Insights on the phenotypic heterogenity of 11ß-hydroxylase deficiency: clinical and genetic studies in two novel families.

PURPOSE: 11ß-hydroxylase deficiency accounts for 5% of congenital adrenal hyperplasia cases. Diagnosis suspiction is classically based on the association between abnormal virilization, precocious puberty, and hypertension in 46XX or 46XY subjects. We investigated two families with siblings presenting with opposed clinical features, and provided a review of the mechanisms involved in mineralocorticoid-dependent phenotypic heterogeneity. METHODS: The coding region of the CYP11B1 gene of 4 patients was sequenced and familial segregation was confirmed. Clinical characterization and blood steroid profile were performed. RESULTS: Family 1 comprised a female and a male siblings who presented in middle childhood with genital ambiguity (Prader II) and precocious puberty, respectively, associated with hypertension. In the second decade of life, the woman had three full-term pregnancies, and then evolved normotensive with no treatment over a 5-year follow up. On the other hand, her brother had hypertensive end-organ damage at age 24. In family 2, a 2.9 year-old boy presented with precocious puberty and hypertension, whereas his 21 days-old sister had genital ambiguity (Prader III) and salt wasting. A homozygous exon 4 splice site mutation was identified (IVS4ds-1G > A; c.799 G > A) in family 1, while a nonsense mutation in exon 6 (p. Q356X; c.1066 C > T) was found in family 2. CONCLUSION: CYP11B1 mutations were associated with highly variable phenotypes, from mild to severe virilization, and early-onset hypertension or salt wasting. Further analysis of variants in other hypertension-related genes, steroid synthesis and metabolism compensatory pathways, and/or the investigation of chimeric CYP11B genes are needed to clarify the phenotypic heterogeneity in 11ß-hydroxylase deficiency.

Detection and activity of 11 beta hydroxylase (CYP11B1) in the bovine ovary.

Glucocorticoids (GCs) such as cortisol and corticosterone are important steroid hormones with different functions in intermediate metabolism, development, cell differentiation, immune response and reproduction. In response to physiological and immunological stress, adrenocorticotropic hormone (ACTH) acts on the adrenal gland by stimulating the synthesis and secretion of GCs. However, there is increasing evidence that GCs may also be synthesized by extra-adrenal tissues. Here, we examined the gene and protein expression of the enzyme 11ß-hydroxylase P450c11 (CYP11B1), involved in the conversion of 11-deoxycortisol to cortisol, in the different components of the bovine ovary and determined the functionality of CYP11B1 in vitro CYP11B1 mRNA was expressed in granulosa and theca cells in small, medium and large antral ovarian follicles, and CYP11B1 protein was expressed in medium and large antral follicles. After stimulation by ACTH, we observed an increased secretion of cortisol by the wall of large antral follicles. We also observed a concentration-dependent decrease in the concentration of cortisol in response to metyrapone, an inhibitor of CYP11B1. This decrease was significant at 10-5 µM metyrapone. In conclusion, this study demonstrated for the first time the presence of CYP11B1 in the bovine ovary. This confirms that there could be a local synthesis of GCs in the bovine ovary and therefore a potential endocrine responder to stress through these hormones.

Congenital adrenal hyperplasia due to 11-beta-hydroxylase deficiency: description of a new mutation, R384X.

CASE DESCRIPTION: It is presented the phenotype of a new compound heterozygous mutation of the genes R384X and Q356X encoding the enzyme of 11-beta-hydroxylase. CLINICAL FINDINGS: Severe virilization, peripheral hypertension, and early puberty. TREATMENT AND OUTCOME: Managed with hormone replacement therapy (corticosteroid) and antihypertensive therapy (beta-blocker), resulting in the control of physical changes and levels of arterial tension. CLINICAL RELEVANCE: According to the phenotypic characteristics of the patient, it is inferred that the R384X mutation carries an additional burden on the Q356X mutation, with the latter previously described as a cause of 11-beta-hydroxylase deficiency. The description of a new genotype, as in this case, expands the understanding of the hereditary burden and deciphers the various factors that lead to this pathology as well as the other forms of congenital adrenal hyperplasia (CAH), presenting with a broad spectrum of clinical presentations. This study highlights the importance of a complete description of the patient's CAH genetic profile as well as their parents' genetic profile.

