Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three patients, one male and two females, in whom the diagnosis of congenital adrenal hyperplasia (CAH) was made in early childhood were studied. The two females were treated with cortisone acetate from the age of 2 and 4 years, respectively, and later they both proved to be fertile. The male patient was only treated sporadically with cortisone acetate until the age of 33 years. He also became fertile when a more consistent treatment with prednisolone was started. The two female patients had a slight hypertension in childhood before the treatment was initiated but became normotensive on treatment. The male patient revealed a blood pressure of180/130 mm Hg at the age of 33 years. In this patient the treatment with prednisolone produced a moderate decrease in the blood pressure, but additional treatment with antihypertensive drugs was needed to make him normotensive. All three patients were originally thought to have a 21-hydroxylase deficiency and the correct diagnosis of an 11 beta-hydroxylase deficiency was first established between the age of 26 and 33 years. It is concluded that an early diagnosis and an uninterrupted treatment with glucocorticoids are important in order to prevent hypertension and infertility problems.
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PMID:Congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency: final diagnosis in adult age in three patients. 735 68

Over a 10-year-period, 78 Saudi children with congenital adrenal hyperplasia were seen at King Khalid University Hospital, Riyadh. Of these, 20 (25.6%) patients from 11 families were 11 beta-hydroxylase deficient. Their mean age was 2.8 years (range 0-10 years). The clinical expression was somewhat severe; pseudoprecocious puberty in males and variable degrees of virilization in females which led to wrong sex assignment in seven (58.3%). Three patients had neonatal salt-wasting before treatment. Moderate to severe hypertension associated with hypokalaemia was present in another six. In four siblings hypertension persisted inspite of adequate hydrocortisone therapy. It is concluded that congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency is relatively frequent among the Saudi Arabian population. In view of the severity of the clinical expression and complications, physicians should be aware of the disease and have a high index of suspicion in order to detect and treat such patients early enough to avoid or minimize the unwanted sequelae.
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PMID:Congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency in Saudi Arabia: clinical and biochemical characteristics. 767 Feb 48

Hypertension is a prominent feature of various endocrine diseases including primary aldosteronism, pheochromocytoma (considered separately in this issue), Cushing's syndrome, adrenal enzymatic deficiencies like 11 beta-hydroxylase, 17 alpha-hydroxylase deficiencies, and congenital or acquired 11 beta-hydroxysteroid dehydrogenase deficiencies. Patients with 11 beta-hydroxylase deficiency cannot convert 11-deoxycortisol or deoxycorticosterone into the active glucocorticoids cortisol and corticosterone, respectively. The increase in the powerful mineralocorticoid deoxycorticosterone, resulting from the enzymatic block, promotes sodium retention, hypertension, and hypokalemia. Females who have the deficiency also show signs of virilization due to the shunting of the precursors to the synthesis of adrenal androgens. Patients with 17 alpha-hydroxylase deficiency present with hypertension and/or hypokalemia, and male members exhibit pseudohermaphroditism with no development of male sexual characteristics. The defect is due to the lack of 17-hydroxylated steroids, which are necessary precursors in the synthesis of androgens and estrogens. The hypertension is due to the accumulation of the mineralocorticoid deoxycorticosterone. The mineralocorticoid receptor derives its specificity from the co-expression of the 11 beta-hydroxysteroid dehydrogenase, which converts the active steroids corticosterone and cortisol to the inactive 11-dehydrocorticosterone and cortisone, preventing their interaction with the receptor. Congenital absence of the 11 beta-hydroxysteroid dehydrogenase or acquired deficiency induced by consuming licorice or its derivatives result in occupancy of the mineralocorticoid receptor by cortisol and corticosterone, and production of mineralocorticoid-type hypertension.
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PMID:Endocrine causes of hypertension. 777 21

