MANAGEMENT OF ENDOCRINE DISEASE: Diagnostic and therapeutic approach of tall stature

Genomic Effects of Biomechanical Loading in Adolescent Human Growth Plate Cartilage: A Pilot Study

OBJECTIVE

The genomic effects of biomechanical loading on human growth plate cartilage are unknown so far. To address this, we used rare human growth plate biopsies obtained from children undergoing epiphysiodesis and exposed them to precisely controlled mechanical loading using a microloading device. The biopsies were cultured 24 hours after mechanical loading, followed by RNA-sequencing analyses to decipher the genomic regulation.

DESIGN

We conducted RNA-seq analysis of human growth plate cartilage obtained from three patients cultured ex vivo and subjected to cyclical mechanical loading with peak 0.4 N with frequency 0.77 Hz during a 30-second duration, using a specialized microloading device.

RESULTS

Gene ontology analysis revealed novel data showing three significantly upregulated signaling pathways, including notch, oxytocin, and tight junction, and three significantly downregulated signaling pathways, including lysosome, sphingolipid metabolism, and peroxisome proliferator-activated receptor (PPAR) in human growth plate cartilage. Moreover, we found 15 significantly regulated genes within these signaling pathways from all three patients. These genes included PSEN2, HEY1, and NCOR2 from the notch signaling; CACNB1 and PPP3R2 from the oxytocin signaling; ACTR3C, WHAMM, and ARHGEF18 from the tight junction signaling; ARSA, SMPD1, and CD68 from the lysosome signaling; ARSA and SMPD1 from the sphingolipid metabolism signaling; and SLC27A4 and AQP7 from the PPAR signaling pathway. In addition, 20 significantly upregulated genes and six significantly downregulated genes shared between two patient samples were identified.

CONCLUSION

Our study provides the first-ever transcriptomic data of mechanical loading of human growth plate cartilage. These findings can potentially provide genetic targets for future investigations in physiological and pathological bone growth conditions.

The Genetic Pathophysiology and Clinical Management of the TADopathy, X-Linked Acrogigantism

Pituitary gigantism is a rare manifestation of chronic growth hormone (GH) excess that begins before closure of the growth plates. Nearly half of patients with pituitary gigantism have an identifiable genetic cause. X-linked acrogigantism (X-LAG; 10% of pituitary gigantism) typically begins during infancy and can lead to the tallest individuals described. In the 10 years since its discovery, about 40 patients have been identified. Patients with X-LAG usually develop mixed GH and prolactin macroadenomas with occasional hyperplasia that secrete copious amounts of GH, and frequently prolactin. Circulating GH-releasing hormone is also elevated in a proportion of patients. X-LAG is caused by constitutive or sporadic mosaic duplications at chromosome Xq26.3 that disrupt the normal chromatin architecture of a topologically associating domain (TAD) around the orphan G-protein-coupled receptor, GPR101. This leads to the formation of a neo-TAD in which GPR101 overexpression is driven by ectopic enhancers ("TADopathy"). X-LAG has been seen in 3 families due to transmission of the duplication from affected mothers to sons. GPR101 is a constitutively active receptor with an unknown natural ligand that signals via multiple G proteins and protein kinases A and C to promote GH/prolactin hypersecretion. Treatment of X-LAG is challenging due to the young patient population and resistance to somatostatin analogs; the GH receptor antagonist pegvisomant is often an effective option. GH, insulin-like growth factor 1, and prolactin hypersecretion and physical overgrowth can be controlled before definitive adult gigantism occurs, often at the cost of permanent hypopituitarism.

Association between Height and Functional Outcomes of Patients 6 Months after a Stroke: A Multicenter Prospective Observational Cohort Study

Many physical factors influence post-stroke functional outcomes. However, few studies have examined the influence of height on these outcomes. Here, data from the Korean Stroke Cohort for Functioning and Rehabilitation were used and patients' height was categorized into three groups: short (lower 25%), middle (middle 50%), and tall (upper 25%). Differences in the modified Rankin scale (mRS), functional ambulatory category (FAC), and Korean-translated version of the Modified Barthel Index (K-MBI) scores were analyzed for each group at 6 months post-stroke. A subgroup analysis was conducted based on the initial Fugl-Meyer Assessment (FMA) score. We analyzed functional outcomes in 5296 patients at 6 months post-stroke, adjusting for age and body mass index. The short-height group exhibited higher mRS scores (1.88 ± 0.043), lower FAC scores (3.74 ± 0.045), and lower K-MBI scores (82.83 ± 0.748) than the other height groups (p < 0.05). In the subgroup analysis, except for the very severe FMA group, the short-height group also exhibited worse outcomes in terms of mRS, FAC, and K-MBI scores (p < 0.05). Taken together, the short-height group exhibited worse outcomes related to disability, gait function, and ADLs at 6 months post-stroke.

