Tpit is a highly cell-restricted transcription factor that is required for expression of the pro-opiomelanocortin (POMC) gene and for terminal differentiation of the pituitary corticotroph lineage. ...Its exclusive expression in pituitary POMC-expressing cells has suggested that its mutation may cause isolated deficiency of pituitary adrenocorticotropin (ACTH). We now show that Tpit-deficient mice constitute a model of isolated ACTH deficiency (IAD) that is very similar to human IAD patients carrying TPIT gene mutations. Through genetic analysis of a panel of IAD patients, we show that TPIT gene mutations are associated at high frequency with early onset IAD, but not with juvenile forms of this deficiency. We identified seven different TPIT mutations, including nonsense, missense, point deletion, and a genomic deletion. This work defines congenital early onset IAD as a relatively homogeneous clinical entity caused by recessive transmission of loss-of-function mutations in the TPIT gene.
Heterozygosity in 21-hydroxylase deficiency (21OHD) has been associated with hyperandrogenemic symptoms in children and adults. Moreover, the carrier status is mandatory for genetic counseling. We ...aimed at defining a hormonal parameter for carrier detection by mass spectrometry.
Eleven basal and ACTH-stimulated steroid hormones of heterozygous carriers of CYP21A2 mutations and control individuals were compared.
Hormones were determined in plasma samples by liquid chromatography tandem mass spectrometry (LC-MS/MS) in 58 carriers (35 males, 23 females, age range 6-78 years) and 44 random controls (25 males, 19 females, age range 8-58 years).
Heterozygotes could be identified best applying the 17-hydroxyprogesterone+21-deoxycortisol/cortisol×1000 ((17OHP+21S)/F×1000) equation 30 min after ACTH injection. An optimal cut-off value of 8.4 provided 89% sensitivity and specificity. Considering this data and a published frequency of heterozygotes of 1/50 to 1/61, the positive predictive value (PPV) of this cut-off is 12%. Of note, the negative predictive value (NPV) excluding heterozygosity in a given patient is 99.8%.
Considering only marginal biochemical effects anticipated from heterozygosity, the stimulated ((17OHP+21S)/F×1000) identifies and excludes heterozygotes remarkably well. Nevertheless, LC-MS/MS cannot replace genetic testing, since sensitivity and specificity did not reach 100%. However, due to the considerably high NPV of the optimal cut-off and to a specificity of even 100% applying a cut-off higher than 14.7, hormonal assessment of heterozygosity can be of significant aid in conditions with limited access to genetic testing, as in some health care systems. The ((17OHP+21S)/F×1000) equation can guide diagnostic considerations in the differential diagnosis of hyperandrogenism.
A considerable number of patients with central precocious puberty (CPP) treated with depot GnRH agonists have reached final height (FH). The aim of this prospective, multicentric study was the ...evaluation of the benefits, side-effects, and long term outcome of depot GnRH agonist therapy. We investigated 50 young women (mean +/- SD age, 16.7+/-2.6 yr; range, 12.9-23.4 yr) at FH. They received depot triptorelin over a period of 4.4+/-2.1 yr (range, 1.0-9.7 yr). Target height (TH) and predicted adult height (PAH) at the start of treatment were 163.6+/-6.2 and 154.9+/-9.6 cm, respectively (P < 0.05). FH was 160.6+/-8.0 cm (FH vs. TH, P = NS; FH vs. PAH, P < 0.05). Young patients showed the highest height gain (FH minus initial PAH). Seventy-eight percent of all patients reached a FH within their TH range. Even in young patients and those with an unfavorable initial PAH below the TH range, 60% reached a FH within their individual TH range. Standardized bone mineral density and standardized bone mineral density SD score investigated by dual energy x-ray absorptiometry of the lumbar spine (L1-L4) were 1040.9+/-124.2 mg/cm2 and 0.0+/-1.0; those of the femoral neck were 902.2+/-115.4 mg/cm2 and 0.2+/-1.0, respectively. The SD score of the ratio of sitting height over lower leg length was normal (0.3+/-1.2). Body mass index SD scores at pretreatment, at the end of treatment, and at FH were not significantly different (2.0+/-2.0, 2.0+/-2.0, and 1.7+/-2.2, respectively). Menarche or remenarche started at age 12.3+/-1.4 yr (range, 9.3-15.8 yr) in all patients. In conclusion, long term depot GnRH agonist treatment of CPP girls preserved genetic height potential and improved FH significantly combined with normal body proportions. No negative effect on bone mineral density and reproductive function was seen. Treatment neither caused nor aggravated obesity.
