Severe Isolated Growth Hormone Deficiency Research Articles

Auxological, Clinical, and MRI Abnormalities in Pediatric Patients With Isolated Growth Hormone Deficiency.

This study aimed to assess the auxological, clinical, and MRI features of pediatric patients with isolated growth hormone deficiency (GHD) by analyzing the demographic and clinical characteristics of the study cohort. A cohort of 115 pediatric patients diagnosed with isolatedGHD was included. The patients were evaluated at a tertiary center in Jeddah, Saudi Arabia. Collected data included demographic information and auxological evaluations, such as height standard deviation (SD), height centile, weight SD, weight centile, and bone age SD. Neuroradiological assessments, particularly magnetic resonance imaging (MRI) of the hypothalamic-pituitary region, were collectedto identify any structural abnormalities contributing to GHD. A total of 67 (SD 58.3) were males. The mean age was 9.55 years (SD 3.45). The mean bone age was 7.37 years (SD 3.24), indicating delayed bone development. Height measurements reflected a significant growth impairment, with a mean height SD of -2.45 (SD 1.12). Out of the 115 pediatric patients in the study cohort, 84 (73%) underwent neuroradiological assessments using brain MRI. Among these, 12% were found to have MRI abnormalities. The prevalence of MRI abnormality in the subgroup with severe growth hormone deficiency was higher, reaching 21%. The peak growth hormone (GH) in the growth hormone stimulation test was 6.38 ng/mL (SD 3.24). There was a significant difference in the peak GH levels between the subgroup of patients with normal MRI findings (mean 6.02 ng/mL, SD 2.47) and those with abnormal MRI findings (mean 3.2 ng/mL, SD 2.8) (p=0.01). Children with isolated GHD exhibited significant growth impairment and clinical characteristics consistent with thedisorder. Neuroradiological abnormalities are common among patients with severe growth hormone deficiency; therefore, radiological assessment including MRI of the pituitary gland is recommended in patients with severe isolated growth hormone deficiency.

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

We aimed to describe the clinical characteristics of patients with congenital combined pituitary hormone deficiency (CPHD) and evaluate the first-year growth responses of individuals with CPHD and isolated growth hormone deficiency (IGHD) in order to establish the influence of other hormone deficiencies on growth response. This retrospective study was conducted in four tertiary care centers in Turkey. The records of patients diagnosed with CPHD (n=39) and severe IGHD (n=50) were collected. Cases with acquired lesions or chronic diseases were not included in the study. Data are presented as median (interquartile range). Among 39 patients (13 females; 33%) with a diagnosis of CPHD, the majority of patients (64%) presented initially with combined deficits at baseline examination, whereas isolated deficiencies (36%) were less prevalent. Among all patients with GH deficiency, TSH, ACTH, FSH/LH, and ADH deficiencies were present in 94%, 74%, 44%, and 9% of patients, respectively. Patients with CPHD were diagnosed at a younger age (4.9 (8.4) vs. 11.6 (4.1), p<0.001, respectively) and had lower peak GH concentrations (0.4 (1.8) vs. 3.7 (2.9), p<0.001, respectively) than patients with IGHD. Patients with IGHD and CPHD had similar first-year growth responses (Δheight SD score of 0.55 (0.63) vs. 0.76 (0.71), respectively, p=0.45). We established the nature and timing of numerous hormonal deficits emerging over time. We also identified that the existence of CPHD did not hinder growth response.

Dental arches in inherited severe isolated growth hormone deficiency

ObjectivesThe growth of the dental arches depends on GH and insulin-like growth factor type 1 (IGF1), but the consequences of GH deficiency (GHD) on their growth are still unclear, probably due to the acquired etiology of GHD in most described series, often associated with additional pituitary deficits (thyrotrophic, corticotrophic and gonadotrophic hormones), and imperfections of related replacement therapies, which may affect the dental arch growth. To avoid these limitations, we took advantage of a unique cohort of subjects with isolated GH deficiency (IGHD) due the same mutation in the GH releasing hormone receptor gene, living with very low serum GH and low to undetectable circulating IGF1 levels. Our purpose was to analyze the dimensions of maxillary and mandibular dental arches. Methods22 adult IGHD (15 untreated and 7 previously partially treated with GH) and 33 controls were enrolled in a cross-sectional study using the Ortho Insight 3D and MeshMixer software, ResultsIn untreated IGHD subjects all maxillary arch measures were smaller than controls, while among mandibular arches, only the mandibular canine width and the mandibular arch length were reduced. In partially GH treated subjects only the palate depth, the maxillary canine width, the maxillary and mandibular arch lengths remained smaller than controls. ConclusionsIGHD reduces the growth of maxillary arch to a greater degree than the mandibular arch, suggesting different control of superior and inferior dental arches. GH treatment increases some of these measures.

