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17-alpha-hydroxylase Deficiency In 3 Siblings - Short-term and Long-term Studies
No full textWe have studied a family (12 members) with 3 patients (2 adult females and 1 pubertal-aged genotypic male) affected by congenital adrenal hyperplasia due to 17-alpha-hydroxylase deficiency, all of whom presented as phenotypically female subjects with lack of sexual development and with hypokalemic hypertension. The baseline hormonal pattern revealed low glucocorticoid levels (17-hydroxyprogesterone, plasma and urinary cortisol, cortisol secretion rate), as well as androgen (testosterone and dehydroepiandrosterone sulfate) and estrogen (17-beta-estradiol) levels, since the defect is present at both adrenal and gonadal levels. As a consequence ACTH, LH, and FSH concentrations were high. Otherwise steroids not requiring 17-alpha-hydroxylation, such as deoxycorticosterone, corticosterone and their 18-hydroxylated compounds, were secreted in excess with the exception of aldosterone whose levels were undetectable; baseline plasma renin activity levels were suppressed. Short-term dexamethasone treatment normalized potassium and reduced blood pressure and the abnormal mineralocorticoid levels. During chronic ACTH suppression with low doses of glucocorticoids (8 years), electrolyte disturbances were corrected, blood pressure was normalized in 2 cases but only reduced in the third; plasma renin activity returned to normal range within four years in all the patients, while urinary aldosterone was normalized only after 8 years of therapy and became partially responsive to posture, ACTH, angiotensin II, and furosemide. The other mineralocorticoids were reduced but remained above the normal range. The HLA-genotyping in all the family members revealed that the gene responsible for 17-alpha-hydroxylase deficiency was not linked to the HLA system. Measurement of plasma steroids (deoxycorticosterone, corticosterone, aldosterone) in this family revealed that the heterozygotes were different from the control population only in their ACTH-stimulated corticosterone levels
[Primary hyperaldosteronism].
No full textThe diagnosis of primary aldosteronism (PA) is based on the finding of the combination of elevated urinary and/or plasma aldosterone and suppressed renin activity in patients with hypertension and hypokalemia. However, PA consists in a number of subsets, and diagnostic criteria for a correct identification of surgically remediable forms are of great interest. The methods and the results concerning our series of 113 patients with primary aldosteronism are presented in this review. Aldosterone producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) were the most frequent forms, 51% and 44% respectively. They had similar BP levels, but hypokalemia was most frequently found in APA. Urinary and upright plasma aldosterone were similar, but supine plasma aldosterone was lower in IHA. Plasma aldosterone response to upright posture and angiotensin II infusion was absent in most cases of APA and present in IHA, but occasionally renin-responsive adenoma were found. Captopril failed to decrease plasma aldosterone in most patients with APA, and in a subgroup of patients with IHA. Patients with adenoma had also higher values of the aldosterone precursor 18-OH-B, and of atrial natriuretic peptide (ANP), probably as a consequence of a greater degree of volume expansion. Among morphological studies, CT scan and adrenal radio-cholesterol scintiscan provided similar results (85% accuracy): adrenal vein catheterization clarified almost all the remaining cases. Among the subsets of PA, 3 familiar cases of dex-suppressible hyperaldosteronism were recognized, with characteristically high levels of aldo, 18-OH-B, 18-OH-cortisol and 18-oxo-cortisol, due to the genetic abnormalities of the 11-18 hydroxylase system.(ABSTRACT TRUNCATED AT 250 WORDS
Acute and chronic effect of nifedipine in primary aldosteronism.
