EndoBridge 2023: highlights and pearls

EndoBridge 2023 took place on October 20-22, 2023, in Antalya, Turkey. Accredited by the European Council, the 3-day scientific program of the 11th Annual Meeting of EndoBridge included state-of-the-art lectures and interactive small group discussion sessions incorporating interesting and challenging clinical cases led by globally recognized leaders in the field and was well attended by a highly diverse audience. Following its established format over the years, the program provided a comprehensive update across all aspects of endocrinology and metabolism, including topics in pituitary, thyroid, bone, and adrenal disorders, neuroendocrine tumors, diabetes mellitus, obesity, nutrition, and lipid disorders. As usual, the meeting was held in English with simultaneous translation into Russian, Arabic, and Turkish. The abstracts of clinical cases presented by the delegates during oral and poster sessions have been published in JCEM Case Reports. Herein, we provide a paper on highlights and pearls of the meeting sessions covering a wide range of subjects, from thyroid nodule stratification to secondary osteoporosis and from glycemic challenges in post-bariatric surgery to male hypogonadism. This report emphasizes the latest developments in the field, along with clinical approaches to common endocrine issues. The 12th annual meeting of EndoBridge will be held on October 17-20, 2024 in Antalya, Turkey.

The spectrum of growth hormone excess in Carney complex and genotype-phenotype correlations

CONTEXT

Carney complex (CNC) is a familial neoplasia syndrome associated with growth hormone (GH) excess (GHE).

OBJECTIVE

To describe the frequency of GHE in a large cohort of patients with CNC, and to identify genotype-phenotype correlations.

METHODS

Patients with CNC with at least one biochemical evaluation of GH secretion at our center from 1995-2021 (n=140) were included in the study. Diagnosis of GHE was based on levels of insulin-like growth factor-1 (IGF-1), GH suppression during oral glucose tolerance test (OGTT), GH stimulation after thyrotropin (TRH) administration and overnight GH secretion.

RESULTS

Fifty patients (35.7%) had GHE and 28 subjects (20%) had symptomatic acromegaly, with median age at diagnosis of 25.3 and 26.1 years respectively. Most of the patients (99.3%) had a PRKAR1A gene defect. There was a higher risk of GHE in patients harboring a variant that led to no expression of the affected allele [Hazard risk (HR): 3.06, 95% Confidence Intervals (CI): 1.2-7.8] and for patients harboring the hotspot variant c.491_492delTG (HR: 2.10, 95%CI: 1.1-4.1). Almost half of patients with CNC had an abnormal finding on pituitary imaging. CNC patients with an abnormal pituitary imaging had higher risk of GHE (HR: 2.94, 95%CI: 1.5-5.8), especially when single or multiple adenoma-like lesions were identified. Management of patients with symptomatic acromegaly involved surgical and medical approaches.

CONCLUSION

Dysregulation of GH secretion is a common finding in CNC. The clinical spectrum of this disorder and its association with genetic and imaging characteristics of the patient make prompt diagnosis and management more successful.

GPR101: Modeling a constitutively active receptor linked to X-linked acrogigantism

GPR101 is a G protein-coupled receptor (GPCR) implicated in a rare form of genetic gigantism known as X-linked acrogigantism, or X-LAG. In particular, X-LAG patients harbor microduplications in the long arm of the X-chromosome that invariably include the GPR101 gene. Duplications of the GPR101 gene lead to the formation of a new chromatin domain that causes over-expression of the receptor in the pituitary tumors of the patients. Notably, GPR101 is a constitutively active receptor, which stimulates cells to produce the second messenger cyclic AMP (cAMP) in the absence of ligands. Moreover, GPR101 was recently reported to constitutively activate not only the cAMP pathway via Gs, but also other G protein subunits (Gq/11 and G12/13). Hence, chemicals that block the constitutive activity of GPR101, known as inverse agonists, have the potential to be useful for the development of pharmacological tools for the treatment of X-LAG. In this study, we provide structural insights into the putative structure of GPR101 based on in-house built homology models, as well as third party models based on the machine learning methods AlphaFold and AlphaFold-Multistate. Moreover, we report a molecular dynamics study, meant to further probe the constitutive activity of GPR101. Finally, we provide a structural comparison with the closest GPCRs, which suggests that GPR101 does not share their natural ligands. While this manuscript was under review, cryo-electron microscopy structures of GPR101 were reported. These structures are expected to enable computer-aided ligand discovery efforts targeting GPR101.

Lipodystrophy in methylmalonic acidemia associated with elevated FGF21 and abnormal methylmalonylation

A distinct adipose tissue distribution pattern was observed in patients with methylmalonyl-CoA mutase deficiency, an inborn error of branched-chain amino acid (BCAA) metabolism, characterized by centripetal obesity with proximal upper and lower extremity fat deposition and paucity of visceral fat, that resembles familial multiple lipomatosis syndrome. To explore brown and white fat physiology in methylmalonic acidemia (MMA), body composition, adipokines, and inflammatory markers were assessed in 46 patients with MMA and 99 matched controls. Fibroblast growth factor 21 levels were associated with acyl-CoA accretion, aberrant methylmalonylation in adipose tissue, and an attenuated inflammatory cytokine profile. In parallel, brown and white fat were examined in a liver-specific transgenic MMA mouse model (Mmut-/- TgINS-Alb-Mmut). The MMA mice exhibited abnormal nonshivering thermogenesis with whitened brown fat and had an ineffective transcriptional response to cold stress. Treatment of the MMA mice with bezafibrates led to clinical improvement with beiging of subcutaneous fat depots, which resembled the distribution seen in the patients. These studies defined what we believe to be a novel lipodystrophy phenotype in patients with defects in the terminal steps of BCAA oxidation and demonstrated that beiging of subcutaneous adipose tissue in MMA could readily be induced with small molecules.

The utility of IGF1 in the evaluation of pediatric patients with endogenous hypercortisolemia

BACKGROUND

Cushing Disease (CD) is a rare endocrine disorder associated with impaired growth hormone (GH) and short stature. Insulin-like growth factor-1 (IGF-1) is a marker of GH secretion.

METHODS

Patients with young onset CD (<21 years old) and available IGF-1 levels at diagnosis and/or follow-up were studied (total = 194, diagnosis = 174, follow-up = 104). IGF-1 was reported as z-score (IGF1z).

RESULTS

IGF1z was lower than expected in the general population (median IGF1z: -0.92 [-1.54, 0.07], p < 0.0001) at diagnosis and remained low at follow-up (median: -1.13 [-1.78, -0.66], p < 0.0001). There was no correlation of IGF1z at diagnosis with BMI; there was a weak correlation with height (rs = 0.19, p = 0.035). IGF1z was inversely correlated with markers of hypercortisolemia, including morning (rs = -0.31, p < 0.0001) and midnight cortisol (rs = -0.30, p < 0.0001), and with insulin resistance (Homeostatic Model Assessment for Insulin Resistance, HOMA-IR, rs = -0.27, p < 0.01).

CONCLUSIONS

IGF-1 levels in CS are on the lower side of the normal range during active disease and remain low at one year after treatment. IGF-1 levels correlated mainly with markers of hypercortisolemia rather than the short stature of patients and should not be used in the assessment of growth in this population.

IMPACT

We report that IGF-1 levels in childhood during active hypercortisolemia and up to 1 year after resolution are on the lower side of the normal range. Our results demonstrate that IGF-1 levels during active hypercortisolemia correlate mainly with markers of Cushing syndrome. This report adds data to the current literature where reports of IGF-1 in Cushing syndrome have shown variable results. Understanding the lack of utility of IGF-1 in assessing growth parameters in the pediatric Cushing syndrome population is important for physicians caring for these patients who should not use IGF-1 for diagnostic or treatment decisions.

