituitary disorder, or concomitantly both, and has a negative impact on target organ function. This review focuses on the pathophysiology, diagnosis and management of anterior pituitary hormone deficiency in the pediatric age. Congenital hypopituitarism is generally due to genetic disorders and requires early medical attention. Exposure to toxicants or intrauterine infections should also be considered as potential etiologies. The molecular mechanisms underlying the fetal development of the hypothalamus and the pituitary are well characterized, and variants in the genes involved therein may explain the pathophysiology of congenital hypopituitarism: mutations in the genes expressed in the earliest stages are usually associated with syndromic forms whereas variants in genes involved in later stages of pituitary development result in non-syndromic forms with more specific hormone deficiencies. Tumors or lesions of the (peri)sellar region, cranial radiation therapy, traumatic brain injury and, more rarely, other inflammatory or infectious lesions represent the etiologies of acquired hypopituitarism. Hormone replacement is the general strategy, with critical periods of postnatal life requiring specific attention.

Clinical Characteristics of Children with Combined Pituitary Hormone Deficiency and the Effects of Growth Hormone Treatment

AIM

We aimed to describe the clinical characteristics of patients with congenital combined pituitary hormone deficiency (CPHD) and evaluate the first-year growth responses of individuals with CPHD and isolated growth hormone deficiency (IGHD) in order to establish the influence of other hormone deficiencies on growth response.

PATIENTS AND METHODS

This retrospective study was conducted in four tertiary care centers in Turkey. The records of patients diagnosed with CPHD (n=39) and severe IGHD (n=50) were collected. Cases with acquired lesions or chronic diseases were not included in the study. Data are presented as median (interquartile range).

RESULTS

Among 39 patients (13 females; 33%) with a diagnosis of CPHD, the majority of patients (64%) presented initially with combined deficits at baseline examination, whereas isolated deficiencies (36%) were less prevalent. Among all patients with GH deficiency, TSH, ACTH, FSH/LH, and ADH deficiencies were present in 94%, 74%, 44%, and 9% of patients, respectively. Patients with CPHD were diagnosed at a younger age (4.9 (8.4) vs. 11.6 (4.1), p<0.001, respectively) and had lower peak GH concentrations (0.4 (1.8) vs. 3.7 (2.9), p<0.001, respectively) than patients with IGHD. Patients with IGHD and CPHD had similar first-year growth responses (Δheight SD score of 0.55 (0.63) vs. 0.76 (0.71), respectively, p=0.45).

CONCLUSIONS

We established the nature and timing of numerous hormonal deficits emerging over time. We also identified that the existence of CPHD did not hinder growth response.

Deep phenotyping of the neuroimaging and skeletal features in KBG syndrome: a study of 53 patients and review of the literature

BACKGROUND

KBG syndrome is caused by haploinsufficiency of ANKRD11 and is characterised by macrodontia of upper central incisors, distinctive facial features, short stature, skeletal anomalies, developmental delay, brain malformations and seizures. The central nervous system (CNS) and skeletal features remain poorly defined.

METHODS

CNS and/or skeletal imaging were collected from molecularly confirmed individuals with KBG syndrome through an international network. We evaluated the original imaging and compared our results with data in the literature.

RESULTS

We identified 53 individuals, 44 with CNS and 40 with skeletal imaging. Common CNS findings included incomplete hippocampal inversion and posterior fossa malformations; these were significantly more common than previously reported (63.4% and 65.9% vs 1.1% and 24.7%, respectively). Additional features included patulous internal auditory canal, never described before in KBG syndrome, and the recurrence of ventriculomegaly, encephalic cysts, empty sella and low-lying conus medullaris. We found no correlation between these structural anomalies and epilepsy or intellectual disability. Prevalent skeletal findings comprised abnormalities of the spine including scoliosis, coccygeal anomalies and cervical ribs. Hand X-rays revealed frequent abnormalities of carpal bone morphology and maturation, including a greater delay in ossification compared with metacarpal/phalanx bones.

CONCLUSION

This cohort enabled us to describe the prevalence of very heterogeneous neuroradiological and skeletal anomalies in KBG syndrome. Knowledge of the spectrum of such anomalies will aid diagnostic accuracy, improve patient care and provide a reference for future research on the effects of ANKRD11 variants in skeletal and brain development.

Diagnosis and Incidence of Congenital Combined Pituitary Hormone Deficiency in Denmark-A National Observational Study

CONTEXT

Congenital combined pituitary hormone deficiency (cCPHD) is the loss of ≥2 pituitary hormones caused by congenital factors.

OBJECTIVE

We aimed to estimate the national incidence of cCPHD diagnosed before age 18 years and in subgroups.

METHODS

Patients with cCPHD were identified in the Danish National Patient Registry and Danish hospital registries in the period 1996-2020. Hospital files were reviewed and incidences calculated using background population data. Incidence was the main outcome measure.

RESULTS

We identified 128 patients with cCPHD; 88 (68.8%) were males. The median (range) age at diagnosis was 6.2 (0.01-19.0) years. The median (25th;75th percentile) number of hormone deficiencies at diagnosis was 3 (3; 4) at <1 year vs 2 (2; 2) at 1-17 years, P < .0001. Abnormal pituitary magnetic resonance imaging findings were seen in 70.3% (83/118). For those born in Denmark aged <18 years at diagnosis (n = 116/128) the estimated national incidence (95% CI) of cCPHD was 10.34 (7.79-13.72) per 100 000 births, with an annual incidence rate of 5.74 (4.33-7.62) per million. In subgroup analysis (diagnosis <1 vs 1-17 years), the incidence was highest in the 1-17 years subgroup, 7.97 (5.77-11.00) vs 1.98 (1.39-2.84) per 100 000 births, whereas the annual incidence rate was highest at <1 year, 19.8 (13.9-28.4) vs 4.69 (3.39-6.47) per million births.

