1/19. Does kidney transplantation normalise cortisol metabolism in apparent mineralocorticoid excess syndrome?The syndrome of apparent mineralocorticoid syndrome (AME) results from defective 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2). This enzyme is co-expressed with the mineralocorticoid receptor (MR) in the kidney and converts cortisol to its inactive metabolite cortisone. Its deficiency allows the unmetabolized cortisol to bind to the MR inducing sodium retention, suppression of PRA and hypertension. Thus, the syndrome is a disorder of the kidney. We present here the first patient affected by AME cured by kidney transplantation. Formerly, she was considered to have a mild form of the syndrome (Type II), but progressively she developed renal failure which required dialysis and subsequent kidney transplantation. To test the ability of the transplanted kidney to normalise the patient's cortisol metabolism, we gave, in two different experiments, 25 and 50 mg/day of cortisone acetate or 15 and 30 mg/day of cortisol after inhibition of the endogenous cortisol by synthetic glucocorticoid (methylprednisolone and dexamethasone). The AME diagnostic urinary steroid ratios tetrahydrocortisol 5alphatetrahydrocortisol/tetrahydrocortisone and cortisol/cortisone were measured by gas chromatography/mass spectrometry. Transplantation resulted in lowering blood pressure and in normalization of serum K and PRA. After administration of a physiological dose of cortisol (15 mg/day), the urinary free cortisol/cortisone ratio was corrected (in contrast to the A-ring reduced metabolites ratio), confirming that the new kidney had functional 11beta-HSD2. This ratio was abnormally high when the supra-physiological dose of cortisol 30 mg/day was given. After cortisone administration, the tetrahydrocortisol 5alphatetrahydrocortisol/tetrahydrocortisone ratio resulted normalised with both physiological and supra-physiological doses, confirming that the hepatic reductase activity is not affected. As expected, the urinary free cortisol/cortisone ratio was normal with physiological, but increased after supra-physiological doses of cortisone. The described case indicates a normalisation of cortisol metabolism after kidney transplantation in AME patient and confirms the supposed pathophysiology of the syndrome. Moreover, it suggests a new therapeutic strategy in particularly vulnerable cohorts of patients inadequately responsive to drug therapy or with kidney failure.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/19. warfarin therapy for an octogenarian who has atrial fibrillation.In north america, atrial fibrillation is associated with at least 75 000 ischemic strokes each year. Most of these strokes occur in patients older than 75 years of age. The high incidence of stroke in very elderly persons reflects the increasing prevalence of atrial fibrillation that occurs with advanced age, the high incidence of stroke in elderly patients, and the failure of physicians to prescribe antithrombotic therapy in most of these patients. This failure is related to the increased risk for major hemorrhage with advanced age, obfuscating the decision to institute stroke prophylaxis with antithrombotic therapy.This case-based review describes the risk and benefits of prescribing antithrombotic therapy for a hypothetical 80-year-old man who has atrial fibrillation and hypertension, and it offers practical advice on managing warfarin therapy. After concluding that the benefits of warfarin outweigh its risks in this patient, we describe how to initiate warfarin therapy cautiously and how to monitor and dose the drug. We then review five recent randomized, controlled trials that document the increased risk for stroke when an international normalized ratio (INR) of less than 2.0 is targeted among patients with atrial fibrillation. Next, we make the case that cardioversion is not needed for this asymptomatic patient with chronic atrial fibrillation. Instead, we choose to leave the patient in atrial fibrillation and to control his ventricular rate with atenolol. Later, when the INR increases to 4.9, we advocate withholding one dose of warfarin and repeating the INR test. Finally, when the patient develops dental pain, we review the analgesic agents that are safe to take with warfarin and explain why warfarin therapy does not have to be interrupted during a subsequent dental extraction.- - - - - - - - - - ranking = 0.0036672235931051keywords = extraction (Clic here for more details about this article) |