Precocious puberty is generally defined as the appearance of secondary sex characteristics before age 8 years in girls (or menarche before age 9 years) and before 9 years in boys. The overall ...incidence of sexual precocity is estimated to be 1:5000 to 1:10 000 children. The female-to-male ratio is ∼10:1. In addition to the psychosocial disturbances associated with precocious puberty, the premature pubertal growth spurt (with less time for prepubertal growth) and the accelerated bone maturation result in reduced adult height. Precocious puberty may be gonadotrophin-dependent i.e. of central origin with premature activation of the gonadotrophin-releasing hormone (GnRH) pulse generator or gonadotrophin-independent (i.e. peripheral where the GnRH pulse generator is suppressed). This can be determined by GnRH testing. The pathophysiology is the basis for different diagnostic and therapeutic strategies, i.e. in the first case a stimulated LH/FSH ratio >1 and suppressive treatment with GnRH agonists (e.g. in hypothalamic hamartoma), and in the second decreased gonadotrophins and removal or suppression of the endogenous or exogenous sex steroid source (e.g. congenital adrenal hyperplasia). While several cases of gonadotrophin-independent precocious puberty due to oestrogen exposure via the transdermal, oral, or inhalative route have been reported, no case is known with the development of subsequent secondary central precocious puberty. Food contamination with oestrogens is theoretically possible, but would most probably be sporadic and, thus, would not lead to precocious puberty. As steroid hormones in meat production are banned in the European Union, no data on the impact of environmental oestrogenic substances on human maturation are currently available. In conclusion, the risk for children to develop precocious puberty through exposure to oestrogens (or androgens) in the environment or in food is very low. Nevertheless, studies of the effects of defined environmental oestrogenic substances on the human reproductive system and on pubertal development are warranted.
Congenital adrenal hyperplasia (CAH) is caused by a defect in the biosynthesis of cortisol that results in maximal activity of the hypothalamic-pituitary adrenal axis with hyperplasia of the adrenals ...and hyperandrogenism due to the accumulation of androgen precursors. In the salt-wasting subtype of the disorder, which accounts for appr. 75 % of patients with classical CAH, patients are unable to synthesise sufficient amounts of aldosterone and are prone to life-threatening salt-losing crises, whereas the simple virilising form is predominantly characterized by clitoris hypertrophy and posterior labial fusion. In addition, a non-classical variant can be discerned which in most cases is diagnosed at the time of puberty or early adolescence when hirsutism and menstrual irregularities may occur. The vast majority of CAH patients have 21-hydroxylase deficiency (90 - 95 %). Less common forms, such as 11beta-hydroxylase deficiency, will not be discussed in this review. Unfortunately, a considerable number of CAH patients is lost to regular and competent follow-up once they move out of paediatric care. This is most probably the result of insufficient co-operation between paediatric and adult endocrinologists at the time of transition from adolescence to adulthood. Furthermore, there is a lack of clinical guidance regarding psychosexual development in these patients. In this overview we will focus on special aspects of CAH treatment in adolescence and adulthood, and report on our 10-year experience with a transfer system for endocrine patients from paediatric to internal medical care, known as the "Kieler Modell". For practical purposes, we here provide charts for follow-up of CAH patients that can be adapted for use in any endocrine outpatient clinic.