CONCLUSION

cCPHD had the highest incidence rate and the most hormone deficiencies in those diagnosed at <1 year. The incidence was highest in the 1-17 years age group, underscoring the need for multiple pituitary hormone investigations throughout childhood and adolescence in children with only 1 hormone deficiency.

Identification of genetic variants and phenotypic characterization of a large cohort of patients with congenital hypopituitarism and related disorders

PURPOSE

Congenital hypopituitarism (CH) disorders are phenotypically variable. Variants in multiple genes are associated with these disorders, with variable penetrance and inheritance.

METHODS

We screened a large cohort (N = 1765) of patients with or at risk of CH using Sanger sequencing, selected according to phenotype, and conducted next-generation sequencing (NGS) in 51 families within our cohort. We report the clinical, hormonal, and neuroradiological phenotypes of patients with variants in known genes associated with CH.

RESULTS

We identified variants in 178 patients: GH1/GHRHR (51 patients of 414 screened), PROP1 (17 of 253), POU1F1 (15 of 139), SOX2 (13 of 59), GLI2 (7 of 106), LHX3/LHX4 (8 of 110), HESX1 (8 of 724), SOX3 (9 of 354), OTX2 (5 of 59), SHH (2 of 64), and TCF7L1, KAL1, FGFR1, and FGF8 (2 of 585, respectively). NGS identified 26 novel variants in 35 patients (from 24 families). Magnetic resonance imaging showed prevalent hypothalamo-pituitary abnormalities, present in all patients with PROP1, GLI2, SOX3, HESX1, OTX2, LHX3, and LHX4 variants. Normal hypothalamo-pituitary anatomy was reported in 24 of 121, predominantly those with GH1, GHRHR, POU1F1, and SOX2 variants.

CONCLUSION

We identified variants in 10% (178 of 1765) of our CH cohort. NGS has revolutionized variant identification, and careful phenotypic patient characterization has improved our understanding of CH. We have constructed a flow chart to guide genetic analysis in these patients, which will evolve upon novel gene discoveries.

Isolated anterior pituitary dysfunction in adulthood

Hypopituitarism is defined as a complete or partial deficiency in one or more pituitary hormones. Anterior hypopituitarism includes secondary adrenal insufficiency, central hypothyroidism, hypogonadotropic hypogonadism, growth hormone deficiency and prolactin deficiency. Patients with hypopituitarism suffer from an increased disability and sick days, resulting in lower health status, higher cost of care and an increased mortality. In particular during adulthood, isolated pituitary deficits are not an uncommon finding; their clinical picture is represented by vague symptoms and unclear signs, which can be difficult to properly diagnose. This often becomes a challenge for the physician. Aim of this narrative review is to analyse, for each anterior pituitary deficit, the main related etiologies, the characteristic signs and symptoms, how to properly diagnose them (suggesting an easy and reproducible step-based approach), and eventually the treatment. In adulthood, the vast majority of isolated pituitary deficits are due to pituitary tumours, head trauma, pituitary surgery and brain radiotherapy. Immune-related dysfunctions represent a growing cause of isolated pituitary deficiencies, above all secondary to use of oncological drugs such as immune checkpoint inhibitors. The diagnosis of isolated pituitary deficiencies should be based on baseline hormonal assessments and/or dynamic tests. Establishing a proper diagnosis can be quite challenging: in fact, even if the diagnostic methods are becoming increasingly refined, a considerable proportion of isolated pituitary deficits still remains without a certain cause. While isolated ACTH and TSH deficiencies always require a prompt replacement treatment, gonadal replacement therapy requires a benefit-risk evaluation based on the presence of comorbidities, age and gender of the patient; finally, the need of growth hormone replacement therapies is still a matter of debate. On the other side, prolactin replacement therapy is still not available. In conclusion, our purpose is to offer a broad evaluation from causes to therapies of isolated anterior pituitary deficits in adulthood. This review will also include the evaluation of uncommon symptoms and main etiologies, the elements of suspicion of a genetic cause and protocols for diagnosis, follow-up and treatment.

Normal or elevated prolactin is a good indicator to show pituitary stalk interruption syndrome in patients with multiple pituitary hormone deficiency

OBJECTIVES

To determine the importance of serum prolactin (PRL) in the detection of pituitary stalk interruption syndrome (PSIS) in children with multiple pituitary hormone deficiency (MPHD). We hypothesized that PRL elevation might be a diagnostic indicator of pituitary stalk pathologies.

METHODS

Clinical, radiological, and laboratory features of the 50 cases of MPHD were studied.

RESULTS

The median age at presentation of the 50 cases (52%, n=26 were female) was 6.61 (0.02-18.9) years. PSIS was detected in 60% (n=30), pituitary hypoplasia in 32% (n=16), partial empty sella in 6% (n=3), and only 2% (n=1) was reported as normal. Out of 50 patients, 21.3% (n=10) were hypoprolactinemic, 44.7% (n=19) were normoprolactinemic, and 34% (n=16) were hyperprolactinemic. The median PRL value was 27.85 (4.21-130) ng/mL in patients with PSIS and 5.57 (0-41.8) ng/mL in patients without PSIS. Additional hormone deficiencies, especially ACTH and LH were detected in follow-up.

CONCLUSIONS

Patients with normal or high prolactin levels deserve special attention regarding the possibility of PSIS. Furthermore, we emphasize the importance of regular follow-up and monitoring for multiple pituitary hormone deficiencies in all patients with a single pituitary hormone deficiency.