3/19. Combined strabismus and phacoemulsification cataract surgery: a useful option in selected patients.PURPOSE: To evaluate the role of combined strabismus and phacoemulsification cataract extraction in patients with symptomatic cataract and strabismus. methods: Four procedures of combined strabismus and cataract surgery are described in 3 elderly patients with strabismus of differing aetiologies. Two patients underwent one procedure; the other patient underwent two combined procedures, one to each eye. RESULTS: The visual acuity improved in all 3 patients. Post-operative alignment of the visual axis was achieved which allowed resolution of symptomatic diplopia in patient 1, functional binocular single vision in patient 2 and a noticeably reduced compensatory head posture in patient 3. CONCLUSIONS: Combined strabismus and cataract surgery is a safe procedure that can optimise visual alignment and improve visual acuity with a minimum number of operations.- - - - - - - - - - ranking = 0.0036672235931051keywords = extraction (Clic here for more details about this article) |
4/19. apolipoprotein a-i deficiency with accumulated risk for CHD but no symptoms of CHD.We evaluated a 69-year-old Japanese woman with apolipoprotein (apo) A-I deficiency, high levels of low-density lipoprotein (LDL)-cholesterol, hypertension and impaired glucose tolerance. The patient had corneal opacity, but neither xanthomas, xanthelasma, nor tonsillar hypertrophy. She was not symptomatic for coronary heart disease (CHD), and had normal electrocardiograms at rest and exercise using a cycle ergometer. She had severely reduced levels of high-density lipoprotein (HDL)-cholesterol (0.10-0.18 mmol/l) and no apo A-I (<0.6 mg/dl). LDL-cholesterol and apo B as well as apo E were increased even under treatment with 10 mg pravastatin per day. Gel filtration chromatography revealed that in addition to VLDL and LDL fractions, she had apo A-II rich and apo E rich fractions, which were present in the HDL fraction separated by ultracentrifugation. A cytosine deletion was identified by genomic dna sequencing of the apo A-I gene of the patient at the third base of codon 184 in the fourth exon, which led to a frame shift mutation and early termination at codon 200. This patient is the oldest among those with apo A-I deficiency reported in the literature, and she had no symptoms of CHD despite the accumulated risk for the disease.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
5/19. Redistribution of diltiazem in the early postmortem period.We determined tissue distribution of diltiazem after it was used to treat hypertension in two cases. The postmortem interval was 16 h in both cases. diltiazem was isolated using liquid-liquid extraction, and it was identified and quantitated using gas chromatography-mass spectrometry (GC-MS) and GC, respectively. In one case, diltiazem concentrations in the lungs and pulmonary vessel blood were 62-82 and 27-30 times higher than right femoral blood, respectively. Although blood was not obtained from the left cardiac chambers, aortic blood showed a 10-times higher level of diltiazem than right femoral venous blood. diltiazem concentration in blood in the right cardiac chambers was 3.6 times higher than that in right femoral venous blood. In another case, diltiazem concentrations in the lungs were 7.4-7.6 times higher than right femoral venous blood. Blood in the pulmonary arteries, pulmonary veins, left cardiac chambers, and aorta showed 2.0-3.1 times higher levels of diltiazem than right femoral venous blood. Blood in the right cardiac chambers displayed only 1.3 times higher level of diltiazem than right femoral venous blood. Our results strongly suggest that diltiazem accumulated in the lungs and was rapidly redistributed into pulmonary venous blood and then into the left cardiac chambers.- - - - - - - - - - ranking = 1.0036672235931keywords = chromatography, extraction (Clic here for more details about this article) |
6/19. Hypertensive virilizing adrenal hyperplasia with minimal impairment of synthetic route to cortisol.One of the first described cases of hypertensive virilizing adrenal hyperplasia (VAH) (pediatrics 8: 805, 1951) has been followed from age 2 1/2 until age 26. blood pressure as an infant was 150/90, and at age 25 was 220/160. During childhood the patient was lost to follow-up for prolonged periods, and received no therapy from age 20 to 25. At this time 24 h urinary excretion of 17-ketosteroids was 89 mg; tetrahydro 11-deoxycortisol (tetrahydro S), 47 mg and pregnanetriol 5.7 mg. Hourly measurements of several plasma steroids utilizing sephadex LH 20 chromatography and competitive protein binding were made during 24 h; concentration ranges were made during 24 h; concentration ranges were as follows (mug/100 ml): 11-deoxycortisol 8-40; cortisol 0-48; corticosterone 0-15; deoxycorticosterone 1-18. plasma cortisol, especially showed a significiant morning impairment, but reached normal and even markedly elevated levels during the day and early evening. Urinary cyclic amp per 24 h ranged from 5.3 to 11.6 n mol/mg creatinine before therapy, and was 1.9 n mol after therapy. The results suggest either the formation of an alternate pathway to cortisol synthesis, or the existence of a form of VAH with two independent 11-B hydroxylating systems, exhibiting only minimal impairment of the synthetic route to cortisol. The latter would support the presence of two independent 11-B hydroxylating systems in the normal human adrenal. This has been suggested by Zachmann et al. (J Clin Endocrinol Metab 33: 501, 1971) to be true in infancy. Our observations on an adult indicate that these two systems may not be transitory, but persist into adulthood.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