The most active corticosteroids are 11 beta-hydroxylated. Humans have two isozymes with 11 beta-hydroxylase activity that are respectively required for cortisol and aldosterone synthesis. CYP11B1 (11 beta-hydroxylase) is expressed at high levels and is regulated by ACTH, whereas CYP11B2 (aldosterone synthase) is normally expressed at low levels and is regulated by angiotensin II. In addition to 11 beta-hydroxylase activity, the latter enzyme has 18-hydroxylase and 18-oxidase activities and thus can synthesize aldosterone from deoxycorticosterone. Insights into the normal functioning of these enzymes are gained from studies of disorders involving them. Mutations in the CYP11B1 gene cause steroid 11 beta-hydroxylase deficiency, a form of congenital adrenal hyperplasia characterized by signs of androgen excess and by hypertension. Mutations in CYP11B2 result in aldosterone synthase (corticosterone methyloxidase) deficiency, an isolated defect in aldosterone biosynthesis that can cause hyponatremia, hyperkalemia, and hypovolemic shock in infancy and failure to thrive in childhood. These are both recessive disorders. Unequal crossing over between the CYP11B genes can generate a duplicated chimeric gene with the transcriptional regulatory region of CYP11B1 but sufficient coding sequences from CYP11B2 so that the encoded enzyme has aldosterone synthase (i.e. 18-oxidase) activity. This results in aldosterone biosynthesis being regulated by ACTH, a condition termed glucocorticoid-suppressible hyperaldosteronism. This form of genetic hypertension is inherited in an autosomal dominant manner.
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PMID:Disorders of steroid 11 beta-hydroxylase isozymes. 798 80

Steroid 11 beta-hydroxylase deficiency is the second most frequent cause of congenital adrenal hyperplasia, the inherited inability to synthesize cortisol. About two thirds of patients with this disorder have hypertension, presumably due to elevated levels of deoxycorticosterone or other metabolites. Signs of androgen excess also often are prominent. This disease is caused by mutations in the CYP11B1 gene, which encodes a mitochondrial cytochrome P450 enzyme. The main treatment is glucocorticoid replacement, which suppresses excessive secretion of mineralocorticoids and androgens by the adrenal cortex.
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PMID:Steroid 11 beta-hydroxylase deficiency and related disorders. 807 Apr 25

The human P450c17 alpha gene (CYP17) is a single copy gene located in chromosome 10, consisting of 8 exons and 7 introns. 17 alpha-Hydroxylase/17,20-lyase deficiency is one of two hypertensive forms of congenital adrenal hyperplasia and is inherited as an autosomal recessive trait; although rare, it probably exists with twice the frequency of the 11 beta-hydroxylase deficiency. Deficient 17 alpha-hydroxylation of pregnenolone and progesterone and subsequent deficiency of the cleavage of the C-17,20 carbon bond result in the absence of sex hormone formation in both the adrenal glands and the gonads, causing hypogonadism and male pseudohermaphroditism. Elevated and glucocorticoid-suppressible levels of the ZF 17-deoxysteroids--DOC and corticosterone--as well as their 18-hydroxylated products--18-OHDOC and 18-OHB (in addition to 19-nor-DOC)--are responsible for hypertension, hypokalemia, and renin and aldosterone suppression. A few cases, reported primarily among Japanese families, have basal hyperaldosteronism, an enigmatic condition that still demands adequate explanation. Like other forms of congenital adrenal hyperplasia, treatment of 17 alpha-hydroxylase deficiency consists of replacement doses of glucocorticoid hormones and supplemental estrogen therapy in the young adult patient. Heterozygotes may be detected by slightly exaggerated responses of some or all the ZF 17-deoxysteroids to ACTH stimulation, and by the elevated ratio of total urinary metabolites of corticosterone to the total metabolites of cortisol.
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PMID:Disorders of steroid 17 alpha-hydroxylase deficiency. 807 Apr 26

In its classical form, congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency is characterized by hypertension and abnormal sexual development. Suppression of ACTH secretion by means of administering glucocorticoids fulfills the therapeutic goal of reducing blood pressure and decreasing androgen production. The present report describes the case of a patient suffering from congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency who developed an acute adrenal crisis, unprovoked by stress, following interruption of glucocorticoid replacement therapy. It is suggested that patients on a suppressive dose of glucocorticoids for adrenal hyperplasia are at increased risk for acute adrenal insufficiency if therapy is interrupted, and that deoxycorticosterone (DOC) in the absence of a glucocorticoid is insufficient to prevent manifestations of adrenal crisis.
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PMID:Acute adrenal crisis complicating hypertensive congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. 844 9