Paediatric Cushing syndrome: a prospective, multisite, observational cohort study

BACKGROUND

Paediatric endogenous Cushing syndrome is a rare condition with variable signs and symptoms of presentation. We studied a large cohort of paediatric patients with endogenous Cushing syndrome with the aim of describing anthropometric, clinical, and biochemical characteristics as well as associated complications and outcomes to aid diagnosis, treatment, and management.

METHODS

In this prospective, multisite cohort study, we studied children and adolescents (≤18 years at time of presentation) with a diagnosis of Cushing syndrome. Patients had either received their initial diagnosis and evaluation at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (Bethesda, MD, USA) or been referred from other centres in the USA or outside the USA. We collected participants' clinical, biochemical, and imaging findings and recorded their post-operative course until their latest appointment.

FINDINGS

Of 342 paediatric patients with a diagnosis of Cushing syndrome, 193 (56%) were female and 149 (44%) male. 261 (76%) patients had corticotroph pituitary neuroendocrine tumours (Cushing disease), 74 (22%) had adrenal-associated Cushing syndrome, and seven (2%) had ectopic Cushing syndrome. Patients were diagnosed at a median of 2 years (IQR 1·0-3·0) after the first concerning sign or symptom, and patients with adrenal-associated Cushing syndrome were the youngest at diagnosis (median 10·4 years [IQR 7·4-13·6] vs 13·0 years [10·5-15·3] for Cushing disease vs 13·4 years [11·0-13·7] for ectopic Cushing syndrome; p<0·0001). Body-mass index z-scores did not differ between the diagnostic groups (1·90 [1·19-2·34] for adrenal-associated Cushing syndrome vs 2·18 [1·60-2·56] for Cushing disease vs 2·22 [1·42-2·35] for ectopic Cushing syndrome; p=0·26). Baseline biochemical screening for cortisol and adrenocorticotropin at diagnosis showed overlapping results between subtypes, and especially between Cushing disease and ectopic Cushing syndrome. However, patients with ectopic Cushing syndrome had higher urinary free cortisol (fold change in median cortisol concentration from upper limit of normal: 15·5 [IQR 12·7-18·0]) than patients with adrenal-associated Cushing syndrome (1·5 [0·6-5·7]) or Cushing disease (3·9 [2·3-6·9]; p<0·0001). Common complications of endogenous Cushing syndrome were hypertension (147 [52%] of 281 patients), hyperglycaemia (78 [30%] of 260 patients), elevated alanine transaminase (145 [64%] of 227 patients), and dyslipidaemia (105 [48%] of 219 patients). Long-term recurrence was noted in at least 16 (8%) of 195 patients with Cushing disease.

INTERPRETATION

This extensive description of a unique cohort of paediatric patients with Cushing syndrome has the potential to inform diagnostic workup, preventative actions, and follow-up of children with this rare endocrine condition.

FUNDING

Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health & Human Development, National Institutes of Health.

FAF1 Gene Involvement in Pituitary Corticotroph Tumors

Cushing's disease (CD) is caused by rare pituitary corticotroph tumors that lead to corticotropin (ACTH) excess. Variants in FAF1, a pro-apoptotic protein involved in FAS-induced cell death, have been implicated in malignant disorders but the involvement of FAF1 in pituitary tumors has not been studied. Genetic data from patients with CD were reviewed for variants in FAF1 gene. Knockout mice (KO) were followed to assess the development of any pituitary disorder or cortisol excess. AtT-20 cells were used to study the effects of the variants of interest on ACTH secretion and cell proliferation. Three variants of interest were identified in 5 unique patients, two of which had rare allele frequency in genomic databases and were predicted to be likely pathogenic. KO mice were followed over time and no difference in their length/weight was noted. Additionally, KO mice did not develop any pituitary lesions and retained similar corticosterone secretion with wild type. AtT-20 cells transfected with FAF1 variants of interest or WT expression plasmids showed no significant difference in cell death or Pomc gene expression. However, in silico prediction models suggested significant differences in secondary structures of the produced proteins. In conclusion, we identified two FAF1 variants in patients diagnosed with CD with a potential pathogenic effect on the protein function and structure. Our in vitro and in vivo studies did not reveal an association of FAF1 defects with pituitary tumorigenesis and further studies may be needed to understand any association.

Genes and environment: An old pair in a new era

What is the relationship between our genes and the environment we live in with regard to health? Like the debate about nature or nurture in the determination of our personality and behavior, the issue of genes and environment has been discussed intensely in the last two centuries. Is it Darwin or Lamarck who is right about the basic determinants of our health, especially as we age in a rapidly changing environment? Evolutionary biology as proposed by Darwin with natural selection at its core may not be able to explain almost instant adjustments of phenotypic traits to the pressures of the environment. Epigenesis, a concept that dates from Aristotle, provides a mechanism for the environment to affect variation in genetic traits that may become heritable. Indeed, Lamarck first described the inheritance of acquired characteristics. Thus, it appears that in contemporary genetics, both Darwin and Lamarck are right: environmental pressures may affect our genes through epigenetics, in ways that allow for inheritance of the changes, a Lamarckian concept; however, evolution through natural selection is the basis for incorporation (or rejection) of new traits and their sustained inheritance, a Darwinian concept. In this review, we present the synthesis of Darwin's and Lamarck's theories, the only way to understand how our health, and that of our progeny, responds to challenging and fast-changing environmental cues. In addition, we present other examples of environment-driven changes in disease frequency or expression.

PAM variants in patients with thyrotrophinomas, cyclical Cushing's disease and prolactinomas

Introduction

Germline loss-of-function variants in PAM, encoding peptidylglycine α-amidating monooxygenase (PAM), were recently discovered to be enriched in conditions of pathological pituitary hypersecretion, specifically: somatotrophinoma, corticotrophinoma, and prolactinoma. PAM is the sole enzyme responsible for C-terminal amidation of peptides, and plays a role in the biosynthesis and regulation of multiple hormones, including proopiomelanocortin (POMC).

Methods

We performed exome sequencing of germline and tumour DNA from 29 individuals with functioning pituitary adenomas (12 prolactinomas, 10 thyrotrophinomas, 7 cyclical Cushing's disease). An unfiltered analysis was undertaken of all PAM variants with population prevalence <5%.

Results

We identified five coding, non-synonymous PAM variants of interest amongst seven individuals (six germline, one somatic). The five variants comprised four missense variants and one truncating variant, all heterozygous. Each variant had some evidence of pathogenicity based on population prevalence, conservation scores, in silico predictions and/or prior functional studies. The yield of predicted deleterious PAM variants was thus 7/29 (24%). The variants predominated in individuals with thyrotrophinomas (4/10, 40%) and cyclical Cushing's disease (2/7, 29%), compared to prolactinomas (1/12, 8%).

Conclusion

This is the second study to demonstrate a high yield of suspected loss-of-function, predominantly germline, PAM variants in individuals with pathological pituitary hypersecretion. We have extended the association with corticotrophinoma to include the specific clinical entity of cyclical Cushing's disease and demonstrated a novel association between PAM variants and thyrotrophinoma. PAM variants might act as risk alleles for pituitary adenoma formation, with a possible genotype-phenotype relationship between truncating variants and altered temporal secretion of cortisol.

High-frequency variants in PKA signaling-related genes within a large pediatric cohort with obesity or metabolic abnormalities

Introduction

Pediatric obesity has steadily increased in recent decades. Large-scale genome-wide association studies (GWAS) conducted primarily in Eurocentric adult populations have identified approximately 100 loci that predispose to obesity and type II diabetes. GWAS in children and individuals of non-European descent, both disproportionately affected by obesity, are fewer. Rare syndromic and monogenic obesities account for only a small portion of childhood obesity, so understanding the role of other genetic variants and their combinations in heritable obesities is key to developing targeted and personalized therapies. Tight and responsive regulation of the cAMP-dependent protein kinase (PKA) signaling pathway is crucial to maintaining healthy energy metabolism, and mutations in PKA-linked genes represent the most common cause of monogenic obesity.