DESCRIPCIÓN DEL CASO: Se presenta el fenotipo de una nueva mutación heterocigota compuesta en los genes Q356X y R384X que codifican la enzima 11-beta-hidroxilada. HALLAZGOS CLÍNICOS: Virilización severa, pubertad precoz periférica e hipertensión. TRATAMIENTO Y RESULTADOS: Manejo con terapia de reemplazo hormonal con corticoide y antihipertensivo con beta-bloqueador con lo que se logró controlar los cambios físicos y los niveles de tensión arterial. RELEVANCIA CLÍNICA: Según las características fenotípicas del paciente se infiere que la mutación R384X acarrea una carga adicional a la mutación Q356X, esta última descrita como causa de deficiencia de 11-beta-hidroxilasa. La descripción de nuevos genotipos, como en este caso, permite ampliar la comprensión de la carga hereditaria y descifrar los diversos factores que llevan a que esta patología, así como las demás formas de hiperplasia suprarrenal congénita (HSC), se presenten con un amplio espectro de cuadros clínicos. Esto permite resaltar la importancia de una descripción completa del perfil genético del paciente con HSC y de sus padres.

New genetic abnormalities in non-21α-hydroxylase-deficiency congenital adrenal hyperplasia.

Congenital adrenal hyperplasia comprises a group of autosomal recessive disorders of sexual differentiation and development that occur due to deficiencies in steroidogenic enzymes within the adrenal gland. Using clinical, biochemical, and sequencing data, we describe non-21α-hydroxylase deficiencies in 6 individuals from 4 families originating from endogamic regions in Mexico. Three individuals had 11ß- hydroxylase deficiencies caused by 2 hitherto unreported mutations (P442L substitution and an 11-bp insertion in exon 5 of CYP11B1), while 3 individuals had 17α-hydroxylase/17,20-lyase deficiencies. Sequence-tagged site analysis of 8 individuals from 1 endogamic region suggested that the mutations likely occurred as a result of a founder effect. Although non-21α-hydroxylase enzymatic defects are rare in most populations, characterization of new mutations is important in order to understand the demographic, clinical, biochemical, and molecular variations that exist, and for both active and preventative management in individuals and their communities.

A new presentation of the chimeric CYP11B1/CYP11B2 gene with low prevalence of primary aldosteronism and atypical gene segregation pattern.

Familial hyperaldosteronism type I is caused by an unequal crossover of 11ß-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes, giving rise to a chimeric CYP11B1/CYP11B2 gene (CG). We describe a family carrying a CG with high levels of free 18-hydroxycortisol but low prevalence of primary aldosteronism (PA) and an atypical CG inheritance pattern in a family of 4 generations with 16 adults and 13 children, we measured the arterial blood pressure, serum aldosterone, and plasma renin activity and then calculated the serum aldosterone:plasma renin activity ratio and urinary free 18-hydroxycortisol. We identified the CG by long-extension PCR and predicted its inheritance pattern. The CG was found in 24 of 29 subjects (10 children and 14 adults). In CG+ patients, hypertension and high 18-hydroxycortisol were prevalent (83% and 100%, respectively). High serum aldosterone:plasma renin activity ratio was more frequent in pediatric than adult patients (80% versus 36%; P<0.001). An inverse association between serum aldosterone:plasma renin activity ratio and age was observed (r=-0.48; P=0.018). Sequence analysis identified the CYP11B1/CYP11B2 crossover in a 50-bp region spanning intron 3 of CYP11B1 and exon 4 of CYP11B2. The CG segregation differs from an autosomal disease, showing 100% of CG penetrance in generations II and III. Statistical analysis suggests that inheritance pattern was not attributed to random segregation (P<0.001). In conclusion, we describe a family with an atypical CYP11B1/CYP11B2 gene inheritance pattern and variable phenotypic expression, where the majority of pediatric patients have primary aldosteronism. Most adults have normal aldosterone and renin levels, which could mask them as essential hypertensives.

Bezafibrate, a lipid-lowering pharmaceutical, as a potential endocrine disruptor in male zebrafish (Danio rerio).