Summary
objective In girls with congenital adrenal hyperplasia (CAH), genital ambiguity usually leads to a rapid neonatal diagnosis. Rarely, CAH causes complete virilization and male sex assignment ...with a delayed diagnosis. After being confronted with very specific problems in two of such patients, we collected data of patients with CAH and complete virilization in a nationwide study to delineate specific problems of these rare patients in order to improve their management.
design and patients Through the German Working Group of Paediatric Endocrinology (Arbeitsgemeinschaft Pädiatrische Endokrinologie, APE), questionnaires were sent to all members caring for patients with CAH and complete virilization in their endocrine clinics. Data from 16 patients from 10 paediatric endocrine centres were assessed by questionnaire.
results The following problems have been encountered. (1) Sex assignment/gender identity: initially all patients had a male sex assignment. Six patients were diagnosed during the first month of life. Five were reassigned to female sex immediately, one at the age of 19 months. Except in one girl demonstrating some tomboyish behaviour, gender role behaviour in these patients did not differ from unaffected girls. Ten patients were diagnosed late at 3·4–7 years of age. In seven patients with a late diagnosis, male sex assignment was maintained; one of them expressed some concerns about living as a male. In three patients late sex reversal was performed, gender identity is very poor in one and new sex assignment is currently under consideration. (2) Surgery: irrespective of the sex assigned, all patients had between one and three surgical procedures, including clitoris reduction and (repeated) vaginoplasties in patients with female sex assignment. Hysterectomy and ovarectomy were performed in patients with male sex assignment. (3) Short stature: patients with a late diagnosis of CAH had extremely advanced bone ages of +6·3 to +9·5 years, leading to severely reduced final height of 137 to 150 cm in adult patients. Patients tended to follow height percentiles of genetic females. One pubertal patient was suicidal due to short stature. (4) Central precocious puberty (CPP): prolonged exposition to adrenal androgens led to CPP in one patient. He was treated with GnRH analogues until gonadectomy.
conclusions Patients with CAH and complete virilization have a high risk of being diagnosed late. There are major problems and uncertainties of the patients’ families and the treating physicians concerning gender assignment. Gender identity is disturbed in some patients. In addition, multiple surgical procedures are necessary and short stature as well as central precocious puberty might be important to avoid late sequelae. While some surgical interventions are probably unavoidable, most of these issues could be resolved with an early diagnosis. Thus, especially for these patients, a neonatal screening programme for CAH would be of paramount importance.
X-linked congenital adrenal hypoplasia (AHC) is a rare developmental disorder of the human adrenal cortex and is caused by deletion or mutation of the DAX-1 gene, a recently discovered member of the ...nuclear hormone receptor superfamily. Hypogonadotropic hypogonadism is frequently associated with AHC. AHC occurs as part of a contiguous gene syndrome together with glycerol kinase deficiency (GKD) and Duchenne's muscular dystrophy. The present series, collected over the past 2 decades, includes 18 AHC boys from 16 families: 4 with AHC, GKD, and Duchenne's muscular dystrophy; 2 with AHC and GKD; and 12 with AHC (5 young adults with hypogonadotropic hypogonadism). Most of the boys presented with salt wasting and hyperpigmentation during the neonatal period. Plasma steroid determinations performed in the first weeks of life often showed confusing results, probably caused by steroids produced in the neonates' persisting fetocortex. Aldosterone deficiency usually preceded cortisol deficiency, which explains why the patients more often presented with salt-wasting rather than with hypoglycemic symptoms. An ACTH test was often necessary to detect cortisol deficiency in the very young infants. In some patients, serial testing was necessary to establish the correct diagnosis. In 4 boys studied during the first 3 months after birth, we found pubertal LH, FSH, and testosterone plasma levels indicating postnatal transient activation of the hypothalamic-pituitary-gonadal axis as in normal boys. Previous studies have shown that the DAX-1 gene is deleted in the AHC patients with a contiguous gene syndrome and is mutated in nondeletion patients. Most of the point mutations identified in AHC patients were frameshift mutations and stop mutations. In the 15 patients available for molecular analysis of the DAX-1 gene, there were large deletions in 6 patients and point mutations in another 7 patients. All of the point mutations identified in the present study resulted in a nonfunctional truncated DAX-1 protein. Two brothers with primary adrenal insufficiency and a medical history that strongly suggested AHC had no mutation in the DAX-1 gene. Thus, additional, as yet unknown genes must play a part in normal adrenal cortical development.