Methods

For this study, we performed targeted exome sequencing of 53 PKA signaling-related genes to identify variants in genomic DNA from a large, ethnically diverse cohort of obese or metabolically challenged youth.

Results

We confirmed 49 high-frequency variants, including a novel variant in the PDE11A gene (c.152C>T). Several other variants were associated with metabolic characteristics within ethnic groups.

Discussion

We conclude that a PKA pathway-specific variant search led to the identification of several new genetic associations with obesity in an ethnically diverse population.

Diurnal Range and Intra-patient Variability of ACTH Is Restored With Remission in Cushing's Disease

CONTEXT

Single ACTH measurements have limited ability to distinguish patients with Cushing's disease (CD) from those in remission or with other conditions.

OBJECTIVE

To investigate the changes in ACTH levels before and after transsphenoidal surgery (TSS) to identify trends that could confirm remission from CD and help establish ACTH cutoffs for targeted clinical trials in CD.

DESIGN

Retrospective analysis of CD patients who underwent TSS from 2005 to -2019.

SETTING

Referral center.

PATIENTS

CD patients (n = 253) with ACTH measurements before and after TSS.

INTERVENTIONS

TSS for CD.

MAIN OUTCOME MEASURES

Remission after TSS.

RESULTS

Remission was observed in 223 patients after TSS. Those in remission had higher ACTH variability at AM (P = .02) and PM (P < .001) time points compared to nonremission. The nonremission group had a significantly narrower diurnal range compared to the remission group (P = <.0001). A decrease in plasma ACTH of ≥50% from mean preoperative levels predicted CD remission after TSS, especially when using PM values. The absolute plasma ACTH concentration and ratio of preoperative to postoperative values were significantly associated with nonremission after multivariable logistic regression (adj P < .001 and .001, respectively).

CONCLUSIONS

Our findings suggest that ACTH variability is suppressed in CD, and remission from CD is associated with the restoration of this variability. Furthermore, a decrease in plasma ACTH by 50% or more may serve as a predictor of remission post-TSS. These insights could guide clinicians in developing rational outcome measures for interventions targeting CD adenomas.

Embryonic stem cell factor FOXD3 (Genesis) defects in gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms, believed to originate from the interstitial cells of Cajal (ICC), often caused by overexpression of tyrosine kinase receptors (TKR) KIT or PDGFRA. Here, we present evidence that the embryonic stem cell factor FOXD3, first identified as 'Genesis' and involved in both gastrointestinal and neural crest cell development, is implicated in GIST pathogenesis; its involvement is investigated both in vitro and in zebrafish and a mouse model of FOXD3 deficiency. Samples from a total of 58 patients with wild-type GISTs were used for molecular analyses, including Sanger sequencing, comparative genomic hybridization, and methylation analysis. Immunohistochemistry and western blot evaluation were used to assess FOXD3 expression. Additionally, we conducted in vitro functional studies in tissue samples and in transfected cells to confirm the pathogenicity of the identified genetic variants. Germline partially inactivating FOXD3 sequence variants (p.R54H and p.Ala88_Gly91del) were found in patients with isolated GISTs. Chromosome 1p loss was the most frequent chromosomal abnormality identified in tumors. In vitro experiments demonstrate the impairment of FOXD3 in the presence of those variants. Animal studies showed disruption of the GI neural network and changes in the number and distribution in the ICC. FOXD3 suppresses KIT expression in human cells; its inactivation led to an increase in ICC in zebrafish, as well as mice, providing evidence for a functional link between FOXD3 defects and KIT overexpression leading to GIST formation.

A Novel Variant in the TP53 Gene Causing Li-Fraumeni Syndrome

Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary cancer syndrome associated with germline pathogenic variants in the tumor protein p53 (TP53) gene and elevated risk of a broad range of early-onset malignancies. Patients with LFS are at risk of a second and third primary tumor. A 15-month-old girl consulted for clitoromegaly and pubic hair. Adrenal ultrasound detected a large left adrenal tumor. Left total adrenalectomy confirmed adrenocortical carcinoma. Family history revealed multiple highly malignant neoplasms at an early age across five generations, and a genetic dominant trait seemed probable. Whole-genome sequencing was performed. Multiple members of the family were found positive for a novel likely pathogenic variant (c. 892delGinsTTT, p. Glu298PhefsX48, NM_000546.6) in the TP53 gene, causing the loss of normal protein function through non-sense-mediated mRNA decay. According to the PSV1 supporting criteria and the Auto PVS1 online tool this frameshift variant: hg19/17-7577045-TC-TAAA:NM_000546.6 has a very strong, definitive clinical validity for LFS with autosomal dominant inheritance. Proper guidance resulted in timely diagnosis of a second tumor (primary osteosarcoma) in the index case and in the early detection of breast and cervical cancer in her young mother. Patients with cancer predisposition syndromes like LFS require close multidisciplinary cancer surveillance and appropriate referral to expert centers.

An update on, and genetics of refractory adenomas of childhood

Pituitary adenomas in childhood tend to be more frequently due to germline genetic changes and are often diagnosed at late stages due to delayed recognition by pediatricians and other caretakers who are not familiar with this rare disease in childhood. As a result, often, pediatric pituitary adenomas are aggressive or remain refractory to treatment. In this review, we discuss germline genetic defects that account for the most common pediatric pituitary adenomas that are refractory to treatment. We also discuss some somatic genetic events, such as chromosomal copy number changes that characterize some of the most aggressive pituitary adenomas in childhood that end up being refractory to treatment.

Germline loss-of-function PAM variants are enriched in subjects with pituitary hypersecretion

Introduction

Pituitary adenomas (PAs) are common, usually benign tumors of the anterior pituitary gland which, for the most part, have no known genetic cause. PAs are associated with major clinical effects due to hormonal dysregulation and tumoral impingement on vital brain structures. PAM encodes a multifunctional protein responsible for the essential C-terminal amidation of secreted peptides.

Methods

Following the identification of a loss-of-function variant (p.Arg703Gln) in the peptidylglycine a-amidating monooxygenase (PAM) gene in a family with pituitary gigantism, we investigated 299 individuals with sporadic PAs and 17 familial isolated PA kindreds for PAM variants. Genetic screening was performed by germline and tumor sequencing and germline copy number variation (CNV) analysis.

Results

In germline DNA, we detected seven heterozygous, likely pathogenic missense, truncating, and regulatory SNVs. These SNVs were found in sporadic subjects with growth hormone excess (p.Gly552Arg and p.Phe759Ser), pediatric Cushing disease (c.-133T>C and p.His778fs), or different types of PAs (c.-361G>A, p.Ser539Trp, and p.Asp563Gly). The SNVs were functionally tested in vitro for protein expression and trafficking by Western blotting, splicing by minigene assays, and amidation activity in cell lysates and serum samples. These analyses confirmed a deleterious effect on protein expression and/or function. By interrogating 200,000 exomes from the UK Biobank, we confirmed a significant association of the PAM gene and rare PAM SNVs with diagnoses linked to pituitary gland hyperfunction.

Conclusion

The identification of PAM as a candidate gene associated with pituitary hypersecretion opens the possibility of developing novel therapeutics based on altering PAM function.