Fibrates are pharmaceuticals commonly used to control hypercholesterolemia in humans and they are frequently detected in the freshwater environment. Since cholesterol is the precursor of all steroid hormones, it is suspected that low cholesterol levels will impact steroidogenesis. However, the effect of fibrates on fish reproductive endocrinology is not clear; therefore the aim of the present study was to evaluate the effect of bezafibrate (BZF) on gonadal steroidogenesis and spermatogenesis of zebrafish (Danio rerio). For this purpose, adult males were exposed orally to 1.7, 33 and 70 mg BZF/g food for 21 days. Blood and gonads were collected after 48 h, 7 days and 21 days to evaluate plasma cholesterol and plasma 11-ketotestosterone (11-KT). The expression of gonadal genes involved in the steroidogenesis was quantified to determine a potential mechanism of action, likewise the effect on spermatogenesis was evaluated by examining gonadal histopathology. A time dependent monotonic decrease in the plasma cholesterol concentration was observed in fish exposed to BZF. Plasma 11-KT decreased significantly after 21 days of exposure in fish exposed to the high concentration of BZF. Different gene expression patterns were observed: down-regulation in ppara and pparg mRNA levels was observed in fish exposed to the higher concentrations after 48 h; however, the expression of pparg increased after 21 days. After 21 days an increase in the star and cyp17a1 mRNA expression was observed in fish exposed to 70 mg BZF/g food. Sampling time and bezafibrate concentration explained 52.4% and 20%, respectively, of the gene expression variability. Gonadal histology revealed the presence of germ cell syncytia in the tubular lumen of fish exposed to bezafibrate and also an increased number of cysts containing spermatocytes, which indicate testicular degeneration. The study shows that bezafibrate exerts a hypocholesterolemic effect in adult male zebrafish and its potential as an endocrine disruptor due to its effect on the gonadal steroidogenesis and spermatogenesis.

Frequency of familial hyperaldosteronism type 1 in a hypertensive pediatric population: clinical and biochemical presentation.

Familial hyperaldosteronism type 1 is an autosomal dominant disorder attributed to a chimeric CYP11B1/CYP11B2 gene (CG). Its prevalence and manifestation in the pediatric population has not been established. We aimed to investigate the prevalence of familial hyperaldosteronism type 1 in Chilean hypertensive children and to describe their clinical and biochemical characteristics. We studied 130 untreated hypertensive children (4 to 16 years old). Blood samples for measuring plasma potassium, serum aldosterone, plasma renin activity, aldosterone/renin ratio, and DNA were collected. The detection of CG was performed using long-extension PCR. We found 4 (3.08%) of 130 children with CG who belonged to 4 unrelated families. The 4 patients with CG had very high aldosterone/renin ratio (49 to 242). In addition, we found 4 children and 5 adults who were affected among 21 first-degree relatives. Of the 8 affected children, 6 presented severe hypertension, 1 presented prehypertension, and 1 presented normotension. High serum aldosterone levels (>17.7 ng/dL) were detected in 6 of 8 subjects (range: 18.6 to 48.4 ng/dL) and suppressed plasma renin activity (≤0.5 ng/mL per hour) and high aldosterone/renin ratio (>10) in 8 of 8 children (range: 49 to 242). Hypokalemia was observed in only 1 of 8 children. We demonstrated that the prevalence of familial hyperaldosteronism type 1 in a pediatric hypertensive pediatric population was surprisingly high. We found a high variability in the clinical and biochemical characteristics of the affected patients, which suggests that familial hyperaldosteronism type 1 is a heterogeneous disease with a wide spectrum of presentations even within the same family group.

A de novo unequal cross-over mutation between CYP11B1 and CYP11B2 genes causes familial hyperaldosteronism type I.

