Utilidad e interpretación de la biopsia tiroidea por punción con aguja fina / Use and interpretation of fine needle aspiration biopsy of thyroid nodules

Fine needle thyroid biopsy is a safe and cost effective diagnostic method for thyroid nodules. Its use has reduced the number of unnecessary thyroidectomies, performed to excise thyroid nodules. Since it is an invasive diagnostic method, its indications should be specified according to ultrasonographic criteria. The massive use of fine needle biopsies increase the number of unsatisfactory samples and indeterminate results. Although it is possible to obtain biopsies from exceedingly small nodules, the clinical significance of these small carcinomas is not yet defined. Ultrasonography, mmunohistochemical markers such as citokeratin, 19, HBME-1, galectin 3) and genetic determinants such as oncogene RET/PTC, 1, 2, 3, RAS oncogene and BRAF V600E mutation along with clinical follow up, will readily identify those patients that are benefited with fine needle biopsies.

Alta frecuencia de patología tiroidea funcional y autoinmune en mujeres embarazadas chilenas catalogadas como sanas / High frequency of functional and autoimmune thyroid disease in women classified as healthy Chilean pregnant

Background: Untreated functional thyroid diseases are a risk factor for maternal and fetal complications during pregnancy. Aim: To determine the frequency of functional or autoimmune thyroid disease in healthy women during the first trimester of pregnancy. Subjets and Methods: healthy pregnant women attending a routine consult during their first trimester of pregnancy were studied. Thyroid stimulating hormone (TSH), total and free thyroxin (T4) anti-thyroid peroxidase (TPO) antibodies and spot urine iodine levels were measured. The reference ranges provided by the Atlanta Georgia Consensus in 2004 were used as normal values. A urine iodine concentration < 150 ug/L was considered low. Results: One hundred women age 30 +/- 5 years with a mean gestational age of 8,8 +/- 1,9 weeks, were studied. The frequencies of subclinical hypothyroidism, clinical hypothyroidism, isolated low thyroxin lecels, high antiTPO antibodies and low urine iodine levels were 19, 2, 3, 13 and 15 percent, respectively. Women with high TSH levels had lower total and free T4 levels. Conclusions: Twenty one percent of this sample of apparently healthy pregnant women had a clinical or subclinical hypothyroidism.

Cáncer papilar de tiroides a la luz de las evidencias actuales / Papillary thyroid cancer: an update

The new screening and diagnostic tools for thyroid cancer lead to a higher prevalence of the disease. This requiresa new approach to the therapy of thyroid cancer, that usually has an indolent and slow evolution. The incidence of microcarcinoma is increasing since the vast majority of thyroid cancers are diagnosed during a screening ultrasonography. In papillary thyroid cancer there is a familial aggregation and close relatives of an index patient have three to six times more risk of having the disease. Exposure to radiation, older age and association with other thyroid diseases are external risk factors for the disease. Thyroid cancer is staged using TNM classification, that allows to establish prognosis. There is still discussion about the best treatment in early stages of the disease. Our working group always recommends total thyroidectomy and radioiodine ablation to obtain a better control and survival and reduce the risk of relapse.

Tiroglobulina y sus limitaciones en el seguimiento del carcinoma diferenciado del tiroides: Report of two cases / Recurrence of differentiated thyroid carcinoma without concomitant elevation of serum thyroglobulin

Thyroid carcinoma is the most prevalent endocrine tumor, and the papillary carcinoma (PC) is the most common histological type. In the follow-up, after thyroidectomy serum thyroglobulin (s-Tg) is used as a marker to evaluate recurrence of thyroid carcinoma. In most cases, this parameter allows an adequate diagnosis, but occasionally s-Tg may miss the detection of a recurrence. We report a 57 year-old female and a 36 year-old male sujected to a total thyroidectomy for a papillary thyroid carcinoma with intermediate and high-risk of recurrence. Both had a cervical recurrence without a concomitant increase in s-Tg levels. In both, Tg staining was positive in the tumor cells. These cases confirm that in these patients, the follow-up must be done with measurement of s-Tg and complementary diagnostic tests.