Pseudoacromegaly-A challenging entity in the endocrine clinic: A systematic review

OBJECTIVE

Pseudoacromegaly encompasses conditions with features of acromegaly/gigantism, but no growth hormone (GH) or insulin-like growth factor-1 (IGF-1) excess. We aimed to review published pseudoacromegaly cases evaluated due to clinical suspicion of acromegaly.

DESIGN/PATIENTS

PubMed/Medline search was conducted to identify reported pseudoacromegaly cases, which were systematically reviewed to ensure they met eligibility criteria: (1) presentation suggestive of acromegaly; (2) acromegaly excluded based on normal GH, IGF-1 and/or GH suppression on oral glucose tolerance test (OGTT-GH); (3) diagnosis of the pseudoacromegaly condition was established. Data were retrieved from each case and analysed collectively.

RESULTS

Of 76 cases, 47 were males, mean ages at presentation and at first acromegaloid symptoms were 28 ± 16 and 17 ± 10 years, respectively. Most common conditions were pachydermoperiostosis (47%) and insulin-mediated pseudoacromegaly (IMP) (24%). Acromegaloid facies (75%) and acral enlargement (80%) were the most common features. Measurement of random GH was reported in 65%, IGF-1 in 79%, OGTT-GH in 51%. GH excess was more frequently excluded based on two tests (53%). Magnetic resonance imaging (MRI) was performed in 30 patients, with pituitary adenoma or hyperplasia being reported in eight and three patients, respectively. Investigations differed between cases managed by endocrine and non-endocrine specialists, the former requesting more often IGF-1, OGTT-GH and pituitary MRI.

CONCLUSIONS

Pseudoacromegaly is a challenging entity that may be encountered by endocrinologists. Pachydermoperiostosis and IMP are the conditions most often mimicking acromegaly. Adequate assessment of GH/IGF-1 is crucial to exclude acromegaly, which may be better performed by endocrinologists. Pituitary incidentalomas are common and require careful judgement to prevent unnecessary pituitary surgery.

Tall stature and gigantism in transition age: clinical and genetic aspects-a literature review and recommendations

PURPOSE

Tall stature is defined as height greater than the threshold of more than 2 standard deviations above the average population height for age, sex, and ethnicity. Many studies have described the main aspects of this condition during puberty, but an analysis of the characteristics that the physician should consider in the differential diagnosis of gigantism-tall stature secondary to a pituitary tumour-during the transition age (15-25 years) is still lacking.

METHODS

A comprehensive search of English-language original articles was conducted in the MEDLINE database (December 2021-March 2022). We selected all studies regarding epidemiology, genetic aspects, and the diagnosis of tall stature and gigantism during the transition age.

RESULTS

Generally, referrals for tall stature are not as frequent as expected because most cases are familial and are usually unreported by parents and patients to endocrinologists. For this reason, lacking such experience of tall stature, familiarity with many rarer overgrowth syndromes is essential. In the transition age, it is important but challenging to distinguish adolescents with high constitutional stature from those with gigantism. Pituitary gigantism is a rare disease in the transition age, but its systemic complications are very relevant for future health. Endocrine evaluation is crucial for identifying conditions that require hormonal treatment so that they can be treated early to improve the quality of life and prevent comorbidities of individual patient in this age range.

CONCLUSION

The aim of our review is to provide a practical clinical approach to recognise adolescents, potentially affected by gigantism, as early as possible.

Tall stature and gigantism in adult patients with acromegaly

OBJECTIVES

Increased height in patients with acromegaly could be a manifestation of growth hormone (GH) excess before epiphysis closure. The aim of this study was to evaluate the relationship between the height of adult patients with GH excess related to mid-parental height (MPH) and population mean and to find whether taller patients with acromegaly come from tall families.