Approach to the Patient: Management of Pituitary Hormone Replacement Through Transition

Hypopituitarism in childhood is a rare, complex disorder that can present with highly variable phenotypes, which may continue into adult life. Pituitary deficits can evolve over time, with unpredictable patterns resulting in significant morbidity and mortality. Hypopituitarism and hypothalamic dysfunction may be associated with challenging comorbidities such as obesity, learning difficulties, behavioral issues, sleep disturbance, and visual impairment. Transition is the purposeful planned movement of adolescents and young adults with chronic conditions from child-centered to adult-oriented health care systems with a shift from parent- to patient-focused care. To achieve effective transition within a health care setting, the inherent challenges involved in the evolution from a dependent child to an independent adult must be recognized. Transition is a critical time medically for patients with hypopituitarism. Complex issues with respect to puberty, attainment of optimal stature, adherence to treatment, and acceptance of the need for life-sustaining medications need to be addressed. For health care professionals, transition is an opportunity for reassessment of the pituitary deficits and the need for lifelong replacement therapies, often against a background of complex psychological issues. We present 4 illustrative cases of hypopituitarism of differing etiologies with diverse clinical presentations. Diagnostic and management processes from clinical presentation to young adulthood are discussed, with a particular focus on needs and outcomes through transition.

High-throughput splicing assays identify missense and silent splice-disruptive POU1F1 variants underlying pituitary hormone deficiency

Pituitary hormone deficiency occurs in ∼1:4,000 live births. Approximately 3% of the cases are due to mutations in the alpha isoform of POU1F1, a pituitary-specific transcriptional activator. We found four separate heterozygous missense variants in unrelated individuals with hypopituitarism that were predicted to affect a minor isoform, POU1F1 beta, which can act as a transcriptional repressor. These variants retain repressor activity, but they shift splicing to favor the expression of the beta isoform, resulting in dominant-negative loss of function. Using a high-throughput splicing reporter assay, we tested 1,070 single-nucleotide variants in POU1F1. We identified 96 splice-disruptive variants, including 14 synonymous variants. In separate cohorts, we found two additional synonymous variants nominated by this screen that co-segregate with hypopituitarism. This study underlines the importance of evaluating the impact of variants on splicing and provides a catalog for interpretation of variants of unknown significance in POU1F1.

The phenotypic spectrum associated with OTX2 mutations in humans

Objective

The transcription factor OTX2 is implicated in ocular, craniofacial, and pituitary development.

Design

We aimed to establish the contribution of OTX2 mutations in congenital hypopituitarism patients with/without eye abnormalities, study functional consequences, and establish OTX2 expression in the human brain, with a view to investigate the mechanism of action.

Methods

We screened patients from the UK (n = 103), international centres (n = 24), and Brazil (n = 282); 145 were within the septo-optic dysplasia spectrum, and 264 had no eye phenotype. Transactivation ability of OTX2 variants was analysed in murine hypothalamic GT1-7 neurons. In situ hybridization was performed on human embryonic brain sections. Genetically engineered mice were generated with a series of C-terminal OTX2 variants.

Results

Two chromosomal deletions and six haploinsufficient mutations were identified in individuals with eye abnormalities; an affected relative of one patient harboured the same mutation without an ocular phenotype. OTX2 truncations led to significant transactivation reduction. A missense variant was identified in another patient without eye abnormalities; however, studies revealed it was most likely not causative. In the mouse, truncations proximal to aa219 caused anophthalmia, while distal truncations and the missense variant were tolerated. During human embryogenesis, OTX2 was expressed in the posterior pituitary, retina, ear, thalamus, choroid plexus, and partially in the hypothalamus, but not in the anterior pituitary.

Conclusions

OTX2 mutations are rarely associated with hypopituitarism in isolation without eye abnormalities, and may be variably penetrant, even within the same pedigree. Our data suggest that the endocrine phenotypes in patients with OTX2 mutations are of hypothalamic origin.

Evaluation of Bone Age in Children: A Mini-Review

Bone age represents a common index utilized in pediatric radiology and endocrinology departments worldwide for the definition of skeletal maturity for medical and non-medical purpose. It is defined by the age expressed in years that corresponds to the level of maturation of bones. Although several bones have been studied to better define bone age, the hand and wrist X-rays are the most used images. In fact, the images obtained by hand and wrist X-ray reflect the maturity of different types of bones of the skeletal segment evaluated. This information, associated to the characterization of the shape and changes of bone components configuration, represent an important factor of the biological maturation process of a subject. Bone age may be affected by several factors, including gender, nutrition, as well as metabolic, genetic, and social factors and either acute and chronic pathologies especially hormone alteration. As well several differences can be characterized according to the numerous standardized methods developed over the past decades. Therefore, the complete characterization of the main methods and procedure available and particularly of all their advantages and disadvantages need to be known in order to properly utilized this information for all its medical and non-medical main fields of application.

Growth hormone deficiency and replacement in children

Growth hormone deficiency (GHD) is a rare but treatable cause of short stature. The diagnosis requires a careful evaluation of clinical history, physical examination and appropriate interpretation of longitudinal growth, with specific features for each period of life. Other clinical findings, in addition to growth failure, may be present and can be related to the etiology and to associated hormone deficiencies. Despite more than 50 years since the first reports of provocative tests of growth hormone (GH) secretion for the diagnosis of GHD, the interpretation of the results remains a matter of debate. When GHD is confirmed, GH treatment is recommended. Treatment is effective and safe, but requires daily injections during many years, which can affect adherence. At the end of longitudinal growth, during the transition phase, it might be necessary to re-evaluate GH secretion. This review summarizes and updates the recent information related to GHD in children, as well the recommendations for treatment.

Clinical lessons learned in constitutional hypopituitarism from two decades of experience in a large international cohort

CONTEXT

The international GENHYPOPIT network collects phenotypical data and screens genetic causes of non-acquired hypopituitarism.

AIMS

To describe main phenotype patterns and their evolution through life.