Características de presentación del microcarcinoma papilar del tiroides. Experiencia retrospectiva de los últimos 12 años / 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.

Microcarcinoma tiroideo de evolución agresiva: Report of one case / Thyroid microcarcinoma with an aggressive evolution

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 6x5x5 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.

Actividad de 11 beta hidroxiesteroide dehidrogenasa tipo 2 en hipertensos chilenos / 11 B-hydroxysteroid dehydrogenase activity in patients with hypertension and low plasma renin activity

Background: Half of hypertensive patients with low plasma renin activity have a primary hyperaldosteronism. Among the remaining half, 11ß-hydroxysteroid dehydrogenase type 2 (11ßHSD2) 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 11ßHSD2 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 (11.1ñ3.3 and 9.2ñ2.8 µg/dl, respectively; p <0.05). No differences were observed in serum cortisone (3.4ñ1.3 and 3.7ñ1.2 µg/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 11ßHSD2 deficiency

Bases clínico moleculares de la hipertensión arterial dependiente de mineralocorticoides / Clinical molecular basis of the mineralocorticoid dependent arterial hypertension

El hiperaldosteronismo primario es una causa potencialmente curable de hipertensión arterial. El uso rutinario de la razón aldosterona/actividad de renina plasmática como test de screenning ha demostrado que existe una alta prevalencia de esta enfermedad, cercana al 10 por ciento de la población de hipertensos. Esta frecuencia es claramente más alta que la clásicamente descrita cuando la hipokalemia es usada como método de screening. Los subtipos más comunes de hiperaldosteronismo primario son el hiperaldosteronismo supresible por glucocorticoides y la hiperplasia adrenal primaria. El diagnóstico de hiperaldosteronismo primario está dirigido en primer lugar a confirmar la autonomía de la secreción de aldosterona del eje renina-angiotensina y posteriormente a diferenciar los tipos subclínicos de la enfermedad. Este artículo es una puesta al día de los nuevos datos acerca de la prevalencia, criterios diagnósticos y describe las características clínicas, bioquímicas y genéticas de los diferentes subtipos de la enfermedad. Además discutimos el diagnóstico diferencial con otros estados de hipermineralocorticoidismo no dependientes de aldosterona como son el déficit de 11ß-hidroxiesteroide deshidrogenasa tipo II, defectos en el canal renal de sodio o las formas hipertensivas de la hiperplasia suprarrenal congénita (11ß-hidroxilasa y 17a-hiroxilasa)

Isquemia miocárdica reversible en el hipotiroidismo: comunicación de un caso / Reversible myocardial ischemia associated to hypothyroidism: report of one case

A silent, reversible myocardial ischemia with normal coronary angiography and reversible with thyroid hormone substitution, has been recently described in hypothyroid patients. We report a 49 years old male with an abnormal exercise electrocardiogram detected in a preventive medical examination. He had laboratory evidence of hypothyroidism and a history of two years of asthenia and progressive coarsening of the voice. The Thallium myocardial perfusion study, showed an alteration of coronary flow during exercise in the septum and lower wall of the left ventricle. Thyroid hormone substitution was started and three months later, a coronary angiography was normal. After six months a repeated Thallium perfusion study and exercise electrocardiogram were informed as normal

Exceso de mineralocorticoides en hipertensos esenciales: enfoque clínico diagnóstico / Evidences for mineralocorticoid excess in essential hypertension: clinic and diagnosis viewpoint

