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Background: Chronic cocaine users develop multiple potentially lethal ischemic vascular complications associated with accelerated atherosclerosis. Aim: To assess biochemical and lipid profiles among cocaine dependent subjects in recent abstinence. Material and methods: A blood sample to measure blood count, biochemical and lipid profiles was obtained from 78 patients aged 19 to 53 years (78% males) who complied with DSM –IV criteria for cocaine dependency. Laboratory results were compared with a group of normal subjects. Results: All cases had positive urinary cocaine, with a mean consumption lapse of 7.6 years. The frequency of smoking was higher in cases. Dependent males had higher body mass index than controls. Compared to controls, dependent females had significantly higher triglyceride (TG) levels and lower HDL cholesterol. Therefore the relation total/HDL cholesterol was higher (p=0.0365). Dependent males had higher TG levels than their normal counterparts. Dependent subjects consuming cocaine base-paste had higher TG levels. Total proteins, albumin, urea and blood urea nitrogen were lower in dependent subjects. Among males, serum creatinine was lower and blood urea was positively correlated with the daily amount of cocaine use (p=0.03). After a month of strict abstinence, lipid profile was repeated in 27 patients and remained unchanged. Conclusions: Chronic cocaine use was associated with higher TG in both genders and lower HDL cholesterol in women when compared which a group of healthy counterparts.

Coronary angiography is the "gold standard" for the diagnosis of coronary artery disease (CAD). The aim of this work was to compare 201Thallium SPECT with different coronary angiographic cutoff values.Data pertaining to 145 patients were tabulated. All patients underwent stress ECG, 201Thallium SPECT and coronary angiography. To assess the cutoff impact, two criteria for coronary angiography diagnosis were used: a)or = 50% and b)or = 75% stenosis, and applied to data from patients and vessels.On a patient basis, 201Thallium SPECT sensitivity, specificity and accuracy were 87%, 57% and 81% withor = 50% cutoff and 93%, 51% and 79% withor = 75% cutoff, respectively (NS). When performing individual vessel analysis, sensitivity, specificity and accuracy were 59%, 78% and 68% foror = 50% cutoff and 70%, 75% and 74% foror = 75% cutoff, respectively (p0.029 for sensitivity). As expected, the severer the stenosis the higher the detection rate. There were 19 patients who had stenosis between 50% and 74%. Of these, 21% had abnormal stress ECG and 58% abnormal Thallium-201 SPECT.201Thallium SPECT results support the use ofor = 50% stenosis cutoff criteria for CAD diagnosis and evaluation. Combined with coronary angiography, myocardial SPECT offers an excellent management strategy to patients.

Chronic cocaine users develop multiple potentially lethal ischemic vascular complications associated with accelerated atherosclerosis.To assess biochemical and lipid profiles among cocaine dependent subjects in recent abstinence.A blood sample to measure blood count, biochemical and lipid profiles was obtained from 78 patients aged 19 to 53 years (78% males) who complied with DSM-IV criteria for cocaine dependency. Laboratory results were compared with a group of normal subjects.All cases had positive urinary cocaine, with a mean consumption lapse of 7.6 years. The frequency of smoking was higher in cases. Dependent males had higher body mass index than controls. Compared to controls, dependent females had significantly higher triglyceride (TG) levels and lower HDL cholesterol. Therefore the relation total/HDL cholesterol was higher (p = 0.0365). Dependent males had higher TG levels than their normal counterparts. Dependent subjects consuming cocaine base-paste had higher TG levels. Total proteins, albumin, urea and blood urea nitrogen were lower in dependent subjects. Among males, serum creatinine was lower and blood urea was positively correlated with the daily amount of cocaine use (p = 0.03). After a month of strict abstinence, lipid profile was repeated in 27 patients and remained unchanged.Chronic cocaine use was associated with higher TG in both genders and lower HDL cholesterol in women when compared with a group of healthy counterparts.