UNLABELLED: Familial hyperaldosteronism type I (FH-I) is an autosomal dominant disorder caused by an unequal cross-over of the gene encoding steroid 11ß-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2), giving rise to a chimeric CYP11B1/CYP11B2 gene that displays aldosterone synthase activity regulated by ACTH instead of angiotensin II. AIM: To report an unprecedented case of a de novo unequal crossover mutation between CYP11B1 and CYP11B2 genes causing FH-I. PATIENTS AND METHODS: The index case is a 45-yr-old Chilean male diagnosed with primary aldosteronism (PA). All family members were also studied: his biological parents, 1 brother, 6 sisters, 2 daughters, and 1 son. Plasma renin activity, serum aldosterone, and its ratio were measured in all patients. Genetic analyses were performed using long-extension PCR (XL-PCR), DNA sequencing and Southern blot methods. RESULTS: PA was diagnosed for the index case, 1 of his daughters, his son but not for his parents or siblings. XLPCR and Southern blotting demonstrated the presence of the chimeric CYP11B1/CYP11B2 gene solely in PA-affected subjects, suggesting a case of a de novo mutation. Sequence analysis showed the unequal cross-over CYP11B1/CYP11B2 at intron 2 (c.2600-273 CYP11B2). We also identified a polymorphism at the same intron (c.2600-145C>A CYP11B2) in the genome of the index case's father. CONCLUSION: We describe an unprecedented case of unequal cross-over mutation for the chimeric CYP11B1/CYP11B2 gene causing FH-I, which may be linked to a polymorphism in the index case's father germ line.

Aldosterone, plasma Renin activity, and aldosterone/renin ratio in a normotensive healthy pediatric population.

Primary aldosteronism is an important cause of secondary hypertension and is suspected in adults with an aldosterone/renin ratio > or =25. The normal aldosterone/renin ratio is unknown in children. The aim was to establish serum aldosterone, plasma renin activity, and aldosterone/renin ratio values in a healthy pediatric population. A cross-sectional study was performed in 211 healthy normotensive children (4 to 16 years old). Two subgroups of normotensive children were obtained: with hypertensive parents (NH) (n=113) and normotensive parents (n=98). Blood samples for measuring serum aldosterone, plasma renin activity, aldosterone/renin ratio, and DNA were collected. In subjects with aldosterone/renin ratio > or =25, the chimeric CYP11B1/CYP11B2 gene was investigated by long-extension PCR. Results are expressed as median [Q(1)-Q(3)]. NH and normotensive parents groups were similar in serum aldosterone (6.5 [3.6 to 9.0] ng/dL versus 6.5 [2.9 to 9.7] ng/dL; P=0.968) and plasma renin activity (2.3 [1.6 to 3.1] versus 2.4 [1.7 to 3.7] ng/mL per hour; P=0.129). The aldosterone/renin ratio was higher in the NH group, but this difference did not reach statistical significance (2.8 [1.9 to 4.1] versus 2.5 [1.4 to 4.0], P=0.104). In one subject of the NH group, the chimeric CYP11B1/CYP11B2 gene was detected. We demonstrated that normal aldosterone/renin ratio values in a healthy pediatric population without NH were lower than those reported for an adult normotensive population.

Molecular characterization of cyp11a1 and cyp11b1 and their gene expression profile in pejerrey (Odontesthes bonariensis) during early gonadal development.

Sex steroids are known to be involved in gonadal differentiation in fish, but whether androgens are early mediators of testis differentiation remains unclear. We studied the sex-related developmental variations in the gene expression of two key enzymes involved in steroids and androgen synthesis (cyp11a1 and cyp11b1) in trunks and isolated gonads of pejerrey (Odontesthes bonariensis) larvae during and after the sex determination period. Also, and in order to have a better characterization of this process we studied the expression of Sertoli (dmrt1, amh, sox9) and Leydig (nr5a1 or sf-1) cell markers as well as a gene with higher expression in females (cyp19a1a). No clear differences were observed in the expression of cyp11a1 and cyp11b1 during the temperature-sensitive window in the trunk of pejerrey larvae. Nevertheless, a clear increase of cyp11b1 was observed in isolated gonads taken from fish reared at the male producing temperature. In these gonads we also confirmed the trends of genes with higher expression in males (dmrt1, amh) and females (cyp19a1a) as previously described in larval trunks of pejerrey. Our results showed that the expression of cyp11b1 was positively associated with the morphological differentiation of the testis. Nevertheless the involvement of 11-oxygenated androgens during the temperature-sensitive window could not be clearly established.

Novel mutations in CYP11B1 gene leading to 11 beta-hydroxylase deficiency in Brazilian patients.