METHODS

This is a single-centre, observational study involving 135 consecutive patients with acromegaly diagnosed as adults and no family history of GH excess. We established three categories for height for patients with acromegaly: normal stature, tall stature (TS, height above the 97th percentile (1.88 standard deviations (SD)) to <3 SD for gender- and country-specific data or as a height which was greater than 1.5 SD but less than 2 SD above the MPH) and gigantism (height which was greater than 3 SD) above the gender- and country-specific mean or greater than 2 SD above MPH).

RESULTS

Thirteen percent (17/135) of patients (53% females) met the criteria for gigantism, 10% (14/135) fulfilled the criteria for TS (57% females). Parents and adult siblings were not taller than the population mean.

CONCLUSION

In a group of 135 consecutive adult patients with acromegaly, 23% had increased height based on country-specific and MPH data: 13% presented with gigantism while 10% had TS. The frequency of gigantism and TS in patients diagnosed with GH excess as adults is not higher in males than in females. Patients with acromegaly come from normal-stature families.

The Treatment of Growth Disorders in Childhood and Adolescence

BACKGROUND

3% of all children are unusually short, and 3% are unusually tall. New approaches have broadened the range of therapeutic options in treating growth disorders.

METHODS

This review is based on publications retrieved by a selective review of the literature and on the authors' clinical experience.

RESULTS

Pituitary growth hormone deficiency is treated with recombinant growth hormone. Long-acting preparations of this type became available recently, but their long-term safety and efficacy are still unknown. Vosoritide, a CNP analogue, has also been approved for the treatment of achondroplasia, and severe primary deficiency of insulin-like growth factor 1 (IGF-1) can be treated with recombinant IGF-1. In the treatment of excessively tall stature, new information on the safety of growth-attenuating treatment and an altered perception of above-average height in society have led to a change in management.

CONCLUSION

There are new options for the treatment of rare causes of short stature, while new information on the safety of treatment strategies for excessive tallness have led to a reconsideration of surgical intervention. There is insufficient evidence on the benefits and risks of supraphysiological GH therapy and of newer treatment options for which there are as yet no robust data on adult height. Therefore, before any treatment is provided, physicians should give patients and their families detailed information and discuss their expectations from treatment and the goals that treatment can be expected to achieve.

The Importance of Acromegaloid Physical Features for Clinical Practice

Acromegaly and gigantism are hormonal disorders which develop as a consequence of chronic growth hormone hypersecretion. The prefix pseudo- is used to describe a certain clinical condition without a clearly proven characteristic of pathophysiological mechanism and basic biochemical features; pseudoacromegaly or acromegaloidism match the definition from above. In this case reports, we will try to provide a concise overview of diagnostic evaluation of acromegaloid physical appearance, while discussing two cases of patients who have similar clinical acromegaloid features as the first sign of the disease but have completely different etiologic backgrounds of their acromegalic appearance. The first case is of a 57-year-old male who presented with a marked acral growth and coarse facial features, but the diagnosis of secondary amyloidosis caused by multiple myeloma was confirmed just after biopsy of tongue and buccal mucosa. The second case is that of a 63-year-old male with an acromegaloid appearance caused by ectopic secretion of GH secreting lung carcinoma. The early diagnosis of ectopic acromegaly and pseudoacromegaly is still a challenging process. The key task is to confirm the GH axis abnormalities and establish the underlying disease, as a crucial step for faster treatment and need to avoid unnecessary therapeutic procedures to decreased mortality and improved quality of life.

Comprehensive genetic testing approaches as the basis for personalized management of growth disturbances: current status and perspectives

The implementation of high-throughput and deep sequencing methods in routine genetic diagnostics has significantly improved the diagnostic yield in patient cohorts with growth disturbances and becomes increasingly important as the prerequisite of personalized medicine. They provide considerable chances to identify even rare and unexpected situations; nevertheless, we must be aware of their limitations. A simple genetic test in the beginning of a testing cascade might also help to identify the genetic cause of specific growth disorders. However, the clinical picture of genetically caused growth disturbance phenotypes can vary widely, and there is a broad clinical overlap between different growth disturbance disorders. As a consequence, the clinical diagnosis and therewith connected the decision on the appropriate genetic test is often a challenge. In fact, the clinician asking for genetic testing has to weigh different aspects in this decision process, including appropriateness (single gene test, stepwise procedure, comprehensive testing), turnaround time as the basis for rapid intervention, and economic considerations. Therefore, a frequent question in that context is 'what to test when'. In this review, we aim to review genetic testing strategies and their strengths and limitations and to raise awareness for the future implementation of interdisciplinary genome medicine in diagnoses, treatment, and counselling of growth disturbances.