DESIGN

Patients were screened according to their phenotype for coding sequence variations in 8 genes: HESX1, LHX3, LHX4, PROP1, POU1F1, TBX19, OTX2 and PROKR2.

RESULTS

Among 1213 patients (1143 index cases), the age of diagnosis of hypopituitarism was congenital (24%), in childhood (28%), at puberty (32%), in adulthood (7.2%) or not available (8.8%). Noteworthy, pituitary hormonal deficiencies kept on evolving during adulthood in 49 of patients. Growth Hormone deficiency (GHD) affected 85.8% of patients and was often the first diagnosed deficiency. AdrenoCorticoTropic Hormone deficiency rarely preceded GHD, but usually followed it by over 10 years. Pituitary Magnetic Resonance Imaging (MRI) abnormalities were common (79.7%), with 39.4% pituitary stalk interruption syndrome (PSIS). The most frequently associated extrapituitary malformations were ophthalmological abnormalities (16.1%). Prevalence of identified mutations was 7.3% of index cases (84/1143) and 29.5% in familial cases (n = 146). Genetic analysis in 449 patients without extrapituitary phenotype revealed 36 PROP1, 2 POU1F1 and 17 TBX19 mutations.

CONCLUSION

This large international cohort highlights atypical phenotypic presentation of constitutional hypopituitarism, such as post pubertal presentation or adult progression of hormonal deficiencies. These results justify long-term follow-up, and the need for systematic evaluation of associated abnormalities. Genetic defects were rarely identified, mainly PROP1 mutations in pure endocrine phenotypes.

Diagnosis and Management of Central Congenital Hypothyroidism

Central congenital hypothyroidism (CH) is defined as thyroid hormone (TH) deficiency at birth due to insufficient stimulation by the pituitary of the thyroid gland. The incidence of central CH is currently estimated at around 1:13,000. Central CH may occur in isolation, but in the majority of cases (60%) it is part of combined pituitary hormone deficiencies (CPHD). In recent years several novel genetic causes of isolated central CH have been discovered (IGSF1, TBL1X, IRS4), and up to 90% of isolated central CH cases can be genetically explained. For CPHD the etiology usually remains unknown, although pituitary stalk interruption syndrome does seem to be the most common anatomic pituitary malformation associated with CPHD. Recent studies have shown that central CH is a more severe condition than previously thought, and that early detection and treatment leads to good neurodevelopmental outcome. However, in the neonatal period the clinical diagnosis is often missed despite hospital admission because of feeding problems, hypoglycemia and prolonged jaundice. This review provides an update on the etiology and prognosis of central CH, and a practical approach to diagnosis and management of this intriguing condition.

Whole Exome Sequencing Uncovered the Genetic Architecture of Growth Hormone Deficiency Patients

PURPOSE

Congenital growth hormone deficiency (GHD) is a rare and etiologically heterogeneous disease. We aim to screen disease-causing mutations of GHD in a relatively sizable cohort and discover underlying mechanisms via a candidate gene-based mutational burden analysis.

METHODS

We retrospectively analyzed 109 short stature patients associated with hormone deficiency. All patients were classified into two groups: Group I (n=45) with definitive GHD and Group II (n=64) with possible GHD. We analyzed correlation consistency between clinical criteria and molecular findings by whole exome sequencing (WES) in two groups. The patients without a molecular diagnosis (n=90) were compared with 942 in-house controls for the mutational burden of rare mutations in 259 genes biologically related with the GH axis.

RESULTS

In 19 patients with molecular diagnosis, we found 5 possible GHD patients received known molecular diagnosis associated with GHD (NF1 [c.2329T>A, c.7131C>G], GHRHR [c.731G>A], STAT5B [c.1102delC], HRAS [c.187_207dup]). By mutational burden analysis of predicted deleterious variants in 90 patients without molecular diagnosis, we found that POLR3A (p = 0.005), SUFU (p = 0.006), LHX3 (p = 0.021) and CREB3L4 (p = 0.040) represented top genes enriched in GHD patients.

CONCLUSION

Our study revealed the discrepancies between the laboratory testing and molecular diagnosis of GHD. These differences should be considered when for an accurate diagnosis of GHD. We also identified four candidate genes that might be associated with GHD.

Endocrine Dysfunction in Children with Zika-Related Microcephaly Who Were Born during the 2015 Epidemic in the State of Pernambuco, Brazil

Congenital viral infections and the occurrence of septo-optic dysplasia, which is a combination of optic nerve hypoplasia, abnormal formation of structures along the midline of the brain, and pituitary hypofunction, support the biological plausibility of endocrine dysfunction in Zika-related microcephaly. In this case series we ascertained the presence and describe endocrine dysfunction in 30 children with severe Zika-related microcephaly from the MERG Pediatric Cohort, referred for endocrinological evaluation between February and August 2019. Of the 30 children, 97% had severe microcephaly. The average age at the endocrinological consultation was 41 months and 53% were female. The most frequently observed endocrine dysfunctions comprised short stature, hypothyroidism, obesity and variants early puberty. These dysfunctions occurred alone 57% or in combination 43%. We found optic nerve hypoplasia (6/21) and corpus callosum hypoplasia (20/21). Seizure crises were reported in 86% of the children. The most common-and clinically important-endocrine dysfunctions were pubertal dysfunctions, thyroid disease, growth impairment, and obesity. These dysfunctions require careful monitoring and signal the need for endocrinological evaluation in children with Zika-related microcephaly, in order to make early diagnoses and implement appropriate treatment when necessary.

