Biomedical subjects

Lorena Mosso

Publications and source records attributed to Lorena Mosso.

8 recordsLinked to original sources

PubMed2006

Comparison of confirmatory tests for the diagnosis of primary aldosteronism.

CONTEXT: Primary aldosteronism (PA) is the most frequent form of secondary hypertension, accounting for up to 5-10% of all hypertensive patients, and the diagnosis of PA can present an important challenge for the clinician. After a positive screening test, the diagnosis is confirmed by a suppression test, often an iv saline load test (SLT) or a fludrocortisone suppression test (FST). The FST is considered by many to be the most reliable but is more complex and expensive. OBJECTIVE AND DESIGN: Our objective was to compare the specificity of SLT with FST for the diagnosis of PA. PATIENTS AND SETTING: The study included 100 hypertensive patients referred to hypertension units with suspected PA after the screening test. INTERVENTION: All patients underwent FST and SLT. MAIN OUTCOME MEASURES: We assessed plasma aldosterone concentrations (PAC) before and after FST and SLT. RESULTS: After iv SLT, 10.4% of the PA patients were negative and 16.1% of patients with essential hypertension were positive after SLT; that is, a correct diagnosis with SLT was obtained in 88% of patients compared with FST. PAC after SLT and PAC after FST were highly correlated (P < 0.0001). Receiver operator characteristic curve analysis demonstrated that the best cutoff for PAC after SLT was 5 ng/dl. Patients with aldosterone-producing adenoma displayed a smaller reduction of PAC compared with patients with bilateral adrenal hyperplasia; a PAC after SLT greater than 6 ng/dl identified all patients eventually diagnosed as having aldosterone-producing adenoma. CONCLUSIONS: This study demonstrates that the iv SLT is a reasonably good alternative to the more expensive and complex FST for the diagnosis of PA after a positive screening test.

Adenoma↗

PubMed2005

[Pathological characteristics of thyroid microcarcinoma. A review of 402 biopsies].

BACKGROUND: Thyroid microcarcinoma is a tumor of 10 mm or less, that should have a low risk of mortality. However, a subgroup of these carcinomas is as aggressive as bigger tumors. AIM: To describe the pathological presentation of these tumors, and compare them with larger tumors. MATERIAL AND METHODS: All pathological samples of thyroid carcinoma that were obtained between 1992 and 2003, were studied. In all biopsies, the pathological type, tumor size, the focal or multifocal character, the presence of lymph node involvement and the presence of lymphocytic thyroiditis or thyroid hyperplasia, were recorded. RESULTS: One hundred eighteen microcarcinomas and 284 larger tumors were studied. The mean age of patients with microcarcinoma and larger tumors was 42.7+/-14 and 49.3+/-16 years respectively (p <0,001) and 83% were female, without gender differences between tumor types. Mean size of microcarcinomas was 8.6 mm and 116 (98%) were papillary carcinomas. Of these, 109 (94%) were well differentiated and seven (6%) were moderately differentiated. Thirty six (31%) were multifocal and in 10 (8,6%), there was lymph node involvement. The mean size of larger tumors was 23.8 mm and 241 (85%) were papillary carcinomas. Of these, 200 (83%) were well differentiated, and 41 (17%) were moderately differentiated. Eighty five (35%) were multifocal and in 44 (18%) there was lymph node involvement. The prevalence of thyroiditis and hyperplasia was significantly higher among microcarcinomas than in larger tumors (15 and 2.5%, respectively, p <0.001, for the former; 32.4 and 1.7%, respectively, p <0.001, for the latter). CONCLUSIONS: In this series, one third of microcarcinomas were multifocal and 10% had lymph node involvement. Therefore, the aggressiveness of these tumors is higher than what is reported in the literature and they should be treated with total thyroidectomy.

Adult↗

PubMed2005

[Thyroid microcarcinoma with an aggressive evolution. Report of one case].