Objective— Cocaine consumption is a risk factor for vascular ischemic complications. Although endothelial dysfunction and accelerated atherosclerosis have been observed in cocaine consumers, the mechanisms underlying their pathogenesis are not fully understood. This study aimed at identifying the effects of atorvastatin in relation to a proadhesive and prothrombotic phenotype induced by cocaine and plasma from chronic cocaine users on endothelial cells. Approach and Results— Human umbilical vein endothelial cells were exposed to either cocaine or platelet-free plasma (PFP) from chronic cocaine consumers in the presence or absence of 10 μmol/L of atorvastatin. Atorvastatin significantly reduced the enhanced platelet adhesion that was induced by cocaine and PFP from chronic cocaine consumers, as well as the release of the von Willebrand factor. Atorvastatin also avoided striking alterations on cell monolayer structure triggered by both stimuli and enhanced NO reduction because of cocaine stimulation through disrupting interactions between endothelial nitric oxide synthase (eNOS) and caveolin-1, thus increasing eNOS bioavailability. Cocaine-increased tissue factor–dependent procoagulant activity and reactive oxygen species generation were not counteracted by atorvastatin. Although monocyte chemoattractant protein-1 levels were not significantly higher than controls either under cocaine or PFP stimulation, atorvastatin completely avoided monocyte chemoattractant protein-1 release in both conditions. Platelets stimulated with cocaine or PFP did not express P-selectin, glycoprotein IIb/IIIa, or CD40L and failed to adhere to resting human umbilical vein endothelial cell. Conclusions— Cocaine and patient plasma equally induced a proadhesive and prothrombotic phenotype in endothelial cells, except for von Willebrand Factor release, which was only induced by PFP from chronic cocaine consumers. Atorvastatin improved endothelial cell function by reducing cocaine-induced and PFP from chronic cocaine consumer–induced effects on platelet adhesion, cell architecture, and NO production.

The main goal of this work was to know the value of ventricular function in addition to perfusion Tc-99m sestamibi images in the assessment of coronary artery disease (CAD) when using dipyridamole (DIP) associated to isometric exercise. We analyzed 52 patients with suspected CAD; 40 of them had coronary lesionsor = 50% and 12 patients without CAD, conforming study and control groups, respectively. Twenty-eight patients had prior myocardial infarction. A two-day sestamibi protocol was employed with i.v. DIP-handgrip and rest injections, acquiring ECG-gated first pass and planar perfusion images. Sensitivity for perfusion images was 85% and specificity was 91.7%. There was no change between rest and DIP ejection fraction (EF) in controls. CAD patients presented a significant EF decrease with DIP (p: 0.0015). Patients with ischemia in perfusion images had larger EF decrease (p: 0.0001). For the analysis, an EF dropor = 5% and any wall motion abnormality (WMA) were considered as having an abnormal response to DIP. CAD sensitivity improved significantly to 92.5% when adding EF drop and to 90% when adding WMA parameters, but specificity decreased to 75% with EF drop, and to 58.3% with WMA. In conclusion, first pass parameters from DIP-isometric exercise in addition to perfusion images are not a significant help in the assessment of CAD.