Approach to the Patient With Pseudoacromegaly

Pseudoacromegaly encompasses a heterogeneous group of conditions in which patients have clinical features of acromegaly or gigantism, but no excess of GH or IGF-1. Acromegaloid physical features or accelerated growth in a patient may prompt referral to endocrinologists. Because pseudoacromegaly conditions are rare and heterogeneous, often with overlapping clinical features, the underlying diagnosis may be challenging to establish. As many of these have a genetic origin, such as pachydermoperiostosis, Sotos syndrome, Weaver syndrome, or Cantú syndrome, collaboration is key with clinical geneticists in the diagnosis of these patients. Although rare, awareness of these uncommon conditions and their characteristic features will help their timely recognition.

Gonadotropin Suppression for 7 Years After a Single Histrelin Implant for Precocious Puberty

Gonadotropin-releasing hormone analogues (GnRHas) are an effective treatment to address the compromise in height potential seen in patients with central precocious puberty. There is no evidence in the literature of a single GnRHa used for longer than 2 years before being removed or replaced. We describe a patient who was on continuous gonadotropin suppression for 7 years and despite this, achieved a height potential within 1 SD of mid-parental height. A boy aged 10 years 3 months presented to the endocrine clinic with signs of precocious puberty and advanced bone age. Initial laboratory values were a random luteinizing hormone (LH) level of 9.4 mIU/mL, follicle-stimulating hormone (FSH) 16.3 mIU/mL, dehydroepiandrosterone sulfate 127 mcg/dL, and testosterone 628 ng/dL. The patient was initially started on Lupron injections before transitioning to a histrelin implant. Follow-up laboratory results 5 months post-suppression showed pre-pubertal random LH 0.2 mIU/mL, FSH 0.1 mIU/mL, and testosterone 5 ng/dL. The patient was lost to follow-up and returned 5 years later presenting with gynecomastia and delayed bone age. He had continuous gonadotropin suppression with random LH 0.10 mIU/mL, FSH 0.16 mIU/mL, and testosterone 8 ng/dL. The histrelin implant was removed, and 4 months later, his random pubertal hormone levels were LH 5.6 mIU/mL, FSH 4.3 mIU/mL, and testosterone 506 ng/dL. The patient’s mid-parental height was 175.3 cm and his near final height was 170.6 cm, which is within 1 SD of his genetic potential. Further studies are needed to explore continuous gonadotropin hormone suppression with a single histrelin implant beyond 2 years.

The aetiology of extreme tall stature in a screened Finnish paediatric population

BACKGROUND

Extremely tall children (defined as height SDS (HSDS) ≥+3) are frequently referred to specialized healthcare for diagnostic work-up. However, no systematic studies focusing on such children currently exist. We investigated the aetiology, clinical features, and auxological clues indicative of syndromic tall stature in extremely tall children subject to population-wide growth monitoring and screening rules.

METHODS

Subjects with HSDS ≥+3 after three years of age born between 1990 and 2010 were identified from the Helsinki University Hospital district growth database. We comprehensively reviewed their medical records up to December 2020 and recorded underlying diagnoses, auxological data, and clinical features.

FINDINGS

We identified 424 subjects (214 girls and 210 boys) who fulfilled the inclusion criteria. Underlying growth disorder was diagnosed in 61 (14%) patients, in 36 (17%) girls and 25 (12%) boys, respectively (P=0•15). Secondary causes were diagnosed in 42 (10%) patients and the two most frequent secondary diagnoses, premature adrenarche, and central precocious puberty were more frequent in girls. Primary disorder, mainly Marfan or Sotos syndrome, was diagnosed in 19 (4%) patients. Molecular genetic studies were used as a part of diagnostic work-up in 120 subjects. However, array CGH or next-generation sequencing studies were seldom used. Idiopathic tall stature (ITS) was diagnosed in 363 (86%) subjects, and it was considered familial in two-thirds. Dysmorphic features or a neurodevelopmental disorder were recorded in 104 (29%) children with ITS. The probability of a monogenic primary growth disorder increased with the degree of tall stature and deviation from target height.