Allelic Variants in Established Hypopituitarism Genes Expand Our Knowledge of the Phenotypic Spectrum.

We report four allelic variants (three novel) in three genes previously established as causal for hypopituitarism or related disorders. A novel homozygous variant in the growth hormone gene, GH1 c.171delT (p.Phe 57Leufs*43), was found in a male patient with severe isolated growth hormone deficiency (IGHD) born to consanguineous parents. A hemizygous SOX3 allelic variant (p.Met304Ile) was found in a male patient with IGHD and hypoplastic anterior pituitary. YASARA, a tool to evaluate protein stability, suggests that p.Met304Ile destabilizes the SOX3 protein (ΔΔG = 2.49 kcal/mol). A rare, heterozygous missense variant in the TALE homeobox protein gene, TGIF1 (c.268C>T:p.Arg90Cys) was found in a patient with combined pituitary hormone deficiency (CPHD), diabetes insipidus, and syndromic features of holoprosencephaly (HPE). This variant was previously reported in a patient with severe holoprosencephaly and shown to affect TGIF1 function. A novel heterozygous TGIF1 variant (c.82T>C:p.Ser28Pro) was identified in a patient with CPHD, pituitary aplasia and ectopic posterior lobe. Both TGIF1 variants have an autosomal dominant pattern of inheritance with incomplete penetrance. In conclusion, we have found allelic variants in three genes in hypopituitarism patients. We discuss these variants and associated patient phenotypes in relation to previously reported variants in these genes, expanding our knowledge of the phenotypic spectrum in patient populations.

Disruption of the GHRH receptor and its impact on children and adults: The Itabaianinha syndrome.

Since 1994, we have been studying an extended kindred with 105 subjects (over 8 generations) residing in Itabaianinha County, in the Brazilian state of Sergipe, who have severe isolated GH deficiency (IGHD) due to a homozygous inactivating mutation (c.57 + 1G > A) in the GH releasing hormone (GHRH) receptor (GHRHR) gene. Most of these individuals have never received GH replacement therapy. They have low GH, and very low and often undetectable levels of serum IGF-I. Their principal physical findings are proportionate short stature, doll facies, high-pitched-voice, central obesity, wrinkled skin, and youthful hair with delayed pigmentation, and virtual absence of graying. The newborns from this cohort are of normal size, indicating that GH is not needed for intra-uterine growth. However, these IGHD individuals exhibit a myriad of phenotypic changes throughout the body, with a greater number of beneficial than harmful consequences. This GHRH signal disruption syndrome has been a valuable model to study the GH roles in body size and function. This reviews summarized the findings we have reported on this cohort.

SUN-067 Pituitary Dysfunction in Children with Ectopic Posterior Pituitary

Background: Imaging studies aid in the detection of structural abnormalities that may be associated with pituitary dysfunction, such as ectopic posterior pituitary (EPP). The location of the ectopic lobe can vary, but it is most commonly located along the median eminence in the floor of the third ventricle. An EPP could result from complete or partial defective neural migration during embryogenesis, which could explain the different loci of EPP. Affected individuals have either severe isolated growth hormone deficiency (IGHD) or combined pituitary hormone deficiencies (CPHD); diabetes insipidus is not a feature, indicating that the EPP is functioning normally. Aim: To detect the prevalence of IGHD or CPHD in children with EPP. In addition, to evaluate the association between the location of EPP and pituitary dysfunction. Methods: A retrospective chart review of MRI reports at St. Christopher’s Hospital for Children (SCHC) from 2006-2018 that were found to have EPP. Pituitary hormone function was evaluated in the majority of the patient population. Results: Of the 26 patients with EPP, [16 males (M) and 10 females (F)], mean chronologic age was 5.98+5.18 yrs, only 20 patients had an endocrine evaluation at SCHC. Of the 20 children, 14 had CPHD and 4 had IGHD.Patients were classified into 3 groups (upper, middle & lower) according to EPP location along the pituitary stalk. Of the 21 patients with upper EPP, 17 had pituitary dysfunction (14 with CPHD, 3 with IGHD). Of the 4 children with middle EPP, only 1 had pituitary dysfunction which was IGHD. One patient had lower EPP with hyperprolactinemia. Diabetes insipidus was not identified in any of the children. Conclusion: Our study supports previous reports that CPHD and IGHD are frequent in patients with EPP. Similarly, our data further demonstrate that no cases of diabetes insipidus have been reported in children with EPP.In our study, EPP is most commonly located along the upper third of pituitary stalk at the median eminence level, with a higher prevalence of CPHD and IGHD, a finding similar to prior studies. No CPHD was reported in middle/lower but IGHD was found in the middle EPP group.