Molecular tools for diagnosing diseases of the adrenal cortex

PURPOSE OF REVIEW

The adrenal glands produce some of the most essential for life hormones, including cortisol and other steroids, and catecholamines. The former is produced from the adrenal cortex, whereas the latter is from the medulla. The two parts are anatomically and functionally distinct and it would be impossible in the context of one short article to cover all molecular updates on both the cortex and the medulla. Thus, in this review, we focus on the molecular tools available for diagnosing adrenocortical diseases, such as adrenal insufficiency, Cushing and Conn syndromes, and their potential for advancing medical care and clinical outcome.

RECENT FINDINGS

The advent of next generation sequencing opened doors for finding genetic diseases and signaling pathways involved in adrenocortical diseases. In addition, the combination of molecular data and clinicopathologic assessment might be the best approach for an early and precise diagnosis contributing to therapeutic decisions and improvement of patient outcomes.

SUMMARY

Diagnosing adrenocortical diseases can be challenging; however, the progress of molecular tools for adrenocortical disease diagnosis has greatly contributed to early detection and to meliorate patient outcomes.

Exploratory Study of the Association of Genetic Factors With Recovery of Adrenal Function in Cushing Disease

Successful treatment of endogenous Cushing disease (CD) is often followed by a period of adrenal insufficiency (AI). We performed an exploratory study on genetic factors potentially involved in the hypothalamic-pituitary-adrenal (HPA) axis recovery in patients with CD after remission. We identified 90 patients who achieved remission after surgery and had a minimum of 3 months follow-up. Variants in a selected panel of genes that were rare in the general population and predicted as damaging in silico were retrieved from whole exome sequencing analysis. We did not identify any variant with significant correlation with recovery time after adjusting for multiple comparisons. On gene-specific analysis the BAG1 gene showed a correlation with shorter duration of postsurgical AI, but both patients with BAG1 variants later experienced a recurrence. After excluding patients with recurrence, no statistical association was recorded. To conclude, we did not identify a strong genetic modifier of HPA recovery in this exploratory study.

Genomic analysis, immunomodulation and deep phenotyping of patients with nodding syndrome

The aetiology of nodding syndrome remains unclear, and comprehensive genotyping and phenotyping data from patients remain sparse. Our objectives were to characterize the phenotype of patients with nodding syndrome, investigate potential contributors to disease aetiology, and evaluate response to immunotherapy. This cohort study investigated members of a single-family unit from Lamwo District, Uganda. The participants for this study were selected by the Ugandan Ministry of Health as representative for nodding syndrome and with a conducive family structure for genomic analyses. Of the eight family members who participated in the study at the National Institutes of Health (NIH) Clinical Center, three had nodding syndrome. The three affected patients were extensively evaluated with metagenomic sequencing for infectious pathogens, exome sequencing, spinal fluid immune analyses, neurometabolic and toxicology testing, continuous electroencephalography and neuroimaging. Five unaffected family members underwent a subset of testing for comparison. A distinctive interictal pattern of sleep-activated bursts of generalized and multifocal epileptiform discharges and slowing was observed in two patients. Brain imaging showed two patients had mild generalized cerebral atrophy, and both patients and unaffected family members had excessive metal deposition in the basal ganglia. Trace metal biochemical evaluation was normal. CSF was non-inflammatory and one patient had CSF-restricted oligoclonal bands. Onchocerca volvulus-specific antibodies were present in all patients and skin snips were negative for active onchocerciasis. Metagenomic sequencing of serum and CSF revealed hepatitis B virus in the serum of one patient. Vitamin B6 metabolites were borderline low in all family members and CSF pyridoxine metabolites were normal. Mitochondrial DNA testing was normal. Exome sequencing did not identify potentially causal candidate gene variants. Nodding syndrome is characterized by a distinctive pattern of sleep-activated epileptiform activity. The associated growth stunting may be due to hypothalamic dysfunction. Extensive testing years after disease onset did not clarify a causal aetiology. A trial of immunomodulation (plasmapheresis in two patients and intravenous immunoglobulin in one patient) was given without short-term effect, but longer-term follow-up was not possible to fully assess any benefit of this intervention.

Germline loss-of-function PAM variants are enriched in subjects with pituitary hypersecretion

Pituitary adenomas (PAs) are common, usually benign tumors of the anterior pituitary gland which, for the most part, have no known genetic cause. PAs are associated with major clinical effects due to hormonal dysregulation and tumoral impingement on vital brain structures. Following the identification of a loss-of-function variant (p.Arg703Gln) in the PAM gene in a family with pituitary gigantism, we investigated 299 individuals with sporadic PAs and 17 familial isolated pituitary adenomas kindreds for PAM variants. PAM encodes a multifunctional protein responsible for the essential C-terminal amidation of secreted peptides. Genetic screening was performed by germline and tumor sequencing and germline copy number variation (CNV) analysis. No germline CNVs or somatic single nucleotide variants (SNVs) were identified. We detected seven likely pathogenic heterozygous missense, truncating, and regulatory SNVs. These SNVs were found in sporadic subjects with GH excess (p.Gly552Arg and p.Phe759Ser), pediatric Cushing disease (c.-133T>C and p.His778fs), or with different types of PAs (c.-361G>A, p.Ser539Trp, and p.Asp563Gly). The SNVs were functionally tested in vitro for protein expression and trafficking by Western blotting, for splicing by minigene assays, and for amidation activity in cell lysates and serum samples. These analyses confirmed a deleterious effect on protein expression and/or function. By interrogating 200,000 exomes from the UK Biobank, we confirmed a significant association of the PAM gene and rare PAM SNVs to diagnoses linked to pituitary gland hyperfunction. Identification of PAM as a candidate gene associated with pituitary hypersecretion opens the possibility of developing novel therapeutics based on altering PAM function.

Aortic Intima-Media Thickness is Increased in Neonates of Mothers with Gestational Diabetes Mellitus: The Role of Thioredoxin-Interacting Protein as a Marker of Oxidative Stress

BACKGROUND

Offspring exposed in foetal life to gestational diabetes mellitus (GDM) are at increased risk for future metabolic diseases.

OBJECTIVE

To explore the prognostic role of abdominal aorta intima-media thickness (aIMT) in neonates exposed to GDM as a possible biomarker for later atherogenesis and its possible correlation with thioredoxin- interacting protein (TXNIP), a protein involved in oxidative stress.

METHODS

In this prospective, observational study, mother-infant pairs were studied in 2 groups (57 patients with GDM and 51 controls without GDM). TXNIP levels were measured in the placenta, as well as in the umbilical and neonatal blood. The data were correlated with aIMT in neonates.

RESULTS

aIMT was increased in GDM offspring (patients: median [range]=0.39 mm [0.31-0.46] vs controls: median=0.28 mm [0.23-0.33]; p=0.001) and remained significant after adjusting for possible confounders (e.g., triglycerides, blood pressure, vitamin D, birth weight and gender; β coefficient=0.131 p=0.049). TXNIP levels were increased in trophoblasts (p=0.001) and syncytiotrophoblasts (p=0.001) and were decreased in endothelial cells (p=0.022) in GDM offspring vs controls. Moreover, TXNIP levels in trophoblasts positively correlated with aIMT (r=0.369; p=0.001). TXNIP levels in umbilical/ neonatal blood were not associated with GDM.

CONCLUSION

Increased aIMT was demonstrated in the offspring of mothers with GDM. Non-invasive measurement of aIMT could be used as a biomarker to identify children at increased risk for atherogenesis later in life. This information may encourage early preventive measures. TXNIP may be associated with GDM and/or aIMT.

Genetic drivers of Cushing's disease: Frequency and associated phenotypes

PURPOSE

Cushing's disease (CD) is often explained by a single somatic sequence change. Germline defects, however, often go unrecognized. We aimed to determine the frequency and associated phenotypes of genetic drivers of CD in a large cohort.