Background: Primary hyperaldosteronism is more frequent among subjects with essential hypertension than previously thought. The prevalence, according to local and international evidence could fluctuate between 9 and 10 percent. Aim: To investigate if subjects with essential hypertension have different aldosterone and renin plasma levels than normotensive subjects. Patients and methods: One hundred twenty five subjects with essential hypertension, not receiving medications for at least two weeks prior to the study and 168 age and sex matched normotensive controls were studied. Blood was drawn between 9 and 10 AM during a sodium free diet to determine plasma aldosterone, plasma renin activity and potassium. Results: Plasma aldosterone was higher in hypertensive subjects than controls (11.6 ñ 7.6 and 9.9 ñ 5.1 ng/dl respectively; p=0.04). Plasma renin activity was lower in hypertensives than controls (1.42 ñ 1.28 and 1.88 ñ 1.39 ng/ml/h respectively; p<0.001). Thus, plasma aldosterone/plasma renin activity ratio was higher in hypertensives (13.8 ñ 13.5 and 8.3 ñ 7.8; p<0.001). A pathological ratio was defined as over 25, corresponding to the mean plus two standard deviations of the control group. Primary hyperaldosteronism was found in 5/125 hypertensives (4 percent) and 1/168 normotensive subject (0.6 percent). None had hypokalemia. Conclusions: Subjects with essential hypertension have higher plasma aldosterone and lower plasma renin activity than normal controls. A plasma aldosterone/plasma renin activity over 25 was defined as abnormal

Recambio óseo en nodrizas adolescentes: evaluación al término de la gestación, lactancia y postdestete / Bone turnover in lactating teenagers: assessment at the end of pregnancy during and after the breast feeding period

Background: There is paucity of information about bone metabolism during pregnancy or breast feeding in teenagers. Aim: To study bone turnover at the end of pregnancy and during breast feeding in teenagers and correlate it with environmental, hormonal or nutritional variables. Subjects and methods: Thirty teenagers during their breast feeding period after a first pregnancy and 30 nulliparous girls matched for age, age of menarche and body mass index were assessed three weeks after delivery (period 1), at six months of breast feeding (period 2) and one year after the lactating period (period 3). Calcium intake and plasma calcium, phosphorus, alkaline phosphatases, parathormone, estradiol and prolactin were measured. Calcium, creatinine and hydroxyproline were also measured in a morning urine sample. Results: Lactating and control girls were aged 16.3ñ0.8 and 16.1ñ0.7 years old respectively. Calcium intake in lactating and control girls was 798ñ421 and 640ñ346 g/day respectively in period 1, 612ñ352 and 592ñ309 mg/day in period 2 and 495ñ180 and 456ñ157 g/day in period 3. During periods 1 and 2, lactating girls had higher alkaline phosphatases (161ñ37 compared to 119ñ28 U/l and 149ñ37 compared to 106ñ23 U/l), parathormone (4.3ñ2.6 compared to 2.8ñ0.8 ng/dl and 3.6ñ1.6 compared to 3.0ñ0.9 ng/dl) and urinary hydroxyproline (95ñ16 compared to 63ñ15 mg/g creatinine and 84ñ19 compared to 59ñ15 mg/g creatinine). No differences were observed in period 3. No correlation between bone turnover variables, body mass index or hormonal parameters, was observed. Conclusions: In teenagers, there is an increase in bone turnover at the end of pregnancy, that persists during the lactating period. These changes are not related to nutritional or hormonal variables

Alta prevalencia de hiperaldosteronismo primario no diagnosticado en hipertensos catalogados como esenciales / High prevalence of undiagnosed primary hyperaldosteronism among patients with essential hypertension

Background: Classically, primary hyperaldosteronism was diagnosed in no more than 1 percent of patients with hypertension, when hypokalemia was used as the screening test. However, numerous patients with primary hyperaldosteronism do not have hypokalemia and the disease remains undiagnosed. Aim: To assess the prevalence of normokalemic primary hyperaldosteronism among patients classified as having essential hypertension. Patients and methods: One hundred hypertensive patients with a blood pressure over 145/95 were studied. Plasma aldosterone and plasma renin activity were measured in all. A primary hyperaldosteronism was diagnosed when high aldosterone levels (over 16 ng/dl) and low plasma renin activity (below 0.5 ng/ml/h) coexisted in two blood tests or the aldosterone/plasma renin activity ratio was over 50. A probable primary hyperaldosteronism was diagnosed when the ratio was between 25 and 50 and these patients were subjected to a Fludrocortisone test to confirm the diagnosis. A dexametasone suppression test was done to discard glucocorticoid remediable aldosteronism. An adrenal TAC scan was done to all patients with primary hyperaldosteronism. Results: A diagnosis of primary hyperaldosteronism was reached in ten patients. Seven had elevated aldosterone and low plasma renin activity. In three the diagnosis was confirmed with the fludrocortisone test. All ten patients had normal serum potassium levels. Dexametasone suppression test was positive in three patients, that normalized their blood pressure levels. Adrenal TAC scans showed an adenoma in one patient and hyperplasia in another. Conclusions: Primary hyperaldosteronism is more frequent than previously thought, it is overlooked when hypokalemia is used as the screening test and it can only be diagnosed measuring plasma aldosterone and renin activity