INTERPRETATION

A considerable proportion of extremely tall children have an underlying primary or secondary growth disorder, and their risk is associated with auxological parameters. Clinical features related to syndromic tall stature were surprisingly frequent in subjects with ITS, supporting the view that syndromic growth disorders with mild phenotypes may be underdiagnosed in extremely tall children. Our results lend support to comprehensive diagnostic work-up of extremely tall children.

FUNDING

Päivikki and Sakari Sohlberg Foundation, Foundation for Pediatric Research, and Helsinki University Hospital research grants.

Epiphysiodesis for the treatment of tall stature and leg length discrepancy

Painful orthopedic conditions associated with extreme tall stature and leg length discrepancy (LLD) include back pain and adopting bad posture. After failure of conservative treatment options, blocking of the growth plates (epiphysiodesis) around the knee emerged as gold standard in patients with tall stature and LLD in the growing skeleton. Surgical planning includes growth prediction and evaluation of bone age. Since growth prediction is associated with a certain potential error, adequate planning and timing of epiphysiodesis are the key for success of the treatment. LLD corrections up to 5 cm can be achieved, and predicted extreme tall stature can be limited. Percutaneous epiphysiodesis techniques are minimally invasive, safe and efficient methods with low complication rates. In general, a multidisciplinary approach should be pursued when treating children and adolescents with tall stature.

Anti-Müllerian hormone and letrozole levels in boys with constitutional delay of growth and puberty treated with letrozole or testosterone

STUDY QUESTION

Does treatment of constitutional delay of growth and puberty (CDGP) in boys with aromatase inhibitor letrozole (Lz) or conventional low-dose testosterone (T) have differing effects on developing seminiferous epithelium?

SUMMARY ANSWER

Anti-Müllerian hormone (AMH) declined similarly in both treatment groups, and the two Sertoli cell-derived markers (AMH and inhibin B (iB)) exhibited differing responses to changes in gonadotrophin milieu.

WHAT IS KNOWN ALREADY

Boys with CDGP may benefit from puberty-inducing medication. Peroral Lz activates gonadotrophin secretion, whereas intramuscular low-dose T may transiently suppress gonadotrophins and iB.

STUDY DESIGN, SIZE, DURATION

Sera of 28 boys with CDGP who participated in a randomised, controlled, open-label trial at four paediatric centres in Finland between August 2013 and January 2017 were analysed. The patients were randomly assigned to receive either Lz (2.5 mg/day) (n = 15) or T (1 mg/kg/month) (n = 13) for 6 months.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The 28 patients were at least 14 years of age, showed first signs of puberty, wanted medical attention for CDGP and were evaluated at 0, 3, 6 and 12 months of visits. AMH levels were measured with an electrochemiluminescence immunoassay and Lz levels with liquid chromatography coupled with tandem mass spectrometry.

MAIN RESULTS AND THE ROLE OF CHANCE

AMH levels decreased in both treatment groups during the 12-month follow-up (P < 0.0001). Between 0 and 3 months, the changes in gonadotrophin levels (increase in the Lz group, decrease in the T group) correlated strongly with the changes in levels of iB (FSH vs iB, r = 0.55, P = 0.002; LH vs iB, r = 0.72, P < 0.0001), but not with the changes in AMH (P = NS). At 12 months, AMH levels did not differ between the groups (P = NS). Serum Lz levels (range, 124-1262 nmol/L) were largely explained by the Lz dose per weight (at 3 months r = 0.62, P = 0.01; at 6 months r = 0.52, P = 0.05). Lz levels did not associate with changes in indices of hypothalamic-pituitary-gonadal axis activity or Sertoli cell markers (in all, P = NS).

LIMITATIONS, REASONS FOR CAUTION

The original trial was not blinded for practical reasons and included a limited number of participants.

WIDER IMPLICATIONS OF THE FINDINGS

In early puberty, treatment-induced gonadotrophin stimulus was unable to counteract the androgen-mediated decrease in AMH, while changes in iB levels were associated with changes in gonadotrophin levels. AMH decreased similarly in both groups during the treatment, reassuring safety of developing seminiferous epithelium in both treatment approaches. Since a fixed dose of Lz induced variable serum Lz levels with a desired puberty-promoting effect in all boys, more research is needed to aim at a minimal efficient dose per weight.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Academy of Finland, the Foundation for Pediatric Research, the Emil Aaltonen Foundation, Sigrid Juselius Foundation and Helsinki University Hospital Research Funds. The authors have nothing to disclose.