BACKGROUND: Deficiency of 11 beta-hydroxylase results in the impairment of the last step of cortisol synthesis. In females, the phenotype of this disorder includes different degrees of genital ambiguity and arterial hypertension. Mutations in the CYP11B1 gene are responsible for this disease. OBJECTIVE: The objective of the study was to screen the CYP11B1 gene for mutations in two unrelated Brazilian females with congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. DESIGN: The coding and intron-exon junction regions of CYP11B1 were totally sequenced. A putative splice mutation was further investigated by minigene transcription. RESULTS: We report two novel CYP11B1 mutations in these Brazilian patients. An Arabian Lebanese descendent female was found to be homozygous for a cytosine insertion at the beginning of exon 8, changing the 404 arginine to proline. It alters the open reading frame, creating a putative truncated protein at 421 residue, which eliminates the domain necessary for the association of heme prosthetic group. A severely virilized female was homozygous for the g.2791G>A transition in the last position of exon 4. This nucleotide is also part of 5' intron 4 donor splice site consensus sequence. Minigene experiments demonstrated that g.2791G>A activated an alternative splice site within exon 4, leading to a 45-bp deletion in the transcript. The putative translation of such modified mRNA indicates a truncated protein at residue 280. CONCLUSIONS: We describe two novel mutations, g.4671_4672insC and g.2791G>A, that drastically affects normal protein structure. These mutations abolish normal enzyme activity, leading to a severe phenotype of congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency.

[Subclinical endothelial inflammation markers in a family with type I familial hyperaldosteronism caused by a de novo mutation]. / Marcadores de inflamación endotelial subclínica en una familia con hiperaldosteronismo familiar tipo I por mutación de novo.

BACKGROUND: Type I familial hyperaldosteronism is caused by the presence of a chimaeric gene CYPl 1B1/CYP11BZ which encodes an enzyme with aldosterone synthetase activity regulated by adrenocorticotrophic hormone (ACTH). Therefore, in patients with FH I is possible to normalize the aldosterone levels with glucocorticoid treatment. Recently it has been shown that aldosterone plays a role in the production of endothelial oxidative stress and subclinical inflammation. AIM: To evaluate subclinical endothelial inflammation markers, like Metalloproteinase 9 (MMP-9) and ultrasensitive C reactive protein (usPCR), before and after glucocorticoid treatment in family members with FH-I caused by a de novo mutation. PATIENTS AND METHODS: We report three subjects with FH-I in a single family (proband, father and sister). We confirmed the presence of a chimaeric CYPl 1B1/CYP11B2 gene by long-PCR in all of them. Paternal grandparents were unaffected by the mutation. The proband was a 13-year-old boy with hypertension stage 2 (in agree to The Joint National Committee VII, JNC-VII), with an aldosterone/plasma rennin activity ratio equal to 161. A DNA paternity test confirmed the parental relationship between the grandparents and father with the index case. MMP-9 and usPCR levels were determined by gelatin zymography and nephelometry, respectively. RESULTS: All affected subjects had approximately a 50% increase in MMP-9 levels. Only the father had an elevated usPCR. The endothelial inflammation markers returned to normal range after glucocorticoid treatment. CONCLUSIONS: We report a family carrying a FH-I caused by a de novo mutation. The elevation of endothelial inflammation markers in these patients and its normalization after glucocorticoid treatment provides new insight about the possible deleterious effect of aldosterone on the endothelium.

21-hydroxylase deficiency transiently mimicking combined 21- and 11beta-hydroxylase deficiency.

21-Hydroxylase deficiency (21OHD) is the commonest form of congenital adrenal hyperplasia, while 11betaOHD represents 5% of cases. Although both result from mutations in distinct genes, cases of 'apparent' combined 21OHD and 11betaOHD (AC21,11OHD) have been occasionally reported. A 6 year-old girl, born with ambiguous genitalia and salt-loss, had serum elevations (ng/dl) of androstenedione (>1,000), 17-hydroxyprogesterone (17OHP; 38,483), 21-deoxycortisol (21DF; 23,338), and 11-deoxycortisol (S; 4,928), suggesting AC21,11OHD. CYP21A and CYP11B1 genotyping identified mutations only in the former. On follow-up, serum S became normal but 17OHP and 21DF were still elevated. ACTH stimulation disclosed elevated levels of 17OHP and 21DF, but unresponsive S and undetectable deoxycorticosterone. The hormonal pattern initially suggested AC21,11OHD, but subsequent normalization of S showed transient 11-hydroxylase inhibition. This may have occurred by enzyme or co-enzyme immaturity or functional discrepancy, but also by selective inhibition of 11betaOH by excess intra-adrenal concentration of androgens, acting as pseudo-substrates for this enzyme.