Mutations of the PROP-1 gene cause combined pituitary hormone deficiency. Progressive ACTH/cortisol insufficiency is found in a few patients. Congenital hypoplasia of the anterior pituitary gland is ...the most common magnetic resonance imaging finding in patients with PROP-1 mutations. We present two brothers with compound heterozygosity for the two mutations 150delA and 301-302delAG of the PROP-1 gene. Both showed combined pituitary hormone deficiency of GH, TSH, PRL, and gonadotropins, as is typical for PROP-1 deficiency. We observed a developing insufficiency of ACTH and cortisol secretory capacity in both patients. Computed tomography revealed an enlarged pituitary in the older brother at 3.5 yr of age. Repeated magnetic resonance imaging after 12 yr showed a constant hypoplasia of the anterior pituitary lobe. Similarly, magnetic resonance imaging of the younger brother showed a constant enlargement of the anterior pituitary gland until 10 yr. At the age of 11 yr, the anterior pituitary was hypoplastic. The reason for pituitary enlargement in early childhood with subsequent decrease in pituitary size is not known. We speculate that altered expression of early transcription factors could be involved. Because both patients have the same PROP-1 mutations and an identical pattern of combined pituitary hormone deficiency, we suggest that early pituitary enlargement may be the typical course in such patients in whom pituitary surgery is not indicated.
Congenital adrenal hyperplasia (CAH) OMIM 201 910 is a group of autosomal recessive disorders most commonly due to 21-hydroxylase deficiency and presenting with a wide range of clinical ...manifestations. A limited number of inactivating pseudogene-derived mutations account for the majority of 21-hydroxylase gene ( CYP21) mutations, additional rare mutations can be found in single families and small populations. We found three novel CYP21 mutations in CAH patients suffering from the classical form of the disease, of which one is a frameshift mutation (1353-1354insA) leading to a premature termination codon (K277K, Q228A...E294X), one results in a premature stop codon (2551C>T, R444X), and one is a missense mutation (2609T>C; P463L). The frameshift and premature stop mutations can be predicted to result in a CYP21 protein without any residual enzyme activity. To determine the functional consequences of the P463L mutation, the IN VITRO enzyme activity was studied in COS-7 cells and revealed a reduced 21-hydroxylase activity of 2.6+/-0.8 (SD)% for the conversion of 17-hydroxyprogesterone (17OHP) to 11-deoxycortisol and of 3.0+/-0.5 % for the conversion of progesterone to 11-deoxycorticosterone (DOC). We conclude that functional analyses of unknown mutations provide information on the disease severity and should be always performed when novel CYP21 mutations are detected. Knowledge of the residual 21-hydroxylase function improves both genetic counselling and individual clinical management in CAH patients.
We recently found that postzygotic de novo mutations occur at the expected high rate of an X-linked recessive mutation in androgen insensitivity syndrome. The resulting somatic mosaicism can be an ...important molecular determinant of in vivo androgen action caused by expression of the wild-type androgen receptor (AR). However, the clinical relevance of this previously underestimated genetic condition in androgen insensitivity syndrome has not been investigated in detail as yet. Here, we present the clinical and molecular spectrum of somatic mosaicism considering all five patients with mosaic androgen insensitivity syndrome, whom we have identified since 1993: Patient 1 (predominantly female, clitoromegaly), 172 TTA(Leu)/TGA(Stop); patient 2 (ambiguous), 596 GCC(Ala)/ACC(Thr); patient 3 (ambiguous), 733 CAG(Gln)/ CAT(His); patient 4 (completely female), 774 CGC(Arg)/TGC (Cys); and patient 5 (ambiguous), 866 GTG(Val)/ATG(Met). Serum sex hormone binding globulin response to stanozolol, usually correlating well with in vivo AR function, was inconclusive for assessment of the phenotypes in all tested mosaic individuals. An unexpectedly strong virilization occurred in patients 1, 3, and 5 compared with phenotypes as published with corresponding inherited mutations and compared with the markedly impaired transactivation caused by the mutant ARs in cotransfection experiments. Only the prepubertal virilization of patients 2 and 4 matched appropriately with transactivation studies (patient 4) or the literature (patients 2 and 4). However, partial pubertal virilization in patient 4 caused by increasing serum androgens and subsequent activation of the wild-type AR could not be excluded. We conclude that somatic mosaicism is of particular clinical relevance in androgen insensitivity syndrome. The possibility of functionally relevant expression of the wild-type AR needs to be considered in all mosaic individuals, and treatment should be adjusted accordingly.
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