TRIAL REGISTRATION NUMBER

NCT01797718.

Appropriate Age for Height Control Treatment in Patients With Marfan Syndrome

OBJECTIVE

This study aimed to determine the most appropriate age for height control treatment in patients with Marfan syndrome (MFS).

MATERIALS AND METHODS

This retrospective study included patients with MFS who underwent height control treatment with estradiol valerate. The estrogen dose was increased according to the height change. The cut-off age for the maximum difference between the expected height and actual final height was evaluated.

RESULTS

Seventeen patients were included in this study. The difference between the height predicted by the growth curve and the final height (gcHtD) and that predicted by the bone age and the final height (baHtD) was the largest in the 10.5 years age group (p=0.0045 and p=0.0237, respectively). The gcHtD was 10.6 (10.2, 13.5) cm for patients aged ≤10.5 years, whereas it was 0.6 (-3.65, 5.85) cm for patients aged >10.5 years. The baHtD was 10.1 (7.31, 11.42) cm for patients aged ≤10.5 years, while it was 3.83 (0.84, 6.4) cm for patients aged >10.5 years. When height change was observed for a minimum of 6 months after completion of estrogen treatment, the average growth was 0.6 (0.2, 2.1) cm.

CONCLUSION

Initiating height control treatment before the age of 10.5 years is effective in female patients with MFS.

Etiology and Clinical Profile of Patients with Tall Stature: A Single-Center Experience

BACKGROUND

There is no published literature on the profile of patients with tall stature (TS) from India. This study aimed to evaluate the etiological and clinical profile of patients with TS referred to our hospital.

MATERIALS AND METHODS

We performed a retrospective review of records of patients referred to us for evaluation of TS (January 2007 to March 2020). Relevant clinical, anthropometric, biochemical, and radiological data at presentation were recorded, and the final diagnosis reviewed.

RESULTS

The study included 16 subjects (6 boys, 10 girls) with a mean age at presentation of 13.2 ± 3.6 years. Most subjects were pubertal (n = 10) and belonged to the overweight or obese category (n = 10). The mean height and height standard deviation score (SDS) were 172.3 ± 20.3 cm and 3.6 ± 1.5, respectively, while mean mid-parental height (MPH) and MPH SDS were 168.8 ± 8.8 cm and 1.2 ± 0.9, respectively. The etiological diagnoses were familial TS (n = 9), acrogigantism (n = 3), obesity-related TS (n = 2), constitutional advancement of growth (n = 1), and Marfan syndrome (n = 1). The mean height SDS in subjects with acrogigantism was 6.4 ± 1.2 compared to 3.0 ± 0.6 in those with other etiologies of TS. Only one girl with familial TS and significantly increased predicted adult height (+4.56 SDS) opted for sex steroid therapy.

CONCLUSION

Familial TS is the most common diagnosis among patients referred for evaluation to our hospital. One should consider the possibility of acrogigantism in patients with growth acceleration, extreme TS, and markedly increased gap between height SDS and MPH SDS. Most patients with familial TS require reassurance and sex steroid therapy should be reserved for highly selected cases.

Towards a Rational and Efficient Diagnostic Approach in Children Referred for Tall Stature and/or Accelerated Growth to the General Paediatrician

Tall stature and/or accelerated growth (TS/AG) in a child can be the result of a primary or secondary growth disorder, but more frequently no cause can be found (idiopathic TS). The conditions with the most important therapeutic implications are Klinefelter syndrome, Marfan syndrome and secondary growth disorders such as precocious puberty, hyperthyroidism and growth hormone excess. We propose a diagnostic flow chart offering a systematic approach to evaluate children referred for TS/AG to the general paediatrician. Based on the incidence, prevalence and clinical features of medical conditions associated with TS/AG, we identified relevant clues for primary and secondary growth disorders that may be obtained from the medical history, physical evaluation, growth analysis and additional laboratory and genetic testing. In addition to obtaining a diagnosis, a further goal is to predict adult height based on growth pattern, pubertal development and skeletal maturation. We speculate that an improved diagnostic approach in addition to expanding use of genetic testing may increase the diagnostic yield and lower the age at diagnosis of children with a pathologic cause of TS/AG.