[11beta-hydroxylase deficiency]. / Deficiência da 11beta-hidroxilase.

Congenital adrenal hyperplasia due to 11beta-hydroxylase enzyme deficiency is a result of the impairment of 11-deoxycortisol to cortisol conversion. In general, it is responsible for less than 5% of the congenital adrenal hyperplasia cases. The clinical expression of androgen excess in females includes several degrees of genital ambiguity, varying from clitoromegaly to complete virilization. Due to the accumulation of mineralocorticoids, approximately 50% of the patients develop blood hypertension. Mutations in the CYP11B1 gene are responsible for the disease. Biochemical and molecular characteristics of the enzyme and their implications in the clinical presentation of 11beta-hydroxylase deficiency are reviewed here.

Genetic study of patients with dexamethasone-suppressible aldosteronism without the chimeric CYP11B1/CYP11B2 gene.

Glucocorticoid-remediable aldosteronism is an inherited disorder caused by a chimeric gene duplication between the CYP11B1 (11beta-hydroxylase) and CYP11B2 (aldosterone synthase) genes. The disorder is characterized by hyperaldosteronism and high levels of 18-hydroxycortisol and 18-oxocortisol, which are under ACTH control. The diagnosis of glucocorticoid-remediable aldosteronism had been traditionally made using the dexamethasone suppression test; however, recent studies have shown that several patients with primary aldosteronism and a positive dexamethasone suppression test do not have the chimeric CYP11B1/CYP11B2 gene. The aim of this work was to evaluate whether other genetic alterations exist in CYP11B genes (gene conversion in the coding region of CYP11B1 or in the promoter of CYP11B2) that could explain a positive dexamethasone suppression test and to determine another genetic cause of glucocorticoid-remediable aldosteronism. We also evaluated the role of 18-hydroxycortisol as a specific biochemical marker of glucocorticoid-remediable aldosteronism. We studied eight patients with idiopathic hyperaldosteronism, a positive dexamethasone suppression test, and a negative genetic test for the chimeric gene. In all patients we amplified the CYP11B1 gene by PCR and sequenced exons 3-9 of CYP11B1 and a specific region (-138 to -284) of CYP11B2 promoter. We also measured the levels of 18-hydroxycortisol, and we compared the results with those found in four subjects with the chimeric gene. None of eight cases showed abnormalities in exons 3-9 of CYP11B1, disproving a gene conversion phenomenon. In all patients a fragment of 393 bp corresponding to a specific region of the promoter of CYP11B2 gene was amplified. The sequence of the fragment did not differ from that of the wild-type promoter of the CYP11B2 gene. The 18-hydroxycortisol levels in the eight idiopathic hyperaldosteronism patients and four controls with chimeric gene were 3.9 +/- 2.3 and 21.9 +/- 3.5 nmol/liter, respectively (P < 0.01). In summary, we did not find other genetic alterations or high levels of 18-hydroxycortisol that could explain a positive dexamethasone suppression test in idiopathic hyperaldosteronism. We suggest that the dexamethasone suppression test could lead to an incorrect diagnosis of glucocorticoid-remediable aldosteronism.

Serum 18-hydroxycortisol in primary aldosteronism, hypertension, and normotensives.