Vestibular function in severe GH deficiency due to an inactivating mutation in the GH-releasing hormone receptor gene.

Body balance involves the vestibular, visual, and proprioceptive systems. IGF-I is a GH-dependent key factor in the development and postnatal differentiation of the inner ear in mice and men, but its role in the vestibular function in adult humans is unknown. We have previously described a cohort of individuals with severe isolated GH deficiency (IGHD) caused by a mutation in the GHRH receptor (GHRHR) gene. These individuals complain of dizziness, exhibit mild sensorineural loss, but have normal postural balance, without increase in falls risk. The aim of this study was to evaluate their vestibular function. We performed physical examination (clinical head impulse and Fukuda dynamic stepping test), oculomotor (saccadic eye movements, spontaneous, semi-spontaneous and opotokinetic nystagmus, and pendular tracking) and caloric stimulation (postcaloric reflex and ocular fixation index) tests, in 15 GH-naïve IGHD (seven males) and 15 controls (five males). IGHD subjects showed lower height and weight, with similar BMI to controls, and higher number of individuals with abnormal clinical head impulse test and abnormal oculomotor tests, namely the saccadic movements and the spontaneous nystagmus. There was a nonsignificant trend in abnormalities in the Fukuda stepping test and postcaloric reflex test. Adult untreated IGHD individuals have higher prevalence of moderate peripheral vestibular impairment, and of abnormal vestibular-ocular reflex.

Adult individuals with congenital, untreated, severe isolated growth hormone deficiency have satisfactory muscular function.

While growth hormone (GH) and the insulin-like growth factor type I (IGF-I) are known to exert synergistic actions on muscle anabolism, the consequences of prolonged GH deficiency (GHD) on muscle function have not been well defined. We have previously described a large cohort of subjects with isolated GHD (IGHD) caused by a mutation in the GH-releasing hormone receptor gene, with low serum levels of GH and IGF-I. The aim of this study was to assess muscular function in these IGHD subjects. A total of 31 GH-naïve IGHD (16 males) and 40 control (20 males) subjects, matched by age and degree of daily physical activity, were enrolled. Fat free mass was measured by bioelectrical impedance; muscle strength by dynamometry of handgrip, trunk extension, and knee extension; myoelectric activity and muscle fatigue by fractal dimension; conduction velocity in vastus medialis, rectus femoris, and vastus lateralis muscles by surface electromyography. The IGHD group showed higher knee extension strength both when corrected for weight and fat free mass, and higher handgrip and trunk extension strength corrected by fat free mass. They also exhibit higher conduction velocity of the muscles vastus medialis, rectus femoris, and vastus lateralis, but lower free fat mass and myoelectric activity of the vastus medialis, rectus femoris and vastus lateralis. There were no differences between the two groups in fractal dimension in all studied muscles. Individuals with untreated IGHD have better muscle strength parameters adjusted for weight and fat free mass than controls. They also exhibit greater peripheral resistance to fatigue, demonstrating satisfactory muscle function.

Genetic Mutations in the GH/IGF Axis.

The GH/IGF axis plays an important role in the control of pre and postnatal growth. At least 48 monogenic defects have been described affecting the production, secretion, and action of GH and IGFs. Molecular defects of the GH/IGF axis resulting in short stature were arbitrarily classified into 4 groups: 1. Combined pituitary hormone deficiency (CPHD) (a. syndromic CPHD and b. non-syndromic CPHD), 2. Isolated GH deficiency (IGHD), 3. GH insensitivity, and 4. IGF-I insensitivity. Genetic diagnosis is obtained in about 30-40% of children with growth retardation, severe IGHD, CPHD, apparent GH or IGF-I insensitivity, and small for gestational age. Increased accessibility to next generation sequencing (NGS) techniques resulted in a significant number of likely pathogenic variants in genes previously associated with short stature as well as in completely novel genes. Functional in vitro assays and in vivo animal models are required to determine the real contribution of these findings.