METHODS

We studied 245 unrelated patients with CD (139 female, 56.7%), including 230 (93.9%) pediatric and 15 (6.1%) adult patients. Germline exome sequencing was performed in 184 patients; tumor exome sequencing was also done in 27 of them. A total of 43 germline samples and 92 tumor samples underwent Sanger sequencing of specific genes. Rare variants of uncertain significance, likely pathogenic (LP), or pathogenic variants in CD-associated genes, were identified.

RESULTS

Germline variants (13 variants of uncertain significance, 8 LP, and 11 pathogenic) were found in 8 of 19 patients (42.1%) with positive family history and in 23 of 226 sporadic patients (10.2%). Somatic variants (1 LP and 7 pathogenic) were found in 20 of 119 tested individuals (16.8%); one of them had a coexistent germline defect. Altogether, variants of interest were identified at the germline level in 12.2% of patients, at the somatic level in 7.8%, and coexisting germline and somatic variants in 0.4%, accounting for one-fifth of the cohort.

CONCLUSION

We report an estimate of the contribution of multiple germline and somatic genetic defects underlying CD in a single cohort.

Primary bilateral macronodular adrenal hyperplasia: definitely a genetic disease

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is an adrenal cause of Cushing syndrome. Nowadays, a PBMAH diagnosis is more frequent than previously, as a result of progress in the diagnostic methods for adrenal incidentalomas, which are widely available. Although some rare syndromic forms of PBMAH are known to be of genetic origin, non-syndromic forms of PBMAH have only been recognized as a genetic disease in the past 10 years. Genomics studies have highlighted the molecular heterogeneity of PBMAH and identified molecular subgroups, allowing improved understanding of the clinical heterogeneity of this disease. Furthermore, the generation of these subgroups permitted the identification of new genes responsible for PBMAH. Constitutive inactivating variants in ARMC5 and KDM1A are responsible for the development of distinct forms of PBMAH. To date, pathogenic variants of ARMC5 are responsible for 20-25% of PBMAH, whereas germline KDM1A alterations have been identified in >90% of PBMAH causing food-dependent Cushing syndrome. The identification of pathogenic variants in ARMC5 and KDM1A demonstrated that PBMAH, despite mostly being diagnosed in adults aged 45-60 years, is a genetic disorder. This Review summarizes the important progress made in the past 10 years in understanding the genetics of PBMAH, which have led to a better understanding of the pathophysiology, opening new clinical perspectives.

RF01 | PMON167 Isolated Cushing's Disease Associated With Rare Germline SDHx Variants

Introduction

Loss-of-function (LOF) germline variants in the SDHx genes (SDHA, SDHB, SDHC, and SDHD), encoding the succinate dehydrogenase subunits, are a rare cause for pituitary tumors in the setting of various familial tumor syndromes. Occasional case reports have highlighted SDHx mutations in isolated pituitary tumors (including one case of Cushing's disease, CD). The actual frequency of SDHx variants as genetic drivers of pituitary tumors, however, remains elusive.

Aim

We sought to determine the frequency of germline SDHx variants in a large cohort of CD patients.

Methods

Of the 245 unrelated CD patients studied (139 females, 56.7%; 230 pediatric, 93.9%), 184 underwent whole-exome sequencing (WES) of peripheral blood and 27 of them underwent additional tumor WES. Forty-three additional germline samples and 92 tumor samples underwent Sanger sequencing of specific genes. Rare variants of uncertain significance (VUS), likely pathogenic or pathogenic variants of the SDHx genes were reviewed. Immunocytochemistry was used to analyze protein expression in tumor samples.

Results

Germline heterozygous variants of SDHA (three missense and one frameshift) and SDHD (two missense) were identified in six patients (four female; mean age of 8.8±2.2 years at onset of CD and 11.5±2.6 years at diagnosis). The variants were inherited in all 5 cases where parental germline samples were available. We found the following SDHA variants: Case 1 carried p.A21T (absent from gnomAD), Case 2 carried p.L74Ffs*9 (absent from gnomAD), Case 3 carried p.I235T (allele frequency, MAF=0.0100% in gnomAD exomes), and Case 4 carried p.H424Q (MAF=0.0056% in gnomAD exomes). Two patients (Cases 5 and 6) carried the SDHD missense VUS c.53C>T, p.A18V (MAF= 0.0068% in gnomAD exomes). Case 6 had a maternal family history of familial isolated pituitary adenomas, but an SDHD variant of paternal origin; disease presentation was apparently sporadic in the rest of cases. Case 2 displayed somatic loss of heterozygosity (LOH) for the SDHA variant, while no LOH was found in the three other cases tested. Somatic hotspot variants were absent in all tumors tested in USP8 (5/5 cases), USP48 (4/4 cases), and BRAF (4/4 cases). All patients carried microadenomas and achieved remission after one transsphenoidal surgery. Case 4 was diagnosed with a Crooke's cell corticotropinoma and also carried germline VUS in DICER1 and TSC2. In all three tumors tested, SDHx subunit expression was reduced: SDHB reduced in Cases 2, 4, and 5; SDHA reduced in Cases 2 and 4; absent SDHD in Case 2, and absent SDHC in case 5.

Conclusion

Altogether, SDHx variants were found in 2.4% of the cohort (2.6% of pediatric patients). Our findings suggest that germline SDHx variants are a rare but significant genotype associated with isolated sporadic Cushing's disease.

* JLM and CAS contributed equally.

Presentation: Saturday, June 11, 2022 1:24 p.m. - 1:29 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Cushing's disease in children: unique features and update on genetics

In this brief report, we review the unique characteristics of Cushing disease (CD) in children, as well as the most important new genetic discoveries associated with childhood CD. We often forget it, but CD refers to Cushing syndrome caused by pituitary corticotroph adenomas only. Thus, here we only refer to the new discoveries associated with pituitary tumors. There is indeed a wealth of new information on clinical features, outcomes, and genetic determinants of CD in children!

Update on the Genetics of Primary Aldosteronism and Aldosterone-Producing Adenomas

PURPOSE OF THE REVIEW

Primary aldosteronism (PA) is the leading cause of secondary hypertension, accounting for over 10% of patients with high blood pressure. It is characterized by autonomous production of aldosterone from the adrenal glands leading to low-renin levels. The two most common forms arise from bilateral adrenocortical hyperplasia (BAH) and aldosterone-producing adenoma (APA). We discuss recent discoveries in the genetics of PA.

RECENT FINDINGS

Most APAs harbor variants in the KCNJ5, CACNA1D, ATP1A1, ATP2B3, and CTNNB1 genes. With the exception of β-catenin (CTNNB1), all other causative genes encode ion channels; pathogenic variants found in PA lead to altered ion transportation, cell membrane depolarization, and consequently aldosterone overproduction. Some of these genes are found mutated in the germline state (CYP11B2, CLCN2, KCNJ5, CACNA1H, and CACNA1D), leading then to familial hyperaldosteronism, and often BAH rather than single APAs. Several genetic defects in the germline or somatic state have been identified in PA. Understanding how these molecular abnormalities lead to excess aldosterone contributes significantly to the elucidation of the pathophysiology of low-renin hypertension. It may also lead to new and more effective therapies for this disease acting at the molecular level.

Whole exome sequencing in patients with ectopic posterior pituitary

Context

Ectopic posterior pituitary (EPP), a condition in which the posterior pituitary gland is displaced due to defective neuronal migration, is frequently associated with hypopituitarism. Genetic variants play a role, but many cases remain unexplained.

Objective

A large EPP cohort was studied to explore the importance of genetic variants and how they correlate with clinical findings.