This study reports the determination of plasma 18-hydroxycortisol (18-OHF) using a new and easy enzyme-linked immunosorbent assay (ELISA) method in primary aldosteronism and compares the values found in essential hypertensives and normotensive controls. In primary aldosteronism, we evaluated usefulness of plasma 18-OHF determination and the dexamethasone suppression test in the diagnosis of glucocorticoid-remediable aldosteronism using the genetic test as the gold standard. We studied 31 primary aldosteronism patients, 101 essential hypertensives, and 102 healthy normotensive controls. The plasma 18-OHF was measured using a biotin-avidin enzyme-linked assay by a new and purified polyclonal antibody. The 18-OHF value in primary aldosteronism was 6.3+/-8.05 nmol/L; this value is significantly higher than the value found in essential hypertensives and normotensive controls (2.81+/-1.42 and 2.70+/-1.41 nmol/L, respectively; P<0.0005). In primary aldosteronism, 4 of 31 patients had 18-OHF levels that were 10 times higher than the normal upper limit (2.983 nmol/L). The dexamethasone suppression test in primary aldosteronism patients was positive (serum aldosterone <4 ng/dL) in 13 of 31 cases. A chimeric CYP11B1/CYP11B2 gene was demonstrated in 4 primary aldosteronism patients, corresponding to the same cases that had higher level of 18-OHF. In conclusion, plasma 18-OHF determination by this ELISA method is reliable for detecting glucocorticoid-remediable aldosteronism, and it does so better than the dexamethasone suppression test.

[Polycystic ovary syndrome of extra-ovarian origin. Review]. / Síndrome de ovarios poliquísticos de origen extraovárico. Revisión.

An established fact in the polycystic ovarian syndrome (POS) is an abnormal ovarian steroidogenesis. Though this suggest an intrinsic ovarian defect, the syndrome could also be influenced by factors outside the ovaries. Although of unknown etiology, the POS is one of the most frequent endocrine disorders in the gynecologic practice. The disorder is characterized by ultrasound findings of enlarged polycystic ovaries, hyperandrogenism, menstrual disorders, obesity and including the appearance of infertility. There are a series of mechanisms involved in the extraovarian androgen increase in patients with POS. Among these mechanisms are implicated those of central and peripheral origin, genetic factors and adrenocortical dysfunction. In the same way, the alterations produced could imply genetic, molecular biological, biochemical, physiological and endocrinological factors. Sometimes all these factors could interact at the same time. The high serum androgen level could stop the pituitary gonadotropin production, either as a direct mechanism or as a result of its peripheral conversion. The increased androgens also explain the manifestations of clinical acne, hirsutism, and the detention in follicular ovarian maturation. All these manifestations are related with the menstrual disorders, anovulation, and infertility that these patients develop. The characteristics of the extraovarian POS include the 17-hydroxyprogesterone elevation in response to the ACTH test and the dexamethasone suppression of adrenal androgens. It is possible to improve the ovarian function in some patients with POS. This could be achieved with clomiphene citrate associated with glucocorticoids to induce ovulation.

Familial hyperaldosteronism.

Aldosterone, the major circulating mineralocorticoid, participates in blood volume and serum potassium homeostasis. Primary aldosteronism is a disorder characterised by hypertension and hypokalaemia due to autonomous aldosterone secretion from the adrenocortical zona glomerulosa. Improved screening techniques, particularly application of the plasma aldosterone:plasma renin activity ratio, have led to a suggestion that primary aldosteronism may be more common than previously appreciated among adults with hypertension. Glucocorticoid-remediable aldosteronism (GRA) was the first described familial form of hyperaldosteronism. The disorder is characterised by aldosterone secretory function regulated chronically by ACTH. Hence, aldosterone hypersecretion can be suppressed, on a sustained basis, by exogenous glucocorticoids such as dexamethasone in physiologic range doses. This autosomal dominant disorder has been shown to be caused by a hybrid gene mutation formed by a crossover of genetic material between the ACTH-responsive regulatory portion of the 11ss-hydroxylase (CYP11B1) gene and the coding region of the aldosterone synthase (CYP11B2) gene. Familial hyperaldosteronism type II (FH-II), so named to distinguish the disorder from GRA or familial hyperaldosteronism type I (FH-I), is characterised by autosomal dominant inheritance of autonomous aldosterone hypersecretion which is not suppressible by dexamethasone. Linkage analysis in a single large kindred, and direct mutation screening, has shown that this disorder is unrelated to mutations in the genes for aldosterone synthase or the angiotensin II receptor. The precise genetic cause of FH-II remains to be elucidated.