Occurrence of neoplasms in individuals with congenital, severe GH deficiency from the Itabaianinha kindred

Growth hormone (GH) and the insulin-like growth factor I (IGF-I) have cell proliferative and differentiation properties. Whether these hormones have a role in mutagenesis is unknown. Nevertheless, severe IGF-I deficiency seems to confer protection against the development of neoplasms. Here, we report five cases of adult patients with severe and congenital isolated GH deficiency (IGHD) due to the c.57+1G>A mutation in the GHRH receptor gene, who developed tumors. Four GH-naïve subjects presented skin tumors: a 42-year-old man with a fibroepithelial polyp, a 53-year-old woman and two men (59 and 56 years old) with epidermoid skin cancers. One of these died from it after three surgeries and radiotherapy. The fifth patient was a 25-year-old woman, who had intermittently received GH replacement therapy (GHRT) from age 11 to 18, who developed an ependymoma extending from the fourth ventricle to the end of the thoracic spine. She underwent three surgical procedures, without obvious evidence of tumor recurrence during the six years follow up. These observations suggest that severe IGHD does not protect completely from development of tumors.

Partial Loss of Function of the GHRH Receptor Leads to Mild Growth Hormone Deficiency.

Recessive mutations in GHRHR are associated with severe isolated growth hormone deficiency (IGHD), with a final height in untreated patients of 130 cm ± 10 cm (-7.2 ± 1.6 SDS; males) and 114 ± 0.7 cm (-8.3 ± 0.1 SDS; females). We hypothesized that a consanguineous Pakistani family with IGHD in three siblings (two males, one female) would have mutations in GH1 or GHRHR. Two novel homozygous missense variants [c.11G>A (p.R4Q), c.236C>T (p.P79L)] at conserved residues were identified in all three siblings. Both were absent from control databases, aside from pR4Q appearing once in heterozygous form in the Exome Aggregation Consortium Browser. The brothers were diagnosed with GH deficiency at 9.8 and 6.0 years (height SDS: -2.24 and -1.23, respectively), with a peak GH of 2.9 μg/liter with low IGF-1/IGF binding protein 3. Their sister presented at 16 years with classic GH deficiency (peak GH <0.1 μg/liter, IGF-1 <3.3 mmol/liter) and attained an untreated near-adult height of 144 cm (-3.0 SDS); the tallest untreated patient with GHRHR mutations reported. An unrelated Pakistani female IGHD patient was also compound homozygous. All patients had a small anterior pituitary on magnetic resonance imaging. Functional analysis revealed a 50% reduction in maximal cAMP response to stimulation with GHRH by the p.R4Q/p.P79L double mutant receptor, with a 100-fold increase in EC50. We report the first coexistence of two novel compound homozygous GHRHR variants in two unrelated pedigrees associated with a partial loss of function. Surprisingly, the patients have a relatively mild IGHD phenotype. Analysis revealed that the pP79L mutation is associated with the compromise in function, with the residual partial activity explaining the mild phenotype.

Development of additional pituitary hormone deficiencies in pediatric patients originally diagnosed with isolated growth hormone deficiency due to organic causes

To determine characteristics of children initially diagnosed with isolated growth hormone deficiency (IGHD) of organic aetiology, who later developed multiple pituitary hormone deficiencies (MPHD). Data were analysed for 716 growth hormone-treated children with organic IGHD, who were growth hormone-naïve at baseline in the multinational, observational Genetics and Neuroendocrinology of Short Stature International Study. Development of MPHD was ascertained from investigator-provided diagnoses, adverse events and concomitant medications. Analyses were performed for all patients and separately for those who developed MPHD within 4.5 years or had >3.5 years follow-up and continued to have IGHD (4-year cohort). MPHD developed in 71/716 (9.9%) children overall, and in 60/290 (20.7%) in the 4-year cohort. The most frequent additional deficiencies were thyroid-stimulating hormone (47 patients) and gonadotropins (23 patients). Compared with those who remained with IGHD, children who developed MPHD had more severe GHD at study entry, significantly lower baseline insulin-like growth factor1, peak stimulated growth hormone, and more frequent diagnosis of intracranial tumour or mutation of gene(s) controlling hypothalamic-pituitary development and/or function. Multivariate logistic regression analyses identified female gender, longer follow-up, higher baseline age and lower peak stimulated growth hormone as predictors of MPHD development. MPHD is more likely to develop in patients with severe organic IGHD, especially those with history of intracranial tumour or mutation of gene(s) controlling hypothalamic-pituitary development and/or function. Older baseline age, female gender and longer follow-up duration were also associated with higher incidence of MPHD. Long-term monitoring of pituitary function is recommended, irrespective of the aetiology of GHD.