7/19. A hypertensive emergency following cataract extraction and cornea transplantation.We report a hypertensive crisis resulting from an unsuspected pheochromocytoma following a routine anterior segment procedure. Although pheochromocytomas are rare, ophthalmologists should be aware of the signs and symptoms of this tumor as well as of the possible role that postoperative administration of timolol may have in pheochromocytoma-triggered hypertension.- - - - - - - - - - ranking = 0.014668894372421keywords = extraction (Clic here for more details about this article) |
8/19. Delayed microhyphaema with intraocular lenses: a retrospective study of eight patients.Eight patients with delayed microhyphaema were identified from a computer data base of 1209 patients who had had cataract extraction with Binkhorst 4-loop intraocular lens insertion. Five cases were recurrent. The cases were examined to try and identify an underlying cause. No single cause was identified, but trauma, hypertension, and oral anticoagulants were found to be associated. Some episodes were asymptomatic. The wide variety of surgical technique and style of lens with which this complication has been reported implies multiple causative factors. The source of the bleeding and its management are discussed.- - - - - - - - - - ranking = 0.0036672235931051keywords = extraction (Clic here for more details about this article) |
9/19. spironolactone-reversible rickets associated with 11 beta-hydroxysteroid dehydrogenase deficiency syndrome.A 7-year-old girl had growth retardation, hypertension, and hypokalemic alkalosis. Baseline serum aldosterone concentration and plasma renin activity were low and unresponsive to sodium deprivation and to orthostatic changes. Baseline serum progesterone, 17-hydroxyprogesterone, 11-deoxycortisol, and cortisol levels were normal and adequately responsive to ACTH stimulation. No steroid was found abnormally elevated. A diagnosis of 11 beta-hydroxysteroid dehydrogenase deficiency was established on the basis of elevated urinary tetrahydrocortisol plus allotetrahydrocortisol/tetrahydrocortisone ratio, determined by gas chromatography-mass spectrometry. Evaluation of bone mineral metabolism and parathyroid function, and skeletal radiographs, revealed the presence of rickets and secondary hyperparathyroidism. Treatment with spironolactone alone for 2 months corrected hypertension, hypokalemic alkalosis, and all laboratory and radiologic evidence of rickets and hyperparathyroidism, resulting in acceleration of growth rate. The response to spironolactone suggests that a hypermineralocorticoid state is responsible for the hypertensive syndrome and that rickets and hyperparathyroidism could be a consequence of excess mineralocorticoid activity.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
10/19. A phaeochromocytoma presenting with Cushing's syndrome associated with increased concentrations of circulating corticotrophin-releasing factor.The case is described of a 61-year-old male who presented with hypertension and Cushing's syndrome which resolved on excision of a unilateral adrenal mass. histology of the tumour revealed a benign phaeochromocytoma which immunostained for corticotrophin-releasing factor (CRF-41) but not for ACTH. Preoperative plasma concentrations of immunoreactive CRF-41 were increased, and gradients for both CRF-41 and ACTH were demonstrated across the tumour. Post-operatively, CRF-41 was undetectable in plasma. The tumour contained high concentrations of immunoreactive CRF-41 which co-eluted with synthetic human CRF-41 on reversed-phase high-performance liquid chromatography. Tumour CRF-41 stimulated the release of ACTH in a dose-dependent manner from isolated rat anterior pituitary cells. We conclude that this tumour secreted CRF-41 and ACTH and had the capacity to produce ACTH-dependent Cushing's syndrome directly by secreting ACTH and indirectly by secreting CRF-41 to stimulate ACTH secretion from the anterior pituitary.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
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