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C. RONGEN-WESTERLAKEN, S.L.S. DROP and J.N. VAN DEN ANKER

SUMMARY

Seven patients with primary glucocorticoid or glucocorticoid and mineralocorticoid deficiency are described with emphasis on the clinical presentation and laboratory investigations. Two patients presented with irreversible shock and at autopsy adrenal tissue was recognized only microscopically. In 3 patients adrenal antibodies were present. One girl had the polyglandular autoimmune disorder type I and one boy had glucocorticoid deficiency only. The histories of the patients illustrate that the presenting symptoms of primary adrenocortical insufficiency are very insiduous and that it may take several years before the correct diagnosis is made and hydrocortisone substitution therapy is instituted.

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Stenvert L. S. Drop, Guy Valiquette, Harvey J. Guyda, Maité T. Corvol and Barry I. Posner

ABSTRACT

An insulin radioreceptor assay (INS-RRA) and an insulin-like activity radioreceptor assay (ILAs-RRA) have been utilized to partially purify and characterize a protein from human amniotic fluid with ILAs-RRA reactivity. An acid-ethanol soluble protein with an apparent molecular weight of 34 500 daltons by calibrated Sephadex chromatography and an isoelectric point (pI) of 4.7 accounts for all of the ILAs-RRA reactivity present in human amniotic fluid. Since this protein has been found to be a binding protein for ILAs. but not for insulin, it has been termed amniotic fluid binding protein or AFBP. AFBP is reactive in a non-parallel manner in the ILAs-RRA and totally inactive in the INS-RRA. The activity of AFBP in the ILAs-RRA is thus to the competition of AFBP with the placental membrane receptor for the [125I]ILAs tracer employed in the ILAs-RRA.

AFBP inhibits the activity of added ILAs, but not of added insulin, in the INS-RRA, presumably by binding ILAs, while being inactive itself. In two biological assays studied to date, the rat epididymal fat pad assay and the rabbit chondrocyte sulphation assay, AFBP also inhibits the activity of added ILAs. These observations raise the possibility that binding protein(s) for insulin-like peptides may function as inhibitors of their bioactivity in different physiologic and pathologic states. The relation of AFBP to binding protein(s) in human plasma remains to be clarified.

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R Rosato, D Lindenbergh-Kortleve, J Neck, S Drop and G Jahn

OBJECTIVE: Hyperthyroidism in rats produces organ hypertrophy and increases in circulating IGF-I and IGF-binding protein (IGFBP)-3. Chronic treatment with thyroxine (T(4)) during pregnancy advances parturition, blocks lactation and changes several hormone receptors in mammary gland and liver. Since IGFs are implicated in mammary and liver growth and in differentiation, we studied the effects of hyperthyroidism, induced by daily injections of T(4) (0.25 mg/kg). DESIGN AND METHODS: Using quantitative RT-PCR and in situ hybridization, the gene expression of IGF-I, IGF-II and the IGFBPs was determined in mammary gland and liver of rats at estrus and days 7, 14 and 21 of pregnancy (G7, G14, G21), day 1 postpartum (L1) and 3 days after removing the litter (L4). Circulating levels of IGF-I, tri-iodothyronine (T(3)), PRL and GH were measured. RESULTS: T(4) treatment (HT) increased circulating T(3) save on G21, did not change serum IGF-I, increased PRL on G21 and decreased GH on L1. PRL decreased on L1 because of the absence of lactation. Hepatic IGF-I mRNA was low during pregnancy and increased on L4. HT advanced this increase to L1. In controls, liver IGFBP-3 mRNA levels decreased from G14 to G21, whereas IGFBP-4 showed an inverse pattern. HT lowered IGFBP-3 mRNA and increased IGFBP-4. Increases in mammary concentrations of IGF-I, IGFBP-3 and IGFBP-4 mRNAs were seen on G21. HT delayed these peaks to L1. Mammary IGF-II and IGFBP-2 mRNA levels were high on G7 and G14, and fell afterwards, with HT having no effects. IGFBP-5 mRNA decreased during pregnancy and increased on L1. HT increased IGFBP-5 levels in early pregnancy and on L1. IGF-I mRNA localized to connective and epithelial mammary tissue, while IGFBP-2 and IGFBP-5 mRNA was only in epithelial cells. CONCLUSION: These results imply a role for IGF-I, IGFBP-3 and IGFBP-4 in terminal mammary development, while IGF-II and IGFBP-2 may be implicated in early growth. IGFBP-5 has been implicated in mammary apoptosis, and the HT-induced increase may play a role in the premature mammary involution of the HT rats.

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J. Ballard, R. Baxter, M. Binoux, D. Clemmons, S. Drop, K. Hall, R. Hintz, M. Rechler, E. Rutanen and J. Schwander

The insulin-like growth factor (IGF) I and II circulate in plasma complexed to carrier on binding proteins.