Classic congenital 11-beta-hydroxylase deficiency is a relatively uncommon cause of congenital adrenal hyperplasia and is characterized by virilization and often hypertension. The association of skeletal abnormalities (short metatarsal bone) and pulmonary stenosis in a patient with 11-beta-hydroxylase has been reported by our group. In this report, three new patients with congenital adrenal hyperplasia due to a defect in 11-beta-hydroxylase enzyme with short fourth metatarsals are described. Gynecomastia was noted in one patient. The relative rarity of 11-beta-hydroxylase deficiency and the association of skeletal abnormalities suggest the possibility that this is more than a mere coincidental finding.
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PMID:Congenital adrenal hyperplasia due to 11-beta-hydroxylase deficiency with skeletal abnormalities. 879 41

Steroid 11 beta-hydroxylase deficiency is the second most common cause of congenital adrenal hyperplasia, the inherited inability to synthesize cortisol. Severely affected patients carry mutations in the CYB11B1 gene that destroy enzymatic activity. Such patients have signs of androgen excess and usually have hypertension. Mild or non-classic 11 beta-hydroxylase deficiency has been reported previously but not studied genetically. In this study we report analysis of the CYP11B1 genes of three patients thought to suffer from non-classic 11 beta-hydroxylase deficiency. Mutations were detected in the CYP11B1 genes of two patients. One was a compound heterozygote for missense mutations N133H and T319M, whereas the other carried a nonsense mutation (Y423X) on one allele and a missense mutation (P42S) on the other. All three missense mutations affected enzymatic activity when expressed in vitro. No mutations were detected in the coding regions or intron-exon boundaries of the CYP11B1 genes of the other putative non-classic patient. In addition, we were unable to detect CYP11B1 mutations in two hirsute women with mildly elevated levels of 11 beta-hydroxylase precursors who had previously been identified in a screening study of patients in a reproductive endocrinology clinic. We conclude that nonclassic 11 beta-hydroxylase deficiency is a rare disorder. It is not a significant cause of hyperandrogenism in women and relatively stringent criteria should be used to prevent its misdiagnosis.
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PMID:CYP11B1 mutations causing non-classic adrenal hyperplasia due to 11 beta-hydroxylase deficiency. 930 60

Aldosterone participates in blood volume and serum potassium homeostasis, which in turn regulate aldosterone secretion by the zona glomerulosa of the adrenal cortex. Autonomous aldosterone hypersecretion leads to hypertension and hypokalemia. Improved screening techniques have led to a re-evaluation of the frequency of primary aldosteronism among adults with hypertension, recognizing that normokalemic cases are more frequent than was previously appreciated. The genetic basis of glucocorticoid remediable aldosteronism has been elucidated and adequately explains most of the pathophysiologic features of this disorder. A new form of familial aldosteronism has been described, familial hyperaldosteronism type II; linkage analysis 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 features of aldosterone hypersecretion may be due to non-aldosterone-mediated mineralocorticoid excess. These include two causes of congenital adrenal hyperplasia (11 beta-hydroxylase deficiency and 17 alpha-hydroxylase deficiency), the syndrome of apparent mineralocorticoid excess (AME) due to 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) deficiency, primary glucocorticoid resistance, Liddle's syndrome due to activating mutations of the renal epithelial sodium channel, and exogenous sources of mineralocorticoid, such as licorice, or drugs, such as carbenoxolone. The features of mineralocorticoid excess are also often seen in Cushing's syndrome. Hypoaldosteronism may lead to hypotension and hyperkalemia. Hypoaldosteronism may be due to inadequate stimulation of aldosterone secretion (hyporeninemic hypoaldosteronism), defects in adrenal synthesis of aldosterone, or resistance to the ion transport effects of aldosterone, such as are seen in pseudohypoaldosteronism type I (PHA I). PHA I is frequently due to mutations involving the amiloride sensitive epithelial sodium channel. Gordon's syndrome (PHA type II) is due to resistance to the kaliuretic but not sodium reabsorptive effects of aldosterone for which the genetic basis is still unknown. This review aims to provide a survey of the clinical disorders of aldosterone excess and deficiency and their clinical management, with a focus on primary aldosteronism and isolated aldosterone deficiency.
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PMID:Hyper- and hypoaldosteronism. 1023 50


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