The treatment of papillary thyroid carcinoma of less than 10 mm diameter is a matter of controversy. The incidental finding of papillary microcarcinomas in autopsies is frequent and some authors postulate that these tumors are biologically inactive and should only be observed. We report a 21 years old woman with a papillary thyroid cancer of 6 x 5 x 5 mm and bilateral paratracheal metastases, that was subjected to a total thyroidectomy. She received 200 mCi of radioiodine. Two years after surgery, a new nodule of 9.6 mm diameter was detected by ultrasound, that was treated with a new dose of 200 mCi of radioiodine. One year later a suprasternal mass of 2 cm diameter and 3 enlarged lymph nodes were detected. She was subjected to a surgical lymph node dissection of the neck and the biopsy confirmed the presence of cancer. She received a new dose of 300 mCi of radioiodine. The mother of the patient had a 7 mm thyroid nodule that was also a papillary carcinoma.

Adult↗

PubMed2004

Increased diagnosis of primary aldosteronism, including surgically correctable forms, in centers from five continents.

Primary aldosteronism (PA) is a common form of endocrine hypertension previously believed to account for less than 1% of hypertensive patients. Hypokalemia was considered a prerequisite for pursuing diagnostic tests for PA. Recent studies applying the plasma aldosterone/plasma renin activity ratio (ARR) as a screening test have reported a higher prevalence. This study is a retrospective evaluation of the diagnosis of PA from clinical centers in five continents before and after the widespread use of the ARR as a screening test. The application of this strategy to a greater number of hypertensives led to a 5- to 15-fold increase in the identification of patients affected by PA. Only a small proportion of patients (between 9 and 37%) were hypokalemic. The annual detection rate of aldosterone-producing adenoma (APA) increased in all centers (by 1.3-6.3 times) after the wide application of ARR. Aldosterone-producing adenomas constituted a much higher proportion of patients with PA in the four centers that employed adrenal venous sampling (28-50%) than in the center that did not (9%). In conclusion, the wide use of the ARR as a screening test in hypertensive patients led to a marked increase in the detection rate of PA.

Aldosterone↗

PubMed2004

[Free urinary cortisol is elevated in patients with low-renin essential hypertension].

BACKGROUND: Glucocorticoids play a key role in blood pressure (BP) control and are associated with hypertension in patients with Cushing's syndrome. A number of reports indicate that cortisol (F) may be involved in etiology of essential hypertension (EH). F can bind to the mineralocorticoid receptor, triggering both sodium and water reabsorption in kidney, increase BP and cause renin suppression. AIM: To evaluate urinary free cortisol (UFF) excretion as a potential intermediate phenotype of essential hypertension and correlate F level with plasma renin activity (PRA) and serum aldosterone (SA). PATIENTS AND METHODS: We recruited 132 EH patients and 16 normotensive healthy controls. Blood samples and 24 hours urine were collected for PRA, SA and UFF analysis. Differences in UFF excretion between sexes were normalized by urinary creatinine (Creat) excretion. The upper limit of UFF/Creat was determined in normotensives considering the mean value plus 2 standard deviations. According to this value, subjects were classified as having high or normal UFF. RESULTS: In EH patients and in normotensives, the UFF/Creat was 36.9 +/- 17.0 microg/gr and 30.9 +/- 8.8 microg/gr, respectively. The upper limit was set at 48.5 microg/gr. A high UFF/Creat was found in 20/132 EH (15%) patients and 0/16 normotensive subjects. EH patients with high UFF showed lower PRA levels than patients with normal cortisol levels (0.78 +/- 0.47 vs. 1.13 +/- 0.66 ng/ml x h, respectively, p=0.027) and lower SA values (4.52 +/- 1.65 vs 6.34 +/- 3.37 ng/dl, respectively, p=0.018). There was a negative correlation between UFF and PRA (r=-0.176, p=0.044) and between UFF and SA (r=-0.183, p=0.036). CONCLUSIONS: We have identified a subgroup of EH patients with increased UFF excretion. Patients with the highest UFF showed lower renin and aldosterone levels. These data suggest a potential influence of cortisol in the genesis of hypertension.

Aldosterone↗

PubMed2003

Primary aldosteronism and hypertensive disease.