Brazilian adult individuals with untreated isolated GH deficiency do not have accelerated subclinical atherosclerosis.

GH and its principal mediator IGF1 have important effects on metabolic and cardiovascular (CV) status. While acquired GH deficiency (GHD) is often associated with increased CV risk, the consequences of congenital GHD are not known. We have described a large group of patients with isolated GHD (IGHD) due to a homozygous mutation (c.57+1G>A) in the GH releasing hormone receptor gene, and shown that adult GH-naïve individuals have no evidence of clinically evident premature atherosclerosis. To test whether subclinical atherosclerosis is anticipated in untreated IGHD, we performed a cross-sectional study of 25 IGHD and 27 adult controls matched for age and gender. A comprehensive clinical and biochemical panel and coronary artery calcium scores were evaluated by multi-detector tomography. Height, weight, IGF1, homeostasis model assessment of insulin resistance, creatinine and creatininekinase were lower in the IGHD group. Median and interquartile range of calcium scores distribution was similar in the two groups: IGHD 0(0) and control 0(4.9). The vast majority of the calcium scores (20 of 25 IGHD (80%) and 18 of 27 controls (66.6%)) were equal to zero (difference not significant). There was no difference in the calcium scores classification. None of IGHD subjects had minimal calcification, which were present in four controls. Three IGHD and four controls had mild calcification. There were two IGHD individuals with moderate calcification and one control with severe calcification. Our study provides evidence that subjects with congenital isolated lifetime and untreated severe IGHD do not have accelerated subclinical coronary atherosclerosis.

Voice Formants in Individuals With Congenital, Isolated, Lifetime Growth Hormone Deficiency

To analyze the voice formants (F1, F2, F3, and F4 in Hz) of seven oral vowels, in Brazilian Portuguese, [a, ε, e, i, ɔ, o, and u] in adult individuals with congenital lifetime untreated isolated growth hormone deficiency (IGHD). This is a cross-sectional study. Acoustic analysis of isolated vowels was performed in 33 individuals with IGHD, age 44.5 (17.6) years (16 women), and 29 controls, age 51.1 (17.6) years (15 women). Compared with controls, IGHD men showed higher values of F3 [i, e, and ε], P=0.006, P=0.022, and P=0.006, respectively and F4 [i], P=0.001 and lower values of F2 [u], P=0.034; IGHD women presented higher values of F1 [i and e] P=0.029 and P=0.036; F2 [ɔ] P=0.006; F4 [ɔ] P=0.031 and lower values of F2 [i] P=0.004. IGHD abolished most of the gender differences in formant frequencies present in controls. Congenital, severe IGHD results in higher values of most formant frequencies, suggesting smaller oral and pharyngeal cavities. In addition, it causes a reduction in the effect of gender on the structure of the formants, maintaining a prepubertal acoustic prediction.

Autosomal recessive form of isolated growth hormone deficiency is more frequent than the autosomal dominant form in a Brazilian cohort