Growth Disturbances in Childhood Cancer Survivors

Survival from childhood cancer has improved dramatically over the last few decades, resulting in an increased need to address the long-term follow-up and care of childhood cancer survivors. Appropriate linear growth is an important measure of health, with alterations of growth in children and short adult height in those who have completed growth serving as potential indicators of the sequelae of the underlying diagnosis or the cancer treatments. It is therefore critical that clinicians, particularly endocrinologists, be familiar with the patterns of altered growth which may be seen following diagnosis and treatment for childhood cancer. In this article, we will review the growth alterations seen in childhood cancer survivors, focusing on risk factors and considerations in evaluation and care.

The Evaluation and Treatment of Tall Stature in Preadolescent Girls: A Case Report

Families may approach primary care providers for advice and treatment for tall stature (height more than two standard deviations above the mean height for a given age) in pre-pubertal children. The following case report describes an 11-year-old girl who was referred to an endocrinology specialist for familial tall stature. Potential pathological causes for tall stature are reviewed. The assessment, management, and risks and benefits of treatment for this condition are described. Finally, the role of the pediatric nurse practitioner in caring for youth with this chief complaint is discussed.

Pseudoacromegaly

Individuals with acromegaloid physical appearance or tall stature may be referred to endocrinologists to exclude growth hormone (GH) excess. While some of these subjects could be healthy individuals with normal variants of growth or physical traits, others will have acromegaly or pituitary gigantism, which are, in general, straightforward diagnoses upon assessment of the GH/IGF-1 axis. However, some patients with physical features resembling acromegaly - usually affecting the face and extremities -, or gigantism - accelerated growth/tall stature - will have no abnormalities in the GH axis. This scenario is termed pseudoacromegaly, and its correct diagnosis can be challenging due to the rarity and variability of these conditions, as well as due to significant overlap in their characteristics. In this review we aim to provide a comprehensive overview of pseudoacromegaly conditions, highlighting their similarities and differences with acromegaly and pituitary gigantism, to aid physicians with the diagnosis of patients with pseudoacromegaly.

Tall Stature: A Challenge for Clinicians

Clinicians generally use the term "tall stature" to define a height more than two standard deviations above the mean for age and sex. In most cases, these subjects present with familial tall stature or a constitutional advance of growth which is diagnosed by excluding the other conditions associated with overgrowth. Nevertheless, it is necessary to be able to identify situations in which tall stature or an accelerated growth rate indicate an underlying disorder. A careful physical evaluation allows the classification of tall patients into two groups: those with a normal appearance and those with an abnormal appearance including disproportion or dysmorphism. In the first case, the growth rate has to be evaluated and, if it is normal for age and sex, the subjects may be considered as having familial tall stature or constitutional advance of growth or they may be obese, while if the growth rate is increased, pubertal status and thyroid function should be evaluated. In turn, tall subjects having an abnormal appearance can be divided into proportionate and disproportionate syndromic patients. Before initiating further investigations, the clinician needs to perform both a careful physical examination and growth evaluation. To exclude pathological conditions, the cause of tall stature needs to be considered, although most children are healthy and generally do not require treatment to inhibit growth progression. In particular cases, familial tall stature subject can be treated by inducing puberty early and leading to a complete fusion of the epiphyses, so final height is reached. This review aims to provide proposals about the management of tall children.

The causes and consequences of pituitary gigantism

In the general population, height is determined by a complex interplay between genetic and environmental factors. Pituitary gigantism is a rare but very important subgroup of patients with excessive height, as it has an identifiable and clinically treatable cause. The disease is caused by chronic growth hormone and insulin-like growth factor 1 secretion from a pituitary somatotrope adenoma that forms before the closure of the epiphyses. If not controlled effectively, this hormonal hypersecretion could lead to extremely elevated final adult height. The past 10 years have seen marked advances in the understanding of pituitary gigantism, including the identification of genetic causes in ~50% of cases, such as mutations in the AIP gene or chromosome Xq26.3 duplications in X-linked acrogigantism syndrome. Pituitary gigantism has a male preponderance, and patients usually have large pituitary adenomas. The large tumour size, together with the young age of patients and frequent resistance to medical therapy, makes the management of pituitary gigantism complex. Early diagnosis and rapid referral for effective therapy appear to improve outcomes in patients with pituitary gigantism; therefore, a high level of clinical suspicion and efficient use of diagnostic resources is key to controlling overgrowth and preventing patients from reaching very elevated final adult heights.