Hipertiroxinemia con eutiroidismo clínico: análisis a propósito de un caso / Hyperthyroxinemia and clinical euthyroidism: report of one case

The association of hyperthyroxinemia and euthyroidism is frequent and characterized by high plasma thyroxin concentrations, normal TSH values and absence of clinical signs of hyperthyroidism. We report an asymptomatic 28 years old male presenting with a serum total plasma thyroxin of 18.5 µg/dl (N 6.1-12.5), a free thyroxin of 2.9 ng/dl (N 0.8-1.4), a TSH of 3.4 µIU/ml (N 0.5-5), and a triiodothyronine of 128 ng/dl (N 80-180). Laboratory assessment did not find high thyroxin binding globulin, albumin or prealbumin concentrations or antithyroxin antibodies. The thyroxin binding capacity of albumin was elevated to 58.2 µg/dl (N 11.5-34.1). TSH responded normally to TRH stimulus and was suppressed with exogenous triiodothyronine, which caused an hyperthyroid syndrome. We concluded that this patient had a familial dysalbuminemia

Hipertensión arterial tratable con glucocorticoides: comunicación de un caso / Glucocorticoid treatable hypertension: report of one case

Lately, a series of hypertensive syndromes of unknown etiology that respond to new forms of therapy, have been described. One of these is glucocorticoid remediable hypertension, that evolves with suppressed plasma renin activity and normal or high serum aldosterone levels, that lead to an aldosterone/plasma renin activity ratio over 30. We report a 45 years old woman with a severe hypertension, despide the use of antihypertensive medications. She had a plasma renin activity of less than 0.3 ng/ml/h, normal serum aldosterone levels (10 ng/ml) and thus a high aldosterone/plasma renin activity ratio. She had normal serum potassium and sodium levels. Due to the bad results of conventional antihypertensive medications, a treatment with dexamethasone was started normalized blood pressure and allowed to discontinue other antihypertensive medications. This type of hypertension must be sought since non conventional treatments could be used for refractory hypertensive syndromes

Cáncer tiroídeo tipo intermedio folicular-medular; una forma inhabitual, particular y agresiva: comunicación de tres casos / Mixed medullary and follicular carcinoma of the thyroid: report of three cases

Mixed medullary and follicular carcinomas of the thyroid shares secretory and immunohistochemical features of both follicular and parafollicular thyroidal cells. We report three women, aged 34, 63 and 61 old with this type of tumor. Its diagnosis must be bore in mind in patients with thyroidal tumors and a histological appearance of a medullary or undifferentiated carcinomas. An early diagnosis of a mixed medullary and follicular carcinomas of the thyroid is important, considering its special treatment and negative prognosis

Quistes paratiroideos funcionantes y no funcionantes: entidades con origen y clínica diferente en dos casos / Functioning and non functioning parathyroid cysts: report of 2 cases

We report two women presenting with parathyroid cysts. A 20 years old woman presented with goiter and a cystic lesion in the left thyroid lobe was identified on ultrasound examination and CAT scan. The patient had hypercalcemia and elevated PTH levels. The content of the cyst, obtained by needle aspiration, had an extremely high PTH concentration. The patient was operated, removing the cyst and a remaining thymus. Pathological study confirmed the diagnosis of a parathyroid cyst. An 11 years old girl presented with a mass in the left thyroid lobe. An ultrasound examination disclosed the presence of a cystic nodule. The patient was otherwise asymptomatic and laboratory work up was normal. The patient was operated and pathological examination of the surgical piece revealed a parathyroid cyst