BackgroundIn most studies, the autosomal dominant (type II) form of isolated growth hormone deficiency (IGHD) has been more frequent than the autosomal recessive (type I) form.Our aim was to assess defects in the GH1 in short Brazilian children with different GH secretion status. Subjects and methodsWe selected 135 children with postnatal short stature and classified according to the highest GH peak at stimulation tests in: severe IGHD (peak GH≤3.3μg/L, n=38, all with normal pituitary magnetic resonance imaging); GH peak between 3.3 and 10μg/L (n=76); and GH peak >10μg/L (n=21). The entire coding region of GH1 was sequenced and complete GH1 deletions were assessed by Multiplex Ligation Dependent Probe Amplification and restriction enzyme digestion. ResultsPatients with severe IGHD had a higher frequency of consanguinity, were shorter, had lower levels of IGF-1 and IGFBP-3, and despite treatment with lower GH doses had a greater growth response than patients with GH peak ≥3.3μg/L. Mutations were found only in patients with severe IGHD (GH peak<3.3μg/L). Eight patients had autosomal recessive IGHD: Seven patients were homozygous for GH1 deletions and one patient was compound heterozygous for a GH1 deletion and the novel c.171+5G>C point mutation in intron 2, predicted to abolish the donor splice site. Only one patient, who was heterozygous for the c.291+1G>T mutation located at the universal donor splice site of intron 3 and predicts exon 3 skipping, had an autosomal dominant form. ConclusionAnalysis of GH1 in a cohort of Brazilian patients revealed that the autosomal recessive form of IGHD was more common than the dominant one, and both were found only in severe IGHD.

Changes in circadian rhythm of prolactin in short children are dependent on growth hormone secretion.

Taking into consideration the common ontogenic origin of prolactin (Prl) and growth hormone (GH), the Prl circadian pattern was analysed in children with different degrees of GH deficiency (GHD). The analysis comprised 100 short children (31 girls and 69 boys), aged: 10.1±3.51 years. Based on maximal GH secretion (GHmax) during two stimulating tests multiple hormone deficiency (MPHD), severe isolated GHD (SIGHD), partial isolated GHD (PIGHD) or idiopathic short stature (ISS) were diagnosed. Non-inferential chronobiometry (macroscopic analysis) of the circadian Prl rhythm, based on serum Prl measured every 3 hours during 24 hours, was performed. In this analysis, mesor, the area under curve (AUC), peak and trough level, dispersion, mean nocturnal and diurnal concentration, night/day ratio, amplitude and regression index were estimated. In the study group, the positive correlations between GHmax and Prl concentrations at 02:00 and at 05:00 were observed, as well as between GHmax and mesor, amplitude, mean nocturnal concentration, night/day ratio and AUC. The nocturnal rise of Prl secretion was blunted in 100% MPHD and 50% SIGHD children, whereas in most children with PIGHD and ISS, the circadian Prl rhythm was normal. 1) In short children, the lower the concentration of GH is, the more blunted nocturnal Prl secretion becomes. 2) In the majority of MPHD and SIGHD children (but not PIGHD), the circadian Prl rhythm was disturbed; namely, reduced nocturnal Prl secretion was noticeable.

Defective minor spliceosome mRNA processing results in isolated familial growth hormone deficiency

The molecular basis of a significant number of cases of isolated growth hormone deficiency remains unknown. We describe three sisters affected with severe isolated growth hormone deficiency and pituitary hypoplasia caused by biallelic mutations in the RNPC3 gene, which codes for a minor spliceosome protein required for U11/U12 small nuclear ribonucleoprotein (snRNP) formation and splicing of U12-type introns. We found anomalies in U11/U12 di-snRNP formation and in splicing of multiple U12-type introns in patient cells. Defective transcripts include preprohormone convertases SPCS2 and SPCS3 and actin-related ARPC5L genes, which are candidates for the somatotroph-restricted dysfunction. The reported novel mechanism for familial growth hormone deficiency demonstrates that general mRNA processing defects of the minor spliceosome can lead to very narrow tissue-specific consequences.Subject Categories Genetics, Gene Therapy ' Genetic Disease; Metabolism

Relatively high frequency of non‐synonymous GLI2 variants in patients with congenital hypopituitarism without holoprosencephaly