No full textSince calcium entry blocker drugs can interfere with aldosterone secretion in vitro, a similar effect in vivo, in man, has been suggested and partially confirmed. The data available in primary aldosteronism are more controversial. Therefore, we have studied the acute and chronic effect of nifedipine in 7 patients with idiopathic hyperaldosteronism (IHA) and 8 with aldosterone producing adenoma (APA). On 2 different days, 10 mg of nifedipine or placebo were given sublingually to the patients and blood pressure and heart rate were recorded every 5 min. for 60 min. Plasma aldosterone, cortisol, PRA and serum K+ were measured at 0, 30 and 60 min. 5 patients with IHA and 6 with APA received nifedipine 20 mg per os bid for 3 months; the same parameters were evaluated on days 0, 30, 60 and 90; urinary aldosterone was measured on days 0, 30, 60 and 90. BP decreased in both groups both after acute and chronic administration of nifedipine. Plasma aldosterone showed a similar trend either after acute nifedipine or placebo; however, during chronic treatment it was slightly decreased in IHA patients. Cortisol, PRA, urinary aldosterone and K+ remained unchanged. In conclusion, nifedipine is an effective antihypertensive agent also in primary aldosteronism; its aldosterone inhibiting properties are minimal and seem to be present only during long-term therapy in IHA
Atrial natriuretic peptide infusion in primary aldosteronism. Renal, hemodynamic and hormonal effects.
No full textWe have previously shown that a bolus injection of alpha-human atrial natriuretic peptide (alpha-h-ANP) (100 micrograms) in patients with primary aldosteronism induces a transient decrease of blood pressure and a marked natriuresis, but no changes in plasma aldosterone levels. Eight additional cases were studied with a different protocol. Alpha-h-ANP was infused at the dose of 50 ng/kg/min over 1 h, after a bolus of 50 micrograms; saline alone was infused as control. Blood pressure, heart rate, plasma aldosterone, plasma renin activity, cortisol, serum and urinary Na and K and urinary volume were measured. A slight fall in blood pressure, without heart rate changes, was obtained within the first 5 min; this lasted throughout the infusion and for 1 h afterwards. Urinary volume and urinary sodium were significantly higher than controls during the first 2 h, while urinary potassium slightly increased only during the first hour. Plasma renin activity remained suppressed. Plasma aldosterone levels were similar throughout the infusion. Cortisol was not significantly different than placebo except that there was a significant rise after stopping ANP. These data confirm the potent natriuretic effect of ANP infusion and the lack of correlation between ANP induced natriuresis and the effect of ANP on aldosterone in patients with primary aldosteronism
Differential-diagnosis In Primary Aldosteronism
No full textThe diagnosis of primary aldosteronism (PA) is based on the finding of the combination of elevated urinary and/or plasma aldosterone and suppressed renin activity in patients with hypertension and hypokalemia. However, PA consists of a number of subsets, and diagnostic criteria for a correct identification of surgically remediable forms are of great interest. The methods and the results concerning our series of 113 patients with PA are presented in this review. Aldosterone producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) were the most frequent forms, 51 and 44%, respectively. They had similar blood pressure levels, but hypokalemia was most frequently found in APA. Urinary and upright plasma aldosterone were similar, but supine plasma aldosterone was lower in IHA. Plasma aldosterone response to upright posture and angiotensin II infusion was absent in most cases of APA and present in IHA, but occasionally renin-responsive adenoma were found. Captopril failed to decrease plasma aldosterone in most patients with APA, and in a subgroup of patients with IHA. Patients with adenoma also had higher values of the aldosterone precursor 18-hydroxy-corticosterone, and of atrial natriuretic peptide, probably as a consequence of a greater degree of volume expansion. Among morphological studies, CT scan and adrenal radiocholesterol scintiscan provided similar results (85% accuracy): adrenal veins catheterization clarified almost all the remaining cases. Among the subsets of PA, 3 familiar cases of dexamethasone-suppressible hyperaldosteronism were recognized, with characteristically high levels of aldosterone, 18-hydroxy-corticosterone, 18-hydroxy-cortisol and 18-oxo-cortisol, due to the genetic abnormalities of the 11-18 hydroxylase system. Isolated cases of primary adrenal hyperplasia (with all functional tests resulting compatible with APA, but no tumour at surgery) and aldosterone producing carcinoma (1 case) have also been reported in the present study
