Combined 21- and 11 beta-hydroxylase deficiency in familial congenital adrenal hyperplasia

Differential activity of the corticosteroidogenic enzymes in normal cycling women and women with polycystic ovary syndrome

The phenotypic complex of patients with definitive diagnosis of polycystic ovary syndrome may include patients with normal and high serum androgen levels. Patients with hyperandrogenemia seem to present higher risk of changes to the glucose and lipid metabolism and, eventually, of earlier development of cardiovascular diseases than normoandrogenemic patients or healthy women. From a laboratory and clinical point of view, it is important to check androgen levels in patients with polycystic ovary syndrome. The identification of partial insufficiency of a given corticosteroidogenic enzyme is also relevant to understand the physiopathology of androgen increase in polycystic ovary syndrome. Therefore, the present review analyzes the functions of the different enzymes involved in the ovary and adrenal steroidogenesis in normal cycling women and in patients with polycystic ovary syndrome. In addition, it emphasizes appropriate reason for investigating eventual enzyme deficiency to provide rationale for prescription and follow-up of women with polycystic ovary syndrome.

Mild Adrenal Steroidogenic Defects and ACTH-Dependent Aldosterone Secretion in High Blood Pressure: Preliminary Evidence

Introduction. Adrenal glands play a major role in the control of blood pressure and mild defects of steroidogenesis and/or inappropriate control of mineralocorticoid production have been reported in high blood pressure (HBP). Patients and Methods. We used a specific protocol for the evaluation of 100 consecutive patients with inappropriate or recent onset HBP. Specific methods were used to confirm HBP and to diagnose secondary forms of HBP. In addition we tested adrenal steroidogenesis with the common cosyntropin test, modified to include the simultaneous measurement of renin and aldosterone besides 17-hydroxyprogesterone (17OHP) and 11-deoxycortisol (S). Results. Secondary forms of HBP were diagnosed in 32 patients, including 14 patients with primary hyperaldosteronism (PA) (14%) and 10 patients with pheochromocytoma (10%). Mild defects of the 21-hydroxylase (21OHD) and 11-hydroxylase (11OHD) enzymes were common (42%). ACTH-dependent aldosterone secretion was found in most patients (54%) and characteristically in those with mild defects of adrenal steroidogenesis (>60%), PA (>75%), and otherwise in patients with apparent essential HBP (EHBP) (32%). Discussion. Mild defects of adrenal steroidogenesis are common in patients with HBP, occurring in almost half of the patients. In those patients as well as in patients with apparent EHBP, aldosterone secretion is commonly dependent on ACTH.

Adrenal hypoplasia congenita presenting as congenital adrenal hyperplasia

We report on a patient with genetically confirmed adrenal hypoplasia congenita (AHC) whose presentation and laboratory abnormalities were consistent with the more common condition, congenital adrenal hyperplasia (CAH). The patient presented with failure to thrive and salt wasting. General appearance showed marked hyperpigmentation and normal male genitalia. He displayed mildly elevated 17-hydroxyprogesterone and markedly elevated 11-deoxycortisol levels at baseline and with ACTH stimulation testing. Results were consistent with 11 β -hydroxylase deficiency. He required glucocorticoids and high doses of mineralocorticoids. The marked elevation in 11-deoxycortisol directed our clinical reasoning away from a hypoplastic condition and towards a hyperplasic adrenal condition. Sequencing of the DAX1 gene (named for dosage-sensitive sex reversal (DSS) locus and the AHC locus on the X chromosome) revealed a missense mutation. A review of the literature revealed that elevated 11-deoxycortisol levels have been noted in kindreds with DAX1 mutations, but only when measured very early in life. A mouse model has recently been described that displays elevated 11-deoxycorticosterone levels and evidence for hyperplasia of the zona glomerulosa of the adrenal gland. We conclude that DAX1 testing may be considered in patients with laboratory evidence of 11 β -hydroxylase deficiency, especially in those with severe salt wasting.

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.