Bariatric surgery has important metabolic complications such as bone mass loss.To assess bone mineral density (BMD) after Roux-en-Y gastric by-pass (RYGB) in patients under standard calcium and vitamin D supplementation.In patients with morbid obesity submitted to RYGB, 76 women and 22 men of diverse age, all with standard nutritional instruction including vitamin D and calcium, we measured BMD with a dual X-ray densitometer. They had lumbar spine and hips measurement 2-3 years post-surgery. Twenty females were followed up with BMD until of a mean of 54 months. Using World Health Organization (WHO) criteria's, values were compared with young controls and same age and sex population, evaluating osteopenia and osteoporosis.Inverse correlation was observed between BMD and age; positive between BMD and body mass index as well as with preoperative weight excess. In women younger than 45 years, we observed a diminished BMD in 26.8% of them, with no cases of osteoporosis. In older females, BMD was decreased in 65.7% (p = 0.0011); corresponding to 45.7% of osteopenia and 20% osteoporosis, more frequent in lumbar spine. In the female's subgroup followed longer, BMD diminished progressively mainly in left hip. In men, there was 36% of osteopenia and 14% of osteoporosis.Patients from both genders and diverse ages after BPYR presented osteopenia and osteoporosis, despite early supplement prescription of calcium and vitamin D. We consider important to perform serial BMD measurements and also to individualize therapy with risk factors control.Introducción: La cirugía bariátrica tiene complicaciones metabólicas importantes como la pérdida de masa ósea. Objetivo: Evaluar la densidad mineral ósea (DMO) posterior a by-pass gástrico en Y de Roux (BPYR) en pacientes con indicación de suplemento estándar de calcio y vitamina D. Método: En pacientes con BPYR por obesidad mórbida, 76 mujeres y 22 hombres de diversa edad, con instrucción nutricional, suplemento de calcio y vitamina D, se midió la DMO en columna lumbar y caderas con densitómetro radiológico de doble haz 2 a 3 años post-cirugía. Veinte mujeres fueron seguidas con DMO hasta 54 meses en promedio. Según criterios de Organización Mundial de la Salud (OMS), se comparó con población control joven y de su edad según sexo, evaluando osteopenia y osteoporosis. Resultados: Hubo correlación negativa de DMO con edad; positiva de DMO con índice de masa corporal y con exceso de peso preoperatorio. En mujeres menores de 45 años, se observó disminución de DMO en 26,8%, sin casos de osteoporosis y en 65,7% en las mayores de 45 años (p = 0,0011), correspondiendo a 45,7% de osteopenia y 20% de osteoporosis, predominantemente en columna lumbar. El subgrupo de mujeres con mayor seguimiento, presentó disminución progresiva de DMO, especialmente en cadera izquierda. En hombres se observó 36% de osteopenia y 14% de osteoporosis. Conclusión: Pacientes de ambos sexos y diversa edad, despues de un BPYR, presentaron osteopenia y osteoporosis, a pesar de suplemento precoz de calcio y vitamina D. Consideramos importante medir DMO seriada, individualizando terapias y controlando factores de riesgo.

Cocaine consumption is associated with increased risk of cardio- and cerebrovascular diseases, which are the consequence of endothelial dysfunction (ED). We recently showed that cocaine use is related to increased ED markers including circulating endothelial cells, although the mechanisms governing ED in cocaine users are still being researched. Since the RhoA/Rho kinase (ROCK) pathway is involved in the pathogenesis of ED, our Aim was to study in vitro and ex vivo RhoA/Rho kinase activation and ED markers in relation to cocaine consumption. Method Plasma samples from active cocaine consumers who met DSM-IV criteria and age and gender-matched controls were tested. ROCK activity, von Willebrand factor (vWf), Metalloproteases (MMP) and platelet adhesion were evaluated in HUVEC supplemented with cocaine (10μM), 10% plasma from cocaine users (CP), normal plasma (NP) or vehicle, in the presence or absence of Y-27632 (10 μM) and atorvastatin (ATS:10μM). Results CP induced higher ROCK (p: 0.039) and MMP 2 activity (pEx vivo studies showed significantly higher ROCK (p 0.015), MMP-2 (p Conclusions Cocaine and cocaine consumer plasma increased ROCK activity in HUVEC, resembling the ex vivo findings. Only CP induced higher MMP activity and release of vWf resembling the findings in patients. The significant reduction of most of the in vitro effects by ATS and Y-27632 may provide a novel and potential therapeutic tool for the protection of the endothelium from deleterious stimuli such as cocaine consumption.