Recent studies in hypertensive populations that have used the serum aldosterone (SA) to plasma renin activity (PRA) ratio as a screening test have demonstrated a high prevalence of primary aldosteronism (PA). This frequency is higher than that previously described when hypokalemia was used as a screening tool. However, other factors, such as the characteristics of hypertensive disease, could also influence the prevalence of PA. We studied 609 essential hypertensive patients, classified according to the Joint National Committee VI (JNC VI), in 3 different stages depending on the severity of their hypertensive disease. We measured SA and PRA and calculated the SA-PRA ratio for all patients. An SA-PRA ratio >25 was detected in 63 of 609 patients, and the fludrocortisone test confirmed the PA diagnoses in 37 of 609 (6.1%) cases. PA prevalence according to hypertension stage was as follows: stage 1, 6 of 301 cases (1.99%); stage 2, 15 of 187 cases (8.02%); and stage 3, 16 of 121 cases (13.2%). PA patients were slightly younger than the other hypertensive patients (48.4+/-10.5 vs 53.6+/-10.2 years; P<0.05). Serum potassium levels were normal in 36 of 37 PA patients; only 1 patient had minor hypokalemia. Computed tomography scans showed bilateral adrenal enlargement in 7 and an adrenal nodule in 2 cases. In summary, we found a high frequency of PA in essential hypertensives classified in stages 2 and 3 according to the JNC VI. The low frequency of computed tomography scan abnormalities and hypokalemia suggests that the diagnosis for most PA patients corresponds to attenuated forms of the disease.

Aldosterone↗

PubMed2002

Primary aldosteronism.

Primary aldosteronism is a potentially curable form of hypertension. Recent studies using the plasma aldosterone to plasma renin activity ratio as screening test in hypertensive populations have demonstrated a high prevalence of primary aldosteronism close to 10%. This frequency is clearly higher than the classically described when hypokalemia is used as the screening method. The most common subtypes of primary aldosteronism are idiopathic aldosteronism and aldosterone-producing adenoma. Other causes are glucocorticoid-remediable aldosteronism, unilateral or primary adrenal hyperplasia and adrenal carcinoma. The diagnosis of primary aldosteronism is advocated to confirm the autonomy of aldosterone secretion from the renin-angiotensin system and to differentiate the clinical subtypes of the disease. This article reviews the new data about prevalence, diagnosis criteria and describes the clinical, biochemical and genetic characteristics of the different subtypes of the disease. We also discuss the treatment, and the differential diagnosis with other hyper-mineralocorticoid states.

Aldosterone↗

PubMed2002

[11 beta-hydroxysteroid dehydrogenase type 2 activity in Chilean patients with hypertension].

BACKGROUND: Half of hypertensive patients with low plasma renin activity have a primary hyperaldosteronism. Among the remaining half, 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta HSD2) deficiency plays an important role. This enzyme catalyzes the conversion of cortisol to cortisone, avoiding the interaction of cortisol with the mineralocorticoid receptor. If the enzyme fails, cortisol will stimulate sodium and water reabsorption and increase blood pressure. AIM: To determine biochemical alterations, suggestive of 11 beta HSD2 deficiency, in low-renin hypertensive patients. PATIENTS AND METHODS: Twenty eight hypertensive patients with a plasma renin activity of less than 0.5 ng/ml/h and with a plasma aldosterone of less than 5 ng/dl were studied. Twenty eight normotensive patients were studied as controls. Serum cortisol (RIA), cortisone (ELISA) and the serum cortisol/cortisone ratio were determined in all of them, between 9 and 10 AM. Measurements were confirmed by high pressure liquid chromatography. The serum cortisol/cortisone ratio was considered abnormal when its Ln (cortisol/cortisone) value was over 2 standard deviations of the mean. RESULTS: Serum cortisol was higher in hypertensive subjects than in controls (11.1 +/- 3.3 and 9.2 +/- 2.8 micrograms/dl, respectively; p < 0.05). No differences were observed in serum cortisone (3.4 +/- 1.3 and 3.7 +/- 1.2 micrograms/dl, respectively). Four hypertensive subjects had an abnormally high Ln (cortisol/cortisone) value (1.86; 1.73; 2.07 and 2.01, considering a normal value of less than 1.61). CONCLUSIONS: Four of 28 hypertensive subjects with low plasma renin activity and aldosterone had biochemical alterations suggestive of 11 beta HSD2 deficiency.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