Inborn errors of adrenal steroidogenesis

Congenital adrenal hyperplasia (CAH) refers to a family of inherited disorders of adrenal steroidogenesis in which each disorder is characterized by a specific enzyme deficiency that impairs cortisol production by the adrenal cortex. The enzymes most commonly affected are 21-hydroxylase (21-OH), 11beta-hydroxylase, 3beta-hydroxysteroid dehydrogenase, and less often, 17alpha-hydroxylase/17,20-lyase and cholesterol desmolase. Many of the corresponding genes for the described enzymes have been isolated and characterized, and specific mutations causing CAH have been identified. In classical CAH (simple virilizing and salt wasting forms), androgen excess causes external genital ambiguity in newborn females and progressive postnatal virilization in both sexes. In nonclassical CAH, 21-OHD is partial and occurs with milder symptoms. A deficiency of 11beta-Hydroxylase deficiency results in ambiguous genitalia in the newborn genetic female and androgen excess and hypertension in both males and females. In 3beta-hydroxysteroid deficiency adrenal and gonadal androgen production is deficient resulting in incomplete genital development in genetic males and limited androgen affect in females. Two less frequent causes of CAH 17alpha-Hydroxylase/17,20-lyase and cholesterol desmolase result in external female genitalia in both sexes. Hormonal diagnosis is described for each disorder.

Combined 21-hydroxylase and 11beta-hydroxylase deficiency: patient report and molecular basis

A female newborn (46, XX) with ambiguous genitalia was initially diagnosed by biochemical criteria as having classical congenital adrenal hyperplasia caused by 11beta-hydroxylase deficiency. Shortly after effective treatment was administered, she developed a salt-wasting crisis with severe electrolyte imbalance. DNA analysis revealed a homozygous splice mutation in the second intron of the CYP21 gene, for which both parents were heterozygous. No mutations were found in the entire CYP11B1 gene, thus proving that the 11beta-hydroxylase deficiency was not caused by a gene mutation but rather was a secondary event, possibly due to androgen suppression of 11beta-hydroxylase activity.

Late-onset congenital adrenal hyperplasia in women with hirsutism

Hirsutism in women is a clinical manifestation of excessive production of androgens. The source of the excess androgen may be either the ovaries or the adrenal glands, or increased peripheral conversion of weak androgenic hormones to more potent androgens. Late-onset (non-classic) congenital adrenal hyperplasia is a cause of hirsutism in adult women, but its frequency and the patterns of abnormalities in adrenal hormone secretion are not well understood. The frequency of non-classical adrenal hyperplasia due to deficiencies of 3 beta-hydroxy-delta 5-steroid dehydrogenase, 21-hydroxylase, and 11 beta-hydroxylase among 65 women with hirsutism were determined. All enzyme defects were identified by comparing the patients' hormonal responses to 0.25 mg intravenous bolus of alpha 1-24-ACTH with those of age-matched normal women. The hormones measured in plasma during the ACTH stimulation tests were progesterone, 17-hydroxypregnenolone, 17-hydroxyprogesterone, DHEA-sulfate, androstenedione, testosterone, 11-deoxycortisol, and cortisol. Similarly these hormones were measured after overnight 1 mg oral dexamethasone. Twelve women (18.5%) had 3 beta-hydroxy-delta 5-steroid dehydrogenase deficiency, 24 (37%) 21-hydroxylase deficiency, and 14 (21.5%) 11 beta-hydroxylase deficiency. Women with 21-hydroxylase deficiency also had evidence of a partial deficiency in 11 beta-hydroxylase activity (12 of the 24 patients). Similarly, most (11 of the 14) of the women with 11 beta-hydroxylase deficiency also had evidence of a deficiency in 3 beta-hydroxy-delta 5-steroid dehydrogenase activity. Among the 15 patients with no adrenal biosynthetic defect, eight had high plasma androgen concentrations, and seven had normal concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Secondary biosynthetic defects in women with late-onset congenital adrenal hyperplasia

BACKGROUND AND METHODS

Late-onset (non-classic) congenital adrenal hyperplasia is a cause of hirsutism, menstrual disorders, and infertility, but its frequency and the patterns of abnormalities in adrenal hormone secretion are not well understood. We investigated the frequency and ethnic distribution of nonclassic congenital adrenal hyperplasia due to deficiencies of 3 beta-hydroxy-delta 5-steroid dehydrogenase, 21-hydroxylase, or 11 beta-hydroxylase among 170 Israeli Jewish women with these clinical problems. All enzyme defects were identified by comparing the patients' hormonal responses to a 0.25-mg intravenous bolus dose of alpha 1-24-ACTH with those of 26 age-matched normal women.

RESULTS

Twenty women (12 percent) had 3 beta-hydroxy-delta 5-steroid dehydrogenase deficiency, 18 (10 percent) 21-hydroxylase deficiency (14 homozygous), and 14 (8 percent) 11 beta-hydroxylase deficiency. All the homozygous women with 21-hydroxylase deficiency also had evidence of a partial deficiency in 11 beta-hydroxylase activity. Similarly, most of the women with 11 beta-hydroxylase deficiency also had evidence of a deficiency in 3 beta-hydroxy-delta 5-steroid dehydrogenase. Among the 118 women with no adrenal biosynthetic defect, 38 had high plasma androgen concentrations, and 80 had normal concentrations.