Current Insights Into Adrenal Insufficiency in the Newborn and Young Infant

Adrenal insufficiency (AI) is a potentially life-threatening condition that can be difficult to diagnose, especially if it is not considered as a potential cause of a child's clinical presentation or unexpected deterioration. Children who present with AI in early life can have signs of glucocorticoid deficiency (hyperpigmentation, hypoglycemia, prolonged jaundice, poor weight gain), mineralocorticoid deficiency (hypotension, salt loss, collapse), adrenal androgen excess (atypical genitalia), or associated features linked to a specific underlying condition. Here, we provide an overview of causes of childhood AI, with a focus on genetic conditions that present in the first few months of life. Reaching a specific diagnosis can have lifelong implications for focusing management in an individual, and for counseling the family about inheritance and the risk of recurrence.

Effect of growth hormone therapy on thyroid function in isolated growth hormone deficient and short small for gestational age children: a two-year study, including on assessment of the usefulness of the thyrotropin-releasing hormone (TRH) stimulation test

Background The relationship between growth hormone (GH)-replacement therapy and the thyroid axis in GH-deficient (GHD) children remains controversial. Furthermore, there have been few reports regarding non-GHD children. We aimed to determine the effect of GH therapy on thyroid function in GHD and non-GHD children and to assess whether thyrotropin-releasing hormone (TRH) stimulation test is helpful for the identification of central hypothyroidism before GH therapy. Methods We retrospectively analyzed data from patients that started GH therapy between 2005 and 2015. The free thyroxine (FT4) and thyroid-stimulating hormone (TSH) concentrations were measured before and during 24 months of GH therapy. The participants were 149 children appropriate for gestational age with GHD (IGHD: isolated GHD) (group 1), 29 small for gestational age (SGA) children with GHD (group 2), and 25 short SGA children (group 3). Results In groups 1 and 2, but not in group 3, serum FT4 concentration transiently decreased. Two IGHD participants exhibited central hypothyroidism during GH therapy, and required levothyroxine (LT4) replacement. They showed either delayed and/or prolonged responses to TRH stimulation tests before start of GH therapy. Conclusions GH therapy had little pharmacological effect on thyroid function, similar changes in serum FT4 concentrations were not observed in participants with SGA but not GHD cases who were administered GH at a pharmacological dose. However, two IGHD participants showed central hypothyroidism and needed LT4 replacement therapy during GH therapy. TRH stimulation test before GH therapy could identify such patients and provoke careful follow-up evaluation of serum FT4 and TSH concentrations.

Evolving pituitary hormone deficits in primarily isolated GHD: a review and experts' consensus

Isolated growth hormone deficiency (GHD) is defined by growth failure in combination with retarded bone age, low serum insulin-like growth factor-1, and insufficient GH peaks in two independent GH stimulation tests. Congenital GHD can present at any age and can be associated with significant malformations of the pituitary-hypothalamic region or the midline of the brain. In rare instances, genetic analysis reveals germline mutations of transcription factors involved in embryogenesis of the pituitary gland and the hypothalamus. Acquired GHD is caused by radiation, inflammation, or tumor growth. In contrast to organic GHD, idiopathic forms are more frequent and remain unexplained.There is a risk of progression from isolated GHD to combined pituitary hormone deficiency (> 5% for the total group), which is clearly increased in children with organic GHD, especially with significant malformation of the pituitary gland. Therefore, it is prudent to exclude additional pituitary hormone deficiencies in the follow-up of children with isolated GHD by clinical and radiological observations and endocrine baseline tests. In contrast to primary disorders of endocrine glands, secondary deficiency is frequently milder in its clinical manifestation. The pituitary hormone deficiencies can develop over time from mild insufficiency to severe deficiency. This review summarizes the current knowledge on diagnostics and therapy of additional pituitary hormone deficits occurring during rhGH treatment in children initially diagnosed with isolated GHD. Although risk factors are known, there are no absolute criteria enabling exclusion of children without any risk of progress to combined pituitary hormone deficiency. Lifelong monitoring of the endocrine function of the pituitary gland is recommended in humans with organic GHD. This paper is the essence of a workshop of pediatric endocrinologists who screened the literature for evidence with respect to evolving pituitary deficits in initially isolated GHD, their diagnosis and treatment.

LONG TERM FOLLOW-UP OF ONE OF THE FIRST PATIENTS TO RECEIVE HUMAN GROWTH HORMONE THERAPY

OBJECTIVE

Treatment of growth hormone (GH) deficiency with GH extracts from human pituitary glands was introduced by Dr. Maurice Raben at Tufts New England Medical Center in 1956. We report long term follow-up of one of the first patients treated with GH.

METHODS

Clinical, radiographic, and genetic data are presented.

RESULTS

A 78-year-old man presented for follow-up. He was one of the first patients to receive GH therapy from Raben in 1958. Growth was reported as normal until age 3 and then decelerated. At age 17 years, he was 129.5 cm with absent sexual development and bone age of 7 years. Treatment was initiated with desiccated thyroid and cortisone acetate for 8 months. Human GH extract was then initiated with 2 mg 3 times/week for 2 years, then 3 mg 3 times/week for 6 months, resulting in a final height of 168.9 cm. Testosterone intramuscularly every 2 weeks was added with sexual maturation over 2 years. He remained on testosterone injections until the age of 40 years, and on transdermal testosterone until the age of 50 years. At age 27 years, he was treated by Raben with human chorionic gonadotropin and menotropins for spermatogenesis restoration with successful conception by his wife. At age 78 years, pituitary MRI revealed a tiny amount of pituitary tissue within normal-sized sella turcica with absent pituitary infundibulum. A combined pituitary hormone deficiency genetic panel did not reveal any mutations.

CONCLUSION

Sixty-two years later, the patient remains in good health and grateful to a pioneer in Endocrinology for groundbreaking therapy of short stature. The cause of his hypopituitarism remains unknown.