Klinefelter syndrome, insulin resistance, metabolic syndrome, and diabetes: review of literature and clinical perspectives

PURPOSE

Klinefelter syndrome (KS), the most frequent chromosomic abnormality in males, is associated with hypergonadotropic hypogonadism and an increased risk of cardiovascular diseases (CVD). The mechanisms involved in increasing risk of cardiovascular morbidity and mortality are not completely understood. This review summarises the current understandings of the complex relationship between KS, metabolic syndrome and cardiovascular risk in order to plan future studies and improve current strategies to reduce mortality in this high-risk population.

METHODS

We searched PubMed, Web of Science, and Scopus for manuscripts published prior to November 2017 using key words "Klinefelter syndrome" AND "insulin resistance" OR "metabolic syndrome" OR "diabetes mellitus" OR "cardiovascular disease" OR "testosterone". Manuscripts were collated, studied and carried forward for discussion where appropriate.

RESULTS

Insulin resistance, metabolic syndrome, and type 2 diabetes are more frequently diagnosed in KS than in the general population; however, the contribution of hypogonadism to metabolic derangement is highly controversial. Whether this dangerous combination of risk factors fully explains the CVD burden of KS patients remains unclear. In addition, testosterone replacement therapy only exerts a marginal action on the CVD system.

CONCLUSION

Since fat accumulation and distribution seem to play a relevant role in triggering metabolic abnormalities, an early diagnosis and a tailored intervention strategy with drugs aimed at targeting excessive visceral fat deposition appear necessary in patients with KS.

Decreased lymphocytes and increased risk for infection are common in endogenous pediatric Cushing syndrome

BackgroundHypercortisolemia results in changes of the immune system and elevated infection risk, but data on the WBC changes in pediatric Cushing syndrome (CS) are not known. We describe the changes of the WBC lineages in pediatric endogenous hypercortisolemia, their associations with the markers of disease severity, and the presence of infections.MethodsWe identified 197 children with endogenous CS. Clinical and biochemical data were recorded. Sixty-six children with similar age and gender, and normocortisolemia served as controls.ResultsThe absolute lymphocyte count of CS patients was significantly lower than that of controls, while the total WBC and the absolute neutrophil counts were significantly higher. These changes correlated with several markers of CS severity and improved after resolution of hypercortisolemia. Infections were identified in 35 patients (17.8%), and their presence correlated to elevated serum morning cortisol, midnight cortisol, and urinary free cortisol levels, as well as with the decrease in absolute lymphocyte count.ConclusionsChildren with endogenous CS have abnormal WBC counts, which correlate with the severity of CS, and normalize after cure. Infections are common in this population; clinicians should be aware of this complication of CS and have low threshold in diagnosis and treating infections in CS.

Pseudoacromegaly: A Differential Diagnostic Problem for Acromegaly With a Genetic Solution

Acromegaly is usually not a difficult condition to diagnose once the possibility of this disease has been raised. However, a few conditions present with some aspects of acromegaly or gigantism but without growth hormone (GH) excess. Such cases are described as "pseudoacromegaly" or "acromegaloidism". Here we describe a female patient investigated for GH excess at 10 years of age for tall stature since infancy (height and weight > +3 standard deviations) and typical acromegalic features, including large hands/feet, large jaw, tongue, hoarse deep voice, and headache. Results of radiography of the sella turcica and GH response at an oral glucose tolerance test and insulin–arginine– thyrotrophin–luteinizing hormone–releasing hormone test were normal. Ethinylestradiol and medroxyprogesterone were given for 2 years; this successfully stopped further height increase. Although the patient's growth rate plateaued, coarsening of the facial features and acral enlargement also led to investigations for suspicion of acromegaly at 23 and 36 years of age, both with negative results. On referral at the age of 49 years, she had weight gain, sweating, sleep apnea, headaches, joint pain, and enlarged tongue. Endocrine assessment again showing normal GH axis was followed by genetic testing with a macrocephaly/overgrowth syndrome panel. A denovo mutation in the NSD1 gene (c.6605G>C; p.Cys2202Ser) was demonstrated. Mutations affecting the same cysteine residue have been identified in patients with Sotos syndrome. In summary, Sotos syndrome and other overgrowth syndromes can mimic the clinical manifestations of acromegaly or gigantism. Genetic assessment could be helpful in these cases.