GLI2 is a downstream transcription factor in Sonic Hedgehog signalling, acting early in ventral forebrain and pituitary development. Heterozygous nonsense GLI2 mutations have been reported in patients with isolated or combined pituitary hormone deficiency (CPHD), with or without holoprosencephaly. The aim of this study was to screen for GLI2 mutations in a large cohort of patients with congenital GH deficiency. The GLI2 coding region of 41 patients with severe isolated GH deficiency (IGHD) and 136 patients with CPHD was amplified by PCR using intronic primers and sequenced. The frequency of GLI2 variants was verified in up to 155 Brazilian controls and in the 1000 Genomes database. The consequences of allelic variants were analysed by the Polyphen, SIFT, Mutationtaster and SNAP prediction sites. Eighteen different heterozygous non-synonymous GLI2 variants were identified in 24 patients. Twenty-three patients had CPHD and one had IGHD. Two patients had additional diabetes insipidus, indicating deficiencies of anterior and posterior pituitary lobes. The posterior pituitary lobe on MRI was ectopic in 16, not visible in 4, normally placed in 2 and imaging was not available in two patients, but there were no signs of holoprosencephaly. Sixteen GLI2 variants were considered deleterious in at least one of the prediction sites. A relatively high frequency of non-synonymous GLI2 variants was identified in patients with congenital GH deficiency without other brain defects, and most of these patients presented with CPHD and an ectopic posterior pituitary lobe. In vitro functional assays may contribute to ascertain the deleterious consequences of these variants.

Association of the (CA)n repeat polymorphism of insulin-like growth factor-I and −202 A/C IGF-binding protein-3 promoter polymorphism with adult height in patients with severe growth hormone deficiency

A number of mathematical models for predicting growth and final height outcome have been proposed to enable the clinician to 'individualize' growth-promoting treatment. However, despite optimizing these models, many patients with isolated growth hormone deficiency (IGHD) do not reach their target height. The aim of this study was to analyse the impact of polymorphic genotypes [CA repeat promoter polymorphism of insulin-like growth factor-I (IGF-I) and the -202 A/C promoter polymorphism of IGF-Binding Protein-3 (IGFBP-3)] on variable growth factors as well as final height in severe IGHD following GH treatment. DESIGN, PATIENTS AND CONTROLS: One hundred seventy eight (IGF-I) and 167 (IGFBP-3) subjects with severe growth retardation because of IGHD were studied. In addition, the various genotypes were also studied in a healthy control group of 211 subjects. The frequency of the individual IGF-I (CA)(n) repeats ranging from 10 to 24, with the most frequent allele containing CA(19), was similar in controls and in IGHD subjects. However, in controls, the pooled CA(19) and CA(20) as well as -202 A IGFBP-3 alleles were significantly (P < 0·01 and P < 0·001) more common in the taller [≥2 to 0 standard deviation score (SDS)] when compared with the shorter subgroup (<0 to ≤-2 SDS). Overall, the effect of recombinant human growth hormone (rhGH) replacement did not reveal any difference between the various genotypes in terms of final height. Independent of their genotype, all subjects showed a slightly lower adult height SDS compared with midparental height SDS. Our results indicate that in patients with severe IGHD, although the various IGF-I and IGFBP-3 genotypes may play a role in GH responsiveness, there was no effect on final height.

Arrest of atherosclerosis progression after interruption of GH replacement in adults with congenital isolated GH deficiency

GH replacement therapy (GHRT) in adult-onset GH deficiency (AOGHD) reduces carotid intima-media thickness (IMT) and increases myocardial mass, with improvement of systolic and diastolic function. These observations have reinforced the use of GHRT on AOGHD. Conversely, we have previously reported that in adults with lifetime congenital and severe isolated GH deficiency (IGHD) due to a mutation in GHRH receptor gene (GHRHR), a 6-month treatment with depot GH increased carotid IMT, caused the development of atherosclerotic plaques, and an increase in left ventricular mass index (LVMI), posterior wall, and septal thickness and ejection fraction. Such effects persisted 12 months after treatment (12-month washout - 12 mo). We have studied the cardiovascular status (by echocardiography and carotid ultrasonography) of these subjects 60 months after completion of therapy (60-month washout - 60 mo). Carotid IMT reduced significantly from 12 to 60 mo, returning to baseline (pre-therapy) value. The number of individuals with plaques was similar at 12 and 60 mo, remaining higher than pre-therapy. LVMI, relative posterior wall thickness, and septum thickness did not change between 12 and 60 mo, but absolute posterior wall increased from 12 to 60 mo. Systolic function, evaluated by ejection fraction and shortening fraction, was reduced at 60 mo in comparison with 12 mo returning to baseline levels. The E/A wave ratio (expression of diastolic function) decreased at 60 mo compared with both 12 mo and baseline. In adults with lifetime congenital IGHD, the increase in carotid IMT elicited by GHRT was transitory and returned to baseline 5 years after therapy discontinuation. Despite this, the number of subjects with plaques remained stable at 60 mo and higher than at baseline.