The Molecular Basis of Congenital Hypopituitarism and Related Disorders

CONTEXT

Congenital hypopituitarism (CH) is characterized by the presence of deficiencies in one or more of the 6 anterior pituitary (AP) hormones secreted from the 5 different specialized cell types of the AP. During human embryogenesis, hypothalamo-pituitary (HP) development is controlled by a complex spatio-temporal genetic cascade of transcription factors and signaling molecules within the hypothalamus and Rathke's pouch, the primordium of the AP.

EVIDENCE ACQUISITION

This mini-review discusses the genes and pathways involved in HP development and how mutations of these give rise to CH. This may present in the neonatal period or later on in childhood and may be associated with craniofacial midline structural abnormalities such as cleft lip/palate, visual impairment due to eye abnormalities such as optic nerve hypoplasia (ONH) and microphthalmia or anophthalmia, or midline forebrain neuroradiological defects including agenesis of the septum pellucidum or corpus callosum or the more severe holoprosencephaly.

EVIDENCE SYNTHESIS

Mutations give rise to an array of highly variable disorders ranging in severity. There are many known causative genes in HP developmental pathways that are routinely screened in CH patients; however, over the last 5 years this list has rapidly increased due to the identification of variants in new genes and pathways of interest by next-generation sequencing.

CONCLUSION

The majority of patients with these disorders do not have an identified molecular basis, often making management challenging. This mini-review aims to guide clinicians in making a genetic diagnosis based on patient phenotype, which in turn may impact on clinical management.

Growth hormone deficiency with late-onset hypothalamic hypoadrenocorticism associated with respiratory and renal dysfunction: a case report

BACKGROUND

The prevalence of childhood-onset growth hormone (GH) deficiency (GHD) is estimated to be approximately 1 in 5000 or more, with the cause unknown in most cases (idiopathic isolated GHD). However, additional disorders of secretion of other pituitary hormones reportedly develop over time, with a frequency of 2-94% (median, 16%). Furthermore, median times to development of other anterior pituitary hormone deficiencies have been reported to be 6.4-9.4 years. On the other hand, adult patients affected by childhood-onset GHD reportedly develop impaired ventilation function due to reduced lung volumes and respiratory pressures, probably due to reductions in respiratory muscle strength. In addition, GH is known to play a role in stimulating the glomerular filtration rate (GFR), and the estimated GFR (eGFR) is decreased in patients with GHD.

CASE PRESENTATION

This case involved a 65-year-old woman. Her short stature had been identified at around 3 years of age, but no effective treatments had been provided. The patient was mostly amenorrheic, and hair loss became apparent in her late 30s. She developed hyperuricemia, dyslipidemia, and hypertension at 45 years of age. In addition, the patient was diagnosed with hypothyroidism at 50 years of age. At 58 years of age, endocrinological examination showed impaired secretion of thyroid-stimulating hormone, luteinizing hormone/follicle-stimulating hormone, and growth hormone, and magnetic resonance imaging showed an empty sella turcica. However, secretion ability of adrenocorticotropic hormone was retained. At 63 years of age, respiratory function tests confirmed a markedly restricted ventilation disorder (vital capacity, 0.54 L; percentage predicted vital capacity, 26.9%). Renal function had also decreased (eGFR, 25.0 mL/min/1.73 m²). Furthermore, she was diagnosed with hypothalamic secondary hypoadrenocorticism. The patient developed CO₂ narcosis at 65 years of age, and noninvasive positive pressure ventilation was started.

CONCLUSIONS

The rare case of a 65-year-old woman with childhood-onset GHD with panhypopituitarism, including late-onset secondary hypoadrenocorticism in her 60s, associated with severely impaired respiratory function and renal dysfunction, was reported. In GHD patients with risk factors for progression from isolated GHD to combined pituitary hormone deficiency, such as empty sella turcica, lifelong endocrinological monitoring may be important.

Growth and Adult Height during Human Growth Hormone Treatment in Chinese Children with Multiple Pituitary Hormone Deficiency Caused by Pituitary Stalk Interruption Syndrome: A Single Centre Study

OBJECTIVE

The aim was to assess growth velocity (GV) during human recombinant growth hormone (hGH) treatment of children with multiple pituitary hormone deficiency (MPHD) caused by pituitary stalk interruption syndrome (PSIS) and to analyze the characteristics of patients that attained normal adult heights.

METHODS

Data from 74 (16 female) children with MPHD caused by PSIS with GH, thyroid stimulating hormone, gonadotropin and adrenocorticotropic hormone deficiencies were collected. Subjects were divided into groups: 12 pre-pubescent females (Female-Group) and 36 pre-pubescent males (Male-Group 1). The remaining 22 males were further sub-divided into two groups (Male-Group 2 and Male-Group 3) according to the initiation of gonadotropin replacement treatment, based on bone age and height.

RESULTS

No differences in change in height standard deviation score (△HtSDS) and GV were observed at different time points of hGH treatment between the Female-Group and Male-Group 1 (p>0.05). GV was significantly greater in the first year of hGH therapy than in subsequent years: Female-Group p=0.011; Male-Group 1 p<0.001; Male-Group 2 p=0.005; and Male-Group 3 p=0.046. Adult height was achieved by 23 (19 males and 4 females) patients. The total gain in height positively correlated with the GV during the first year (r=0.626, p<0.001).

CONCLUSION

GV during hGH treatment were similar amongst pre-pubescent males and females with MPHD caused by PSIS. GV during the first year of hGH treatment appears to be an effective predictor of final height in patients with MPHD caused by PSIS.

Development and Validation of a Prediction Rule for Growth Hormone Deficiency Without Need for Pharmacological Stimulation Tests in Children With Risk Factors

INTRODUCTION

Practice guidelines cannot recommend establishing a diagnosis of growth hormone deficiency (GHD) without performing growth hormone stimulation tests (GHST) in children with risk factors, due to the lack of sufficient evidence.