Methods

Whole exome sequencing was performed on a discovery sample of 27 cases to identify rare variants. The variants that met the criteria for rarity and biological relevance, or that were previously associated with EPP (ROBO1 and HESX1), were then resequenced in the 27 cases plus a replication sample of 51 cases.

Results

We identified 16 different variants in 12 genes in 15 of the 78 cases (19.2%). Complete anterior pituitary deficiency was twice as common in cases with variants of interest compared to cases without variants (9/15; 60% vs. 19/63; 30.1%, respectively; Z test; p=0.06). Breech presentation was more frequent in the variant positive group (5/15 vs. 1/63; Z test; p= 0.003). Four cases had variants in ROBO1 and one in HESX1, genes previously associated with EPP. The ROBO1 p.S18* variant has not been reported previously; ROBO1 p.Q1227H has not been associated with EPP previously.

Conclusions

EPP cases with variants of interest identified in this study were more likely to present with severe clinical disease. Several variants were identified in genes not previously associated with EPP. Our findings confirm that EPP is a multigenic disorder. Future studies are needed to identify additional genes.

USP13 genetics and expression in a family with thyroid cancer

PURPOSE

Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma and its incidence has greatly increased in the last 30 years. Ubiquitin-specific protease 13 (USP13) is a class of deubiquitinating enzymes (DUBs) and plays an important role in cellular functions such as cell cycle regulation, DNA damage repair, and different cell signaling pathways. Studies regarding the role of USP13 in cancer development and progression are divergent and there are no previous data regarding the role of USP13 gene in PTCs. In this study, we investigated the genetic cause of PTC diagnosed in multiple members of a Brazilian family.

METHODS

Whole exome sequencing (WES) was performed to identify the genetic cause of PTC. Cycloheximide chase assay and clonogenic assay were performed to study USP13 stability and function in vitro.

RESULTS

WES analysis identified a heterozygous missense variant c.1483G > A (p.V495M) in the USP13 gene that fully segregates with the disease. In silico modeling suggests that this variant may cause protein structural perturbations. USP13 overexpression increased the potential of a single cell to form colonies. The USP13 c.1483G > A variant enhanced the effects seen in USP13 overexpression and preserved protein stability for longer hours compared to the non-mutated USP13 protein.

CONCLUSION

Our study suggests that USP13 overexpression may play a role in tumorigenesis of PTCs; and that the USP13 p.V495M (c.1483G > A) variant enhances USP13 estability.

The pediatric glucocorticoid toxicity index

OBJECTIVES

To develop a Pediatric glucocorticoid toxicity index (pGTI), a standardized, weighted clinical outcome assessment that measures change in glucocorticoid (GC) toxicity over time.

METHODS

Fourteen physician experts from 7 subspecialties participated. The physician experts represented multiple subspecialties in which GCs play a major role in the treatment of inflammatory disease: nephrology, rheumatology, oncology, endocrinology, genetics, psychiatry, and maternal-fetal medicine. Nine investigators were from Canada, Europe, or New Zealand, and 5 were from the United States. Group consensus methods and multi-criteria decision analysis were used. The pGTI is an aggregate assessment of GC toxicities that are common, important, and dynamic. These toxicities are organized into health domains graded as minor, moderate, or major and are weighted according to severity. The relative weights were derived by group consensus and multi-criteria decision analysis using the 1000Minds^TM software platform. Two quantitative scores comprise the overall toxicity profile derived from pGTI data: (1) the Cumulative Worsening Score; and (2) the Aggregate Improvement Score. The pGTI also includes a qualitative, unweighted record of GC side-effects known as the Damage Checklist, which documents less common toxicities that, although potentially severe, are unlikely to change with varying GC dosing.

RESULTS

One hundred and seven (107) toxicity items were included in the pGTI and thirty-two (32) in the Damage Checklist. To assess the degree to which the pGTI corresponds to expert clinical judgement, the investigators ranked 15 cases by clinical judgement from highest to lowest GC toxicity. Expert rankings were then compared to case ranking by the pGTI, yielding excellent agreement (weighted kappa 0.86). The pGTI was migrated to a digital environment following its development and initial validation. The digital platform is designed to ensure ease-of-use in the clinic, rigor in application, and accuracy of scoring. Clinic staff enter vital signs, laboratory results, and medication changes relevant to pGTI scoring. Clinicians record findings for GC myopathy, skin toxicity, mood dysfunction, and infection. The pGTI algorithms then apply the weights to these raw data and calculate scores. Embedded logic accounts for the impact of age- and sex-related reference ranges on several health domains: blood pressure, lipid metabolism, and bone mineral density. Other algorithms account for anticipated changes in the height Z-scores used in the growth domain, thereby addressing a concern unique to GC toxicity in children. The Damage Checklist ensures comprehensive measurement of GC toxicity but does not contribute to pGTI scoring, because the scored domains emphasize manifestations of GC toxicity that are likely to change over the course of a trial.

CONCLUSIONS

We describe the development and initial evaluation of a weighted, composite toxicity index for the assessment of morbidity related to GC use in children and adolescents. Developing the pGTI digital platform was essential for performing the nuanced calculations necessary to ensure rigor, accuracy, and ease-of-use in both clinic and research settings.

Subclinical hemorrhage in pediatric and adolescent ACTH-secreting pituitary adenomas changes their biochemical profile

Background

Subclinical pituitary hemorrhage, necrosis and/or cystic degeneration (SPH) presents mainly in large tumors and prolactinomas. The characteristics of patients with Cushing disease (CD) and SPH are not known.

Subjects and methods

Pediatric and adolescent patients who were diagnosed with CD between 2005-2021 and available MRI images were evaluated for SPH. The clinical and biochemical characteristics of patients with and without SPH were compared.

Results

Evidence of possible SPH was present in 12 out of 170 imaging studies (7.1%). Patients with and without SPH had similar age at diagnosis and gender distribution but differed in disease duration (median duration: 1.0 year [1.0, 2.0] in SPH group vs 2.5 years [1.5, 3.0] in non-SPH group, p= 0.014). When comparing their biochemical evaluation, patients with SPH had higher levels of morning ACTH (60.8 pg/mL [43.5, 80.3]) compared to patients without SPH (39.4 pg/mL [28.2, 53.2], p=0.016) and the degree of cortisol reduction after overnight high dose (8mg or weight-based equivalent) dexamethasone was lower (-58.0% [-85.4, -49.7]) compared to patients without SPH (85.8 [-90.5, -76.8], p= 0.035). The presence of SPH did not affect the odds of remission after surgery or the risk of recurrence after initial remission.

Conclusion

SPH in ACTH-secreting pituitary adenomas may affect their biochemical response during endocrine evaluations. They may, for example, fail to suppress to dexamethasone which can complicate diagnosis. Thus, SPH should be mentioned upon imaging and taken into consideration in the work up of pediatric patients with CD.

Steroidogenic factor-1 lineage origin of skin lesions in Carney complex syndrome

Carney complex (CNC) is a rare familial multi-neoplastic syndrome predisposing to endocrine and non-endocrine tumors due to inactivating mutations of PRKAR1A leading to perturbations of the cAMP protein kinase A (PKA) signaling pathway. Skin lesions are the most common manifestation of CNC, including lentigines, blue nevi and cutaneous myxomas, in unusual locations such as oral and genital mucosa. Unlike endocrine disorders, the pathogenesis of skin lesions remains unexplained. Here, we show that embryonic invalidation of the Prkar1a gene in Steroidogenic Factor-1-expressing cells, leads to the development of familial skin pigmentation alterations reminiscent of those in patients. Immunohistological and molecular analyses coupled with genetic monitoring of recombinant cell lineages in mouse skin, suggest that familial lentiginosis and myxomas occurs in skin areas specifically enriched in dermal melanocytes. In lentigines and blue nevi-prone areas from mutant mice and patients, Prkar1a/PRKAR1A invalidation occurs in a subset of dermal fibroblasts capable of inducing, under the influence of PKA signaling, the production of pro-melanogenic EDN3 and HGF signals. Our model strongly suggests that the origin of the typical CNC cutaneous lesions is the result of non-cell-autonomous pro-melanogenic activity of a dermal fibroblast population sharing a community of origin with SF-1 lineage.