Long-term Treatment of Mineralocorticoid Excess Syndromes
No full textRecognition of the pathogenesis of secondary forms of hypertension is often considered the key to appropriate choice of treatment. We here present the results of a prolonged clinical follow-up (from I to 20 years) of a large number of patients with mineralocorticoid excess syndromes (MES), including over 100 patients with primary aldosteronism (PA), 3 cases with dexamethasone-suppressible aldosteronism (DSA), 3 cases of apparent mineralocorticoid excess (AME) Type II, and 4 patients with 17-hydroxylase deficiency (17OHDS). The patients with PA have been divided in two subgroups, one of 69 cases followed between 1973 and 1982, and the second of 37 patients studied between 1983 and 1992; 33 further cases were not evaluated due to poor compliance. In group I, 26 patients underwent surgery (23 unilateral adenoma, I primary hyperplasia, 2 bilateral nodular hyperplasia); at 5 years 50% had normal blood pressure, 25% had mild hypertension and 25% had moderate to severe hypertension. Forty-three patients with either adenoma (APA) or idiopathic aldosteronism (IHA) received long-term spironolactone treatment. Among them, 13 required the addition of thiazide and/or beta-blockers, while 13 were switched to an amiloride/thiazide combination (+/- beta blockers) due to side-effects to spironolactone (gynecomastia 6/20 males, menstrual upset or breast pain in 7/23 females). In group II, 12 patients underwent surgery (II adenoma, I primary hyperplasia) with a similar outcome at 3 years as in group I; 25 patients were put on either K canrenoate (II) or Ca++ channel blockers (14) with or without KCI supplementation; in 8 cases these two drugs were combined according to blood pressure levels achieved during the follow-up. ACE inhibitors, thiazide, ketanserin, and ketoconazole were given in selected cases. Gynecomastia occurred only in 2 out of 16 males while on K canrenoate and no side effects were reported in females on the same regimen. The other patients with ACTH-dependent MES were all treated initially with dexamethasone (DEX) at low doses (0.25-1 mg q.d). In all cases potassium remained within the normal limits; blood pressure was not adequately controlled in all 3 cases of DSH and in the oldest patient with 17OHDS and AME Type II, respectively, in spite of the normalization of the hormonal patterns. Ca++ antagonists have been added in these cases, and K canrenoate substituted for DEX in the AME Type II patient. In conclusion, surgical removal or long term treatment of ME with specific antagonists or inhibitors may be inadequate to normalize high blood pressure in almost a half of the patients with MES. This could be due, inter alia, to the persistence of vascular abnormalities, to the coexistence of essential hypertension, or to our only partial understanding of the pathophysiology of some of these syndromes (e.g., IHA and AME)
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Atrial natriuretic peptide in Cushing's disease.
No full textAtrial Natriuretic Peptide (ANF), is secreted by atrial myocytes in response to atrial stretch. Its plasma levels have been found elevated in conditions leading to salt and fluid repletion and consequent atrial distention. Recently, it has been demonstrated that dexamethasone can enhance ANF secretion, by acting on ANF gene expression and mRNA synthesis. High plasma levels of ANF have been observed in normal man after administration of cortisol and ACTH. In the case of glucocorticoid excess, as in Cushing's disease, limited and conflicting data are available. Therefore, we measured ANF basal values and ANF response to postural changes and volume expansion in eight patients with Cushing's disease. In our patients ANF values were higher than normals. ANF responded to volume expansion, 47.8 +/- 5.1 pg/ml before sodium load and 69.9 +/- 7.0 pg/ml after sodium load, and changed minimally after postural manoeuvres, 47.3 +/- 3.2 pg/ml supine and 41.7 +/- 5.1 pg/ml upright. These data indicate that ANF secretion is enhanced in Cushing's disease, and its regulation is partially altered. Since in this condition hypervolemia has not been certainly demonstrated, a direct relationship between elevated ANF and glucocorticoid excess could be suggested
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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