OBJECTIVE

Our goal was to generate an evidence-based prediction rule to diagnose GHD in children with growth failure and clinically identifiable risk factors.

METHODS

We studied a cohort of children with growth failure to build the prediction model, and a second, independent cohort to validate the prediction rule. To this end, we assessed the existence of: pituitary dysgenesis, midline abnormalities, (supra)sellar tumor/surgery, CNS infection, traumatic brain injury, cranial radiotherapy, chemotherapy, genetic GHD, pituitary hormone deficiencies, and neonatal hypoglycemia, cholestasis, or hypogenitalism. Selection of variables for model building was performed using artificial intelligence protocols. Specificity of the prediction rule was the main outcome measure in the validation set.

RESULTS

In the first cohort (n=770), the resulting prediction rule stated that a patient would have GHD if (s)he had: pituitary dysgenesis, or two or more anterior pituitary deficiencies, or one anterior pituitary deficiency plus: neonatal hypoglycemia or hypogenitalism, or diabetes insipidus, or midline abnormalities, or (supra)sellar tumor/surgery, or cranial radiotherapy ≥18 Gy. In the validation cohort (n=161), the specificity of the prediction rule was 99.2% (95% CI: 95.6-100%).

CONCLUSIONS

This clinical rule predicts the existence of GHD with high specificity in children with growth disorders and clinically identifiable risk factors, thus providing compelling evidence to recommend that GHD can be safely diagnosed without recurring to GHST in neonates and children with growth failure and specific comorbidities.

Distinct pituitary hormone levels of 184 Chinese children and adolescents with multiple pituitary hormone deficiency: a single-centre study

BACKGROUND

Pituitary tumors and/or their treatment are associated with multiple pituitary hormone deficiency (MPHD) in adults, but the distinct pituitary hormone profile of MPHD in Chinese children and adolescents remains unclear.

METHODS

Patients with MPHD were divided into four groups according to their MRI results: 1) pituitary stalk interruption syndrome (PSIS); 2) hypoplasia; 3) normal; and 4) tumor survivor.

RESULTS

Among the 184 patients, 93 patients (50.5%) were with PSIS, 24 (13.0%) had hypoplastic pituitary gland, 10 (5.4%) patients were normal, and 57 (31.0%) were tumor survivors. There was an association between abnormal fetal position and PSIS (P ≤ 0.001). The CA/BA in PSIS, hypoplasia, normal, tumor survivor groups were 2.27 ± 1.05, 1.48 ± 0.39, 1.38 ± 0.57, 1.49 ± 0.33, and HtSDS were - 3.94 ± 1.39, - 2.89 ± 1.09, - 2.50 ± 1.05, - 1.38 ± 1.63. Patients in PSIS group had the largest CA/BA (P ≤ 0.001 vs. hypoplasia group, P = 0.009 vs. normal group, P ≤ 0.001 vs. tumor survivors) and lowest HtSDS (P ≤ 0.001 vs. hypoplasia group, P = 0.003 vs. normal group, P ≤ 0.001 vs. tumor survivors). The levels of TSH in the PSIS, hypoplasia, normal, and tumor survivor groups were 1.03 ± 1.08 (P = 0.149 vs. tumor survivors), 1.38 ± 1.47 (P = 0.045 vs. tumor survivors), 2.49 ± 1.53 (P < 0.001 vs. tumor survivors), and 0.76 ± 1.15 μIU/ml. The levels of GH peak in PSIS, hypoplasia, normal, tumor survivor groups were 1.37 ± 1.78, 1.27 ± 1.52, 3.36 ± 1.79, 0.53 ± 0.52 ng/ml and ACTH were 27.50 ± 20.72, 25.05 ± 14.64, 34.61 ± 59.35, 7.19 ± 8.63 ng/ml. Tumor survivors had the lowest levels of GH peak (P ≤ 0.001 vs. PSIS group, P = 0.002 vs. hypoplasia group, P ≤ 0.001 vs. normal group) and ACTH (all the P ≤ 0.001 vs. the other three groups).

CONCLUSION

The frequency of PSIS is high among children and adolescents with MPHD. The severity of hormone deficiencies in patients with MPHD was more important in the tumor survivor group compared with the other groups.

Causes and Follow-Up of Central Diabetes Insipidus in Children

OBJECTIVE

To identify the causes of central diabetes insipidus (CDI) by evaluating the values of magnetic resonance imaging (MRI) in the diagnosis of pediatric CDI, providing evidence for the clinical diagnosis and treatment of CDI.

METHODS

Seventy-nine patients with CDI (CDI group) hospitalized from July 2012 to March 2017 and 43 healthy children (control group) were enrolled in this study. All cases underwent MRI examination including T1-weighted three-dimensional magnetization-prepared rapid gradient-echo (T1WI-3D-MP RAGE) imaging sequences. The pituitary volume, the signal intensity of posterior pituitary, and the morphology of pituitary stalk were measured between two groups. The medical history, urine testing, imaging of hypothalamic-pituitary region, and hormone levels were also recorded.

RESULTS

Age and gender were matched between the CDI and control groups. The height and BMI in the CDI group were less and the urine volume in 24 h was higher than those in the control group. The signal intensity of the posterior pituitary was higher in the control group, whereas the pituitary volume was smaller in the CDI group. In the CDI group, 44 cases presented with morphological changes of the pituitary stalk. Clinical symptoms mainly included polydipsia, polyuria, short stature, and vomiting. All patients were confirmed by water deprivation vasopressin test. Forty-four CDI children were associated with hypopituitarism, including 33 cases of PSIS with multiple pituitary hormone deficiencies (MPHD) and 11 cases of growth hormone deficiency (IGHD). The pituitary volume in the cases of pituitary stalk interruption syndrome (PSIS) with MPHD was smaller than that in the IGHD patients.