Genetic Alterations in Benign Adrenal Tumors

The genetic basis of most types of adrenal adenomas has been elucidated over the past decade, leading to the association of adrenal gland pathologies with specific molecular defects. Various genetic studies have established links between variants affecting the protein kinase A (PKA) signaling pathway and benign cortisol-producing adrenal lesions. Specifically, genetic alterations in GNAS, PRKAR1A, PRKACA, PRKACB, PDE11A, and PDE8B have been identified. The PKA signaling pathway was initially implicated in the pathogenesis of Cushing syndrome in studies aiming to understand the underlying genetic defects of the rare tumor predisposition syndromes, Carney complex, and McCune-Albright syndrome, both affected by the same pathway. In addition, germline variants in ARMC5 have been identified as a cause of primary bilateral macronodular adrenal hyperplasia. On the other hand, primary aldosteronism can be subclassified into aldosterone-producing adenomas and bilateral idiopathic hyperaldosteronism. Various genes have been reported as causative for benign aldosterone-producing adrenal lesions, including KCNJ5, CACNA1D, CACNA1H, CLCN2, ATP1A1, and ATP2B3. The majority of them encode ion channels or pumps, and genetic alterations lead to ion transport impairment and cell membrane depolarization which further increase aldosterone synthase transcription and aldosterone overproduction though activation of voltage-gated calcium channels and intracellular calcium signaling. In this work, we provide an overview of the genetic causes of benign adrenal tumors.

Duplications disrupt chromatin architecture and rewire GPR101-enhancer communication in X-linked acrogigantism

X-linked acrogigantism (X-LAG) is the most severe form of pituitary gigantism and is characterized by aggressive growth hormone (GH)-secreting pituitary tumors that occur in early childhood. X-LAG is associated with chromosome Xq26.3 duplications (the X-LAG locus typically includes VGLL1, CD40LG, ARHGEF6, RBMX, and GPR101) that lead to massive pituitary tumoral expression of GPR101, a novel regulator of GH secretion. The mechanism by which the duplications lead to marked pituitary misexpression of GPR101 alone was previously unclear. Using Hi-C and 4C-seq, we characterized the normal chromatin structure at the X-LAG locus. We showed that GPR101 is located within a topologically associating domain (TAD) delineated by a tissue-invariant border that separates it from centromeric genes and regulatory sequences. Next, using 4C-seq with GPR101, RBMX, and VGLL1 viewpoints, we showed that the duplications in multiple X-LAG-affected individuals led to ectopic interactions that crossed the invariant TAD border, indicating the existence of a similar and consistent mechanism of neo-TAD formation in X-LAG. We then identified several pituitary active cis-regulatory elements (CREs) within the neo-TAD and demonstrated in vitro that one of them significantly enhanced reporter gene expression. At the same time, we showed that the GPR101 promoter permits the incorporation of new regulatory information. Our results indicate that X-LAG is a TADopathy of the endocrine system in which Xq26.3 duplications disrupt the local chromatin architecture forming a neo-TAD. Rewiring GPR101-enhancer interaction within the new regulatory unit is likely to cause the high levels of aberrant expression of GPR101 in pituitary tumors caused by X-LAG.

Copeptin Levels Before and After Transsphenoidal Surgery for Cushing Disease: A Potential Early Marker of Remission

Context

Arginine-vasopressin (AVP) and corticotropin-releasing hormone (CRH) act synergistically to stimulate secretion of adrenocorticotropic hormone (ACTH). There is evidence that glucocorticoids act via negative feedback to suppress AVP secretion.

Objective

Our hypothesis was that a post-operative increase in plasma copeptin may serve as a marker of remission of Cushing Disease (CD).

Design

Plasma copeptin was obtained in patients with CD before and daily on post-operative days 1-8 after transsphenoidal surgery. Peak post-operative copeptin levels and Δcopeptin values were compared among those in remission versus no remission.

Results

Forty-four patients (64% female, 7-55 years old) were included, and 19 developed neither DI nor SIADH. Thirty-three had follow-up at least 3 months post-operatively. There was no difference in peak post-operative copeptin in remission [6.1 pmol/L (4.3-12.1)] versus no remission [7.3 pmol/L (5.4-8.4), p=0.88].. Excluding those who developed DI or SIADH, there was no difference in peak post-operative copeptin in remission [10.2 pmol/L (6.9-21.0)] versus no remission [5.4 pmol/L (4.6-7.3), p= 0.20]. However, a higher peak post-operative copeptin was found in those in remission [14.6 pmol/L (±10.9) vs. 5.8 (±1.4), p=0.03]] with parametric testing. There was no difference in the Δcopeptin by remission status.

Conclusions

A difference in peak post-operative plasma copeptin as an early marker to predict remission of CD was not consistently present, although the data point to the need for a larger sample size to further evaluate this. However, the utility of this test may be limited to those who develop neither DI nor SIADH post-operatively.

Younger age and early puberty are associated with cognitive function decline in children with Cushing disease

OBJECTIVE

To investigate the effect of hypercortisolism on the developing brain we performed clinical, cognitive, and psychological evaluation of children with Cushing disease (CD) at diagnosis and 1 year after remission.

STUDY DESIGN

Prospective study of 41 children with CD. Children completed diverse sets of cognitive measures before and 1 year after remission. Neuropsychological evaluation included the Wechsler Intelligence Scale, California Verbal Learning Test, Trail Making Test, the combined subset scores of Wide Range Achievement Test and Woodcock-Johnson Psychoeducational Battery Test of Achievement, and the Behavioral Assessment System for Children.

RESULTS

Comprehensive cognitive evaluations at baseline and 1 year following cure revealed significant decline mostly in nonverbal skills. Decrements occurred in most of the various indices that measure all aspects of cognitive function and younger age and early pubertal stage largely contributed to most of this decline. Results indicated that age at baseline was associated with positive regression weights for changes in scores for verbal, performance, and full intelligence quotient (IQ) scores and for subtests arithmetic, picture completion, coding, block design, scores; indicating that older age at baseline was associated with less of a deterioration in cognitive scores from pre- to posttreatment.

CONCLUSION

Our findings suggest that chronic glucocorticoid excess and accompanying secondary hormonal imbalances followed by eucortisolemia have detrimental effects on cognitive function in the developing brain; younger age and pubertal stage are risk factors for increased vulnerability, while older adolescents have cognitive vulnerabilities like that of adult patients affected with CD.

Inflammatory biomarkers in the evaluation of pediatric endogenous Cushing syndrome

OBJECTIVE

Inflammatory biomarkers, such as absolute neutrophil and lymphocyte counts, neutrophil-to-lymphocyte ratio (NLR), platelet (PLT)-to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR), are associated with the progression and development of several disorders. Although patients with Cushing syndrome (CS) have immunosuppression with altered leucocyte counts, the profile of the inflammatory biomarkers in these patients has not been extensively studied.

DESIGN

We compared a panel of inflammatory biomarkers in patients with active endogenous CS (n of complete blood count (CBC) reports = 319) and eucortisolemic subjects of similar age, gender and BMI (n of CBC reports = 93). Patients were divided into two age groups (6-12 years at the time of CBC and >12 years at the time of CBC) based on age differences in normal reference ranges.