CONCLUSIONS

About one third of Israeli Jewish women with hirsutism, menstrual disorders, or unexplained infertility had nonclassic congenital adrenal hyperplasia. Secondary adrenal biosynthetic defects were frequent in these women and were probably caused by intra-adrenal androgen excess rather than by dual inherited enzymatic deficiencies.

Congenital adrenal hyperplasia due to combined 21- and 11 beta-hydroxylase deficiency

A 26-day-old male was evaluated because on routine follow-up visit his weight was noted to be 3292 g which was not a significant weight gain over his birth weight of 3178 g. His serum electrolytes (NA 107 meq/1, K 8.0 meq/1, Cl 82 meq/1, and HCO2 12 meq/1) were abnormal, urine Na concentration (68 meq/1) was high, and his serum concentrations of 21-deoxycortisol 10, 113 ng/dl (normal 1.2-13), 11-deoxycortisol 15,000 ng/dl (normal 50-250), and 11-deoxycorticosterone 148 ng/dl (normal 2-13) were markedly elevated. Patients having increased levels of the three indicated steroids are diagnosed as having combined 21- and 11 beta-hydroxylase deficiency. On glucocorticoid and mineralocorticoid replacement therapy his electrolytes returned to normal and his weight increased 428 g by the 10th day post initiation of therapy. We hypothesize that the elevated steroid pattern designated as combined 21- and 11 beta-hydroxylase deficiency could result from extraadrenal conversion of 17-hydroprogesterone to 11-deoxycortisol and progesterone to 11-deoxycorticosterone in subjects with adrenal 21-hydroxylase deficiency.

In-vitro steroid production by human granulosa lutein cells in long-term cultures

delta 4 and delta 5 pathway steroidogenesis by human granulosa lutein cells (GLC) in long-term cultures (6-8 days) was investigated under basal (10% serum + medium + GLC) and stimulated (human chorionic gonadotropins (hCG), 100 mIU/ml) conditions. In the delta 4 pathway, 17-hydroxyprogesterone (17-OHP) secretion increased from 160-fold at 48 hours of culture to 360-fold at 144 hours under basal conditions, when compared with the respective controls (concentrations in the 10% serum added to the medium) (p less than 0.005). HCG further augmented 17-OHP production significantly at 96, 144 and 192 hours of culture. Progesterone (P) secretion behaved similarly, and increased from 150-fold at 48 hours to 560-fold at 96 hours when compared with controls, being further stimulated by hCG. In contrast, androstenedione (A) secretion throughout the entire culture period increased only slightly (3-5-fold) under both basal and stimulated conditions, when compared with the respective controls. In the delta 5 pathway, the secretory pattern of 17-hydroxypregnenolone (17-OHPregn) and dehydroepiandrosterone (DHEA) was similar to that observed with A, and both steroids increased only slightly under basal and stimulated conditions, when compared with their respective controls. In conclusion, 17-OHP and P are secreted in very significant amounts during the entire culture period while 17-OHPregn, DHEA and A are secreted in extremely small amounts. These results demonstrate that the delta 5 pathway is inactive in long-term human GLC cultures while the delta 4 pathway is active in certain portions only.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticosteroids: chemistry, synthesis and disturbances in disease

The biosynthesis of adrenocortical steroids is now a reasonably well understood process, which proceeds by discrete, enzyme directed steps from cholesterol to the various hormonal steroids. However, much of our knowledge derives from studies of animal tissues and there is a need for further studies of human glands. In particular, the details of individual enzyme systems, and the extent and significance of compartmentalization of steroid intermediates requires further exploration. The adrenal metabolic errors also merit further study, to clarify some aspects of congenital adrenal hyperplasia and to explain the relationship between biochemical and clinical observations. The advent of immunoassay methods for the measurement of steroid hormone levels in plasma has changed the approach to diagnostic steroid endocrinology, with less emphasis now on the measurement of urinary steroid metabolites, particularly in regard to androgens. The newer and sensitive methods available also allow the assay of steroid hormones in saliva, and the ready availability of this fluid, and the fact that sampling is a non-invasive technique makes salivary steroid assay an attractive alternative to other, traditional methods of investigation requiring blood or urine collection. Inhibitors of steroid biosynthesis and of steroid action have been used with considerable success in diagnostic techniques and to a limited extent in the treatment of steroid disorders. As our understanding of the details of steroid biosynthesis, mechanism of steroid action, and control of steroid secretion improve, further progress in designing clinically useful inhibitors should be possible.