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D Haack

Publications and source records attributed to D Haack.

81 records · Page 5Linked to original sources
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[Variability of corticosterone methyl oxidase (type II) deficiency. Presentation of three case reports].

We report on three cases of Corticosterone Methyl Oxidase Typ II deficiency in two siblings and one boy. All three children were presented with typical symptoms of a saltlosing syndrome (vomiting, poor drinking, weight loss, hypotonia). Hyponatremia and hyperkalemia, low plasma aldosterone concentrations when related to high plasma-renin-activities suggested deficiency in the final steps of aldosterone biosynthesis. Variable degrees of enzyme deficiency and no relation of biochemical findings to the clinical symptoms were observed. Clinical symptoms became less severe with age. Diagnosis of CMO II-deficiency was established by an abnormal high ratio of 18-hydroxycorticosterone to aldosterone, by measurement of their precursors and metabolites in plasma and urine. In one sibling negative values may have been caused by suppression of the renin-angiotensin-system due to high sodium replacement therapy.

Aldosterone↗
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Assessment of hypothalamic-pituitary-adrenocortical axis function in dexamethasone treated very low birth weight infants by a single dose metyrapone test and gas chromatographic mass spectrometric determination of urinary steroids.

In order to assess hypothalamic-pituitary-adrenocortical axis function, we conducted low and single oral dose metyrapone tests (35 mg/kg) in dexamethasone treated very low birth weight infants with bronchopulmonary dysplasia (n = 12). The responses to metyrapone of tetrahydro-11-deoxycortisol (THS) and cortisol metabolites were analyzed by gas chromatography and mass spectrometry in 24-h urinary specimens. For comparative reasons, morning plasma 11-deoxy-cortisol and cortisol were measured by radioimmunoassay before and after metyrapone. No side effects of metyrapone were observed in our patients. In 5 of 12 patients, no urinary THS could be stimulated after metyrapone and most of the other patients had small increases in urinary THS. These findings suggest suppressed or strongly impaired hypothalamic-pituitary-adrenocortical axis function in most patients. While the concentrations of plasma 11-deoxycortisol showed little variation, those of plasma cortisol were grossly different from the respective urinary values. We recommend steroid analysis in 24-h urinary specimens by gas chromatography and mass spectrometry, because urinary steroids provide more information and the highly specific analytical technique is independent of phenomena such as cross reactivity or matrix effects. The low and single oral dose metyrapone test in combination with urinary steroid analysis by gas chromatography and mass spectrometry therefore provides a noninvasive, convenient and safe means of evaluating the integrity of the hypothalamic-pituitary-adrenocortical axis in very low birth weight infants.

Adrenal Cortex↗
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Increased aldosterone-18-glucuronide/tetrahydroaldosterone ratios in pregnancy.

In the present study the aldosterone-18-glucuronide and tetrahydroaldosterone values in 24 hour urine collections of healthy nonpregnant women, women with normal pregnancies and women with pregnancy induced hypertension (PIH) were compared. In pregnancy an elevated excretion of both aldosterone metabolites was found. The Q-ratio (aldosterone-18-glucuronide/tetrahydro-aldosterone+aldosterone-18-glu cur onide) was also increased compared to healthy nonpregnant women. The elevated Q-ratios point out to increased formation of aldosterone-18-glucuronide. This predominantly renal metabolite may reflect greater availability of aldosterone molecules for interaction with mineralocorticoid receptor in the kidney.

Aldosterone↗