On the basis of their chromatographically determined molecular size they have been designated 150–200 kD and 30–40 kD IGF binding proteins (BP). In recent years a growing number of proteins with IGF binding characteristics have been isolated from various body fluids, cell lines, and in various species. Provisional terminology based on source, species or molecular size has become increasingly confusing.

Thus far three distinct binding proteins have been fully characterized and their amino acid sequence determined (1–9).

During a workshop in the IGF binding proteins held in Vancouver, June 17–19, 1989, a proposal was put forward to adopt the designation 'IGFBP', with the addition of an arabic numeral and letter prefix to indicate species specificity as outlined in the following table.

It should be stressed that until full amino acid nucleotide sequence data

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S. L. S. Drop, I. M. E. Frohn-Mulder, H. K. A. Visser, W. G. Sippell, H. G. Dörr and M. Schöneshöfer

Abstract.

In two children with isolated congential hyperreninaemic hypoaldosteronism, as well as in their relatives, plasma levels of aldosterone (Aldo), corticosterone (B), deoxycorticosterone (DOC), 18-OH-B and 18-OH-DOC were measured before and after an iv bolus of 0.25 mg Synacthen® (Ciba). A corticosterone methyl oxidase deficiency type II was demonstrated in one child. Her normoreninaemic parents (no consanguinity) had plasma values consistent with heterozygosity. The results in the other child and one asymptomatic sib were compatible with a partial corticosterone methyl oxidase deficiency type I. His parents were consanguine but had normal Aldo levels. Overnight dexamethasone administration did not suppress any of the steroids measured except cortisol, suggesting synthesis of these steroids by the zona glomerulosa.

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M Cools, P Hoebeke, K P Wolffenbuttel, H Stoop, R Hersmus, M Barbaro, A Wedell, H Brüggenwirth, L H J Looijenga and S L S Drop

Objective

Most patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth.

Design and methods

Clinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function.

Results

LH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenotype. In the girl, gonadectomy at 13 years revealed incomplete spermatogenesis and bilateral precursor lesions of testicular carcinoma in situ. In the boy, at the age of 12, numerous germ cells without signs of malignancy were present in bilateral testicular biopsy specimen.

Conclusions

In SF-1 mutations, the neonatal phenotype poorly predicts virilization at puberty. Even in poorly virilized cases at birth, male gender assignment may allow spontaneous puberty without signs of hypogonadotropic hypogonadism, and possibly fertility. Patients with SF-1 mutations are at increased risk for malignant germ cell tumors. In case of preserved gonads, early orchidopexy and germ cell tumor screening is warranted. The finding of premalignant and/or malignant changes should prompt gonadectomy or possibly irradiation.

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Werner F Blum, Cheri Deal, Alan G Zimmermann, Elena P Shavrikova, Christopher J Child, Charmian A Quigley, Stenvert L S Drop, Gordon B Cutler Jr and Ron G Rosenfeld

Objective

We assessed the characteristics of children initially diagnosed with idiopathic isolated GH deficiency (IGHD) who later developed additional (multiple) pituitary hormone deficiencies (MPHD).

Design

Data were analyzed for 5805 pediatric patients with idiopathic IGHD, who were GH-naïve at baseline and GH-treated in the multinational, observational Genetics and Neuroendocrinology of Short Stature International Study.

Methods

Development of MPHD was assessed from investigator diagnoses, adverse events, and concomitant medications. Analyses were performed for all patients and for those who developed MPHD within 4.5 years or had ≥3.5 years, follow-up and continued to have IGHD (4-year cohort).

Results

MPHD developed in 118/5805 (2.0%) children overall, and in 96/1757 (5.5%) in the 4-year cohort. Patients who developed MPHD had more profound GHD, with decreased height SDS, IGF1 SDS and peak stimulated GH, and greater height decrement vs target, compared with children who continued to have IGHD (P<0.001 for each variable). Delivery complications, congenital anomalies, and perinatal/neonatal adverse events occurred more frequently in patients who developed MPHD. The most frequent additional deficiency was TSH (82 patients overall); four patients developed two pituitary hormone deficiencies and one developed three deficiencies. Multivariable logistic regression indicated that years of follow-up (odds ratio 1.55), baseline age (1.17), baseline height SDS (0.69), and peak stimulated GH (0.64) were associated with the development of MPHD.

Conclusions

MPHD is more likely to develop in patients with more severe idiopathic IGHD. Older baseline age, lower baseline height SDS, and longer follow-up duration are associated with increased risk of development of MPHD.

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Christopher J Child, Werner F Blum, Cheri Deal, Alan G Zimmermann, Charmian A Quigley, Stenvert L S Drop, Gordon B Cutler Jr and Ron G Rosenfeld

Objective

To determine characteristics of children initially diagnosed with isolated growth hormone deficiency (IGHD) of organic aetiology, who later developed multiple pituitary hormone deficiencies (MPHD).

Design

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.

Methods

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).

Results

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.

Conclusions

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.