CONCLUSIONS

The signal intensity ratio of the posterior lobe, pituitary volume, and the morphology of pituitary stalk on T1WI-3D-MP RAGE image contribute to the diagnosis of CDI.

Long-acting intramuscular ACTH stimulation test for the diagnosis of secondary adrenal insufficiency in children

Background The diagnosis of adrenal insufficiency (AI) is based on the basal and stimulated levels of serum cortisol in response to the short Synacthen test (SST). In patients with secondary AI (SAI) due to hypothalamic-pituitary-adrenal (HPA) axis defects, the SST has been validated against the insulin tolerance test (ITT), which is the gold standard. However, injection Synacthen is not easily available in some countries, and endocrinologists often use Acton-Prolongatum (intramuscular [IM] long-acting adrenocorticotropic hormone [ACTH]) in place of Synacthen. There are no studies validating the use of IM-ACTH in children with suspected AI. We evaluated the diagnostic value of the IM-ACTH test against the ITT for the diagnosis of SAI in children. Methods All children with suspected growth hormone deficiency (GHD) undergoing a routine ITT were evaluated using the IM-ACTH test within 1 week. Results Forty-eight patients (36 boys/12 girls, age range: 5-14 years) were evaluated using both the ITT and the IM-ACTH test. Twenty-eight patients had a normal cortisol response (≥18 μg/dL, 500 nmol/L) in the ITT and 20 had low values. In patients with a normal cortisol response on the ITT, the peak value obtained after the IM-ACTH test was higher than that on the ITT (28.7 μg/dL [± 8.8] vs. 23.8 μg/dL [± 4.54], respectively; p=0.0012). Compared to the ITT, the sensitivity and specificity of the IM-ACTH test for the diagnosis of SAI at cortisol cut-offs <18 μg/dL (500 nmol/L) and <22 μg/dL (600 nmol/L) were 57.1% and 92.8%, and 100% and 73.5%, respectively. Conclusions A peak cortisol value <18 μg/dL on the IM-ACTH test is highly suggestive of SAI, whereas a value >22 μg/dL rules out SAI.

Central adrenal insufficiency in children and adolescents

Central adrenal insufficiency (CAI) is a life-threatening condition caused by either pituitary disease (secondary adrenal insufficiency) or impaired hypothalamic function with inadequate CRH production (tertiary adrenal insufficiency). ACTH deficiency may be isolated or, more frequently, occur in conjunction with other pituitary hormone deficiencies and midline defects. Genetic mutations of the TBX19 causing isolated CAI are rare but a number of genes encoding transcription factors involved in hypothalamic-pituitary gland development, as well as other genes including POMC and PC1, are associated with ACTH deficiency. CAI is frequently identified in congenital, malformative, genetic, and epigenetic syndromes as well as in several acquired conditions of different etiologies. The signs and symptoms vary considerably and depend on the age of onset and the number and severity of associated pituitary defects. They may include hypoglycemia, lethargy, apnea, poor feeding, prolonged cholestatic jaundice, jitteriness, seizures, and sepsis in the neonate, or nonspecific signs such as fatigue, hypotension, vomiting and hyponatremia without hyperkalemia in children. The diagnosis of CAI relies on the measurement of morning cortisol concentrations along with dynamic test for cortisol release with different stimulating agents. Early recognition of CAI and its correct management are mandatory in order to avoid both morbidity and mortality in affected neonates, children and adolescents.

Molecular Mechanisms Governing Embryonic Differentiation of Pituitary Somatotropes

Pituitary somatotropes secrete growth hormone (GH), which is essential for normal growth and metabolism. Somatotrope defects result in GH deficiency (GHD), leading to short stature in childhood and increased cardiovascular morbidity and mortality in adulthood. Current hormone replacement therapies fail to recapitulate normal pulsatile GH secretion. Stem cell therapies could overcome this problem but are dependent on a thorough understanding of somatotrope differentiation. Although several transcription factors, signaling pathways, and hormones that regulate this process have been identified, the mechanisms of action are not well understood. The purpose of this review is to highlight the known players in somatotrope differentiation while emphasizing the need to better understand these pathways to serve patients with GHD.

Role of MRI T2-DRIVE in the assessment of pituitary stalk abnormalities without gadolinium in pituitary diseases

OBJECTIVE

To investigate the role of T2-DRIVE MRI sequence in the accurate measurement of pituitary stalk (PS) size and the identification of PS abnormalities in patients with hypothalamic-pituitary disorders without the use of gadolinium.

DESIGN

This was a retrospective study conducted on 242 patients who underwent MRI due to pituitary dysfunction between 2006 and 2015. Among 135 eligible patients, 102 showed eutopic posterior pituitary (PP) gland and 33 showed 'ectopic' PP (EPP).

METHODS

Two readers independently measured the size of PS in patients with eutopic PP at the proximal, midpoint and distal levels on pre- and post-contrast T1-weighted as well as T2-DRIVE images; PS visibility was assessed on pre-contrast T1 and T2-DRIVE sequences in those with EPP. The length, height, width and volume of the anterior pituitary (AP), PP height and length and PP area were analyzed.

RESULTS

Significant agreement between the two readers was obtained for T2-DRIVE PS measurements in patients with 'eutopic' PP; a significant difference was demonstrated between the intraclass correlation coefficient calculated on the T2-DRIVE and the T1-pre- and post-contrast sequences. The percentage of PS identified by T2-DRIVE in EPP patients was 72.7% compared to 30.3% of T1 pre-contrast sequences. A significant association was found between the visibility of PS on T2-DRIVE and the height of AP.

CONCLUSION

T2-DRIVE sequence is extremely precise and reliable for the evaluation of PS size and the recognition of PS abnormalities; the use of gadolinium-based contrast media does not add significant information and may thus be avoided.