RESULTS

Patients with CS had higher NLR vs controls (6-12 years: 2.47 (1.86, 3.32) vs 1.35 (1.11, 2.27), P < 0.0001; >12 years: 3.00 (2.23-4.17) vs 1.80 (1.23-2.31), P < 0.0001). Similarly, absolute neutrophil and lymphocyte counts, MLR and PLR differed between patients with CS and controls. The inflammatory biomarkers correlated with indices of cortisol secretion, such as midnight serum cortisol, 24-h urinary free cortisol and morning cortisol. On receiver operating characteristic analysis, NLR showed high area under the curve (AUC) (6-12 years: cutoff of 1.72 had AUC: 0.77, >12 years: cutoff of 2.35 had AUC: 0.81).

CONCLUSIONS

We conclude that multiple inflammatory biomarkers differed between patients with CS and controls suggesting substantial effects of hypercortisolemia on the immune system.

The regulation of PKA signaling in obesity and in the maintenance of metabolic health

The cAMP-dependent protein kinase (PKA) system represents a primary cell-signaling pathway throughout systems and across species. PKA facilitates the actions of hormones, neurotransmitters and other signaling molecules that bind G-protein coupled receptors (GPCR) to modulate cAMP levels. Through its control of synaptic events, exocytosis, transcriptional regulation, and more, PKA signaling regulates cellular metabolism and emotional and stress responses making it integral in the maintenance and dysregulation of energy homeostasis. Neural PKA signaling is regulated by afferent and peripheral efferent signals that link specific neural cell populations to the regulation of metabolic processes in adipose tissue, liver, pancreas, adrenal, skeletal muscle, and gut. Mouse models have provided invaluable information on the roles for PKA subunits in brain and key metabolic organs. While limited, human studies infer differential regulation of the PKA system in obese compared to lean individuals. Variants identified in PKA subunit genes cause Cushing syndrome that is characterized by metabolic dysregulation associated with endogenous glucocorticoid excess. Under healthy physiologic conditions, the PKA system is exquisitely regulated by stimuli that activate GPCRs to alter intracellular cAMP concentrations, and by PKA cellular localization and holoenzyme stability. Adenylate cyclase activity generates cAMP while phosphodiesterase-mediated cAMP degradation to AMP decreases cAMP levels downstream of GPCRs. Chronic perturbations in PKA signaling appear to be capable of resetting PKA regulation at several levels; in addition, sex differences in PKA signaling regulation, while not well understood, impact the physiologic consequences of metabolic dysregulation and obesity. This review explores the roles for PKA signaling in the pathogenesis of metabolic diseases including obesity, type 2 diabetes mellitus and associated co-morbidities through neural-peripheral crosstalk and cAMP/PKA signaling pathway targets that hold therapeutic potential.

Family environment and development in children adopted from institutionalized care

BACKGROUND

After adoption, children exposed to institutionalized care show significant improvement, but incomplete recovery of growth and developmental milestones. There is a paucity of data regarding risk and protective factors in children adopted from institutionalized care. This prospective study followed children recently adopted from institutionalized care to investigate the relationship between family environment, executive function, and behavioral outcomes.

METHODS

Anthropometric measurements, physical examination, endocrine and bone age evaluations, neurocognitive testing, and behavioral questionnaires were evaluated over a 2-year period with children adopted from institutionalized care and non-adopted controls.

RESULTS

Adopted children had significant deficits in growth, cognitive, and developmental measurements compared to controls that improved; however, residual deficits remained. Family cohesiveness and expressiveness were protective influences, associated with less behavioral problems, while family conflict and greater emphasis on rules were associated with greater risk for executive dysfunction.

CONCLUSIONS

Our data suggest that a cohesive and expressive family environment moderated the effect of pre-adoption adversity on cognitive and behavioral development in toddlers, while family conflict and greater emphasis on rules were associated with greater risk for executive dysfunction. Early assessment of child temperament and parenting context may serve to optimize the fit between parenting style, family environment, and the child's development.

IMPACT

Children who experience institutionalized care are at increased risk for significant deficits in developmental, cognitive, and social functioning associated with a disruption in the development of the prefrontal cortex. Aspects of the family caregiving environment moderate the effect of early life social deprivation in children. Family cohesiveness and expressiveness were protective influences, while family conflict and greater emphasis on rules were associated with a greater risk for executive dysfunction problems. This study should be viewed as preliminary data to be referenced by larger studies investigating developmental and behavioral outcomes of children adopted from institutional care.

Adrenal hyperplasias in childhood: An update

Pediatric adrenocortical hyperplasias are rare; they usually present with Cushing syndrome (CS); of them, isolated micronodular adrenal disease and its variant, primary pigmented adrenocortical disease are the most commonly encountered. Most cases are due to defects in the cyclic AMP/protein kinase A (cAMP/PKA) pathway, although a few cases remain without an identified genetic defect. Another cause of adrenal hyperplasia in childhood is congenital adrenal hyperplasia, a group of autosomal recessive disorders that affect steroidogenic enzymes in the adrenal cortex. Clinical presentation varies and depends on the extent of the underlying enzymatic defect. The most common form is due to 21-hydroxylase deficiency; it accounts for more than 90% of the cases. In this article, we discuss the genetic etiology of adrenal hyperplasias in childhood.

Paediatric patients with Cushing disease and negative pituitary MRI have a higher risk of nonremission after transsphenoidal surgery

OBJECTIVE

Diagnostic workup of Cushing disease (CD) involves imaging evaluation of the pituitary gland, but in many patients no tumour is visualised. The aim of this study is to describe the association of magnetic resonance imaging (MRI) findings with the postoperative course of paediatric and adolescent patients with CD.

PATIENTS

Patients with a diagnosis of CD at less than 21 years of age with MRI evaluation of the pituitary before first transsphenoidal surgery were included.

MEASUREMENTS

Clinical, imaging and biochemical data were analysed.

RESULTS

One hundred and eighty-six patients with paediatric or adolescent-onset CD were included in the study. Of all patients, 127 (68.3%) had MRI findings consistent with pituitary adenoma, while the remaining had negative or inconclusive MRI. Patients with negative MRI were younger in age and had lower morning cortisol and adrenocorticotropin levels. Of 181 patients with data on postoperative course, patients with negative MRI had higher odds of not achieving remission after the first surgery (odds ratio = 2.6, 95% confidence intervals [CIs] = 1.1-6.0) compared to those with positive MRI. In patients with remission after first transsphenoidal surgery, long-term recurrence risk was not associated with the detection of a pituitary adenoma in the preoperative MRI (hazard risk = 2.1, 95% CI = 0.7-5.8).

CONCLUSIONS

Up to one-third of paediatric and adolescent patients with CD do not have a pituitary tumour visualised in MRI. A negative MRI is associated with higher odds of nonremission after surgery; however, if remission is achieved, long-term risk for recurrence is not associated with the preoperative MRI findings.

Consensus on diagnosis and management of Cushing's disease: a guideline update

Cushing's disease requires accurate diagnosis, careful treatment selection, and long-term management to optimise patient outcomes. The Pituitary Society convened a consensus workshop comprising more than 50 academic researchers and clinical experts to discuss the application of recent evidence to clinical practice. In advance of the virtual meeting, data from 2015 to present about screening and diagnosis; surgery, medical, and radiation therapy; and disease-related and treatment-related complications of Cushing's disease summarised in recorded lectures were reviewed by all participants. During the meeting, concise summaries of the recorded lectures were presented, followed by small group breakout discussions. Consensus opinions from each group were collated into a draft document, which was reviewed and approved by all participants. Recommendations regarding use of laboratory tests, imaging, and treatment options are presented, along with algorithms for diagnosis of Cushing's syndrome and management of Cushing's disease. Topics considered most important to address in future research are also identified.