The main goal of this study was to evaluate whether the addition of ECG gating to technetium-99m sestamibi single-photon emission tomographic (SPET) perfusion imaging assists the prediction of recovery of regional wall motion abnormalities after revascularization. Thirty-six patients with coronary artery disease were included in the study. All had wall motion abnormalities, and 31 (86%) had a clinical history of myocardial infarction. Coronary artery bypass surgery was performed in 18 patients and angioplasty in the remainder. All underwent ECG-gated and non-gated SPET at rest and after intravenous dipyridamole. Two-dimensional echocardiography was performed at a mean of 27 days before revascularization and at a mean of 69 days following revascularization to assess segmental wall motion changes. Perfusion prior to revascularization was analysed qualitatively and quantitatively on gated and non-gated SPET, and the results compared with those of echocardiography. Bullseye parameters were obtained from a normal database, generated from data in 40 normal volunteers, using dipyridamole ECG-gated and non-gated sestamibi SPET. There was good concordance between gated and non-gated qualitative analysis (79% with kappa=0.65) for normal, viable or necrotic segments. Gated SPET predicted functional recovery in 27 of 35 (77%) segments showing echocardiographic improvement while non-gated SPET did so in 30 of 39 (77%) such segments. Gated SPET predicted no functional recovery in 20 of 45 (44%) segments that did not show improved wall motion after revascularization, while with non-gated SPET the figure was 18 of 51 (35%). The positive predictive values of gated and non-gated SPET with regard to the recovery of wall motion following revascularization were 52% and 48%, while the negative predictive values were 71% and 67%, respectively. 99mTc-sestamibi had a low predictive value for recovery of function if visual assessment was used in the analysis of SPET data. Quantitative bullseye sestamibi parameters (defect extension and severity, reversibility and percentage change in extension), from gated or non-gated studies, appear best to distinguish which segments will display improved motility on the echocardiogram after revascularization. The addition of ECG gating does not significantly increase the predictive value of SPET imaging with regard to recovery of function.

Antecedentes: El rendimiento del estudio de perfusión miocárdica en pacientes con Diabetes Mellitus (DM) y sin síntomas coronarios es controvertido. Objetivo: Efectuar un seguimiento a 5 años para eventos cardíacos mayores en DM asintomáticos estudiados con SPECT miocárdico en esfuerzo. Método: Se estudiaron 40 pacientes asintomáticos coronarios, con DM conocida por >5 años, >45 años de edad, con >2 factores de riesgo cardiovascular (FRCV) y electrocardiograma basal normal o con alteraciones inespecíficas. Todos efectuaron una prueba de esfuerzo (PE) adecuada y se estudiaron con Sestamibi-Tc99m repetido en 32 casos al 3° año. Además, se evaluó a 36 controles no diabéticos con >2 FRCV. El seguimiento fue de 64±11 meses. Resultados: En el grupo DM, 48% tenía Hba1c>7.5%; en ellos el SPECT mostró isquemia silente (IS) en 30% y la PE en 18% del total. No hubo variaciones significativas en SPECT al 3° año. Hubo una muerte no cardíaca en el 2° año; en el 4° año, se produjo una muerte por infarto agudo de miocardio, con mínima isquemia septal y otra asociada a miocardiopatía e insuficiencia cardíaca, con defecto de predominio fijo, ambos con PE negativa. En el grupo control, el 11% tuvo SPECT anormal y 8% PE positiva; hubo una muerte no cardíaca. El Odds Ratio para isquemia fue 3.42 [IC=0.99-11.85] entre DM vs controles y el Hazard Ratio para eventos cardíacos 6.75 [IC=0.40-108.2]. Conclusiones: En DM asintomáticos coronarios el riesgo de IS en SPECT fue mayor que en controles sin DM y con FRCV. Los eventos cardiacos mayores fueron más frecuentes, aunque no significativamente, en DM que en controles. Ello deberá reevaluarse conocidos los resultados del estudio multicéntrico.

Background: The usefulness of positron emission tomography (PET) with fluorine-deoxyglucose (FDG) in sarcomas and non-sarcoma non-epithelial (NSNE) tumors is not clearly defined. Aim: To report a Chilean experience with NSNE tumors evaluated using PET with FDG. Material and Methods: Retrospective review of the database of a PET laboratory. Demographic data, indications and metabolic findings were compared with conventional imaging in 88 adults and children with diverse bone and soft tissue sarcomas as well as 24 gastrointestinal stromal tumors (GIST), 6 pleural malignant mesotheliomas in adults, and 9 medulloblastomas in children. Results: FDG showed good concordance with conventional imaging in NSNE tumors. It was helpful for staging, restaging, follow-up after treatment and for the detection of new not previously suspected lesions. Conclusions: PET with FDG could have a prognostic role and help in patient management, mainly in musculos-keletal and high grade or less differentiated sarcomas. In GIST, it was a good tool for immunotherapy control.

A. Veronica Araya1, Teresa Massardo2, Jenny Fiedler3, Luis Risco4, Juan C. Quintana5 and Claudio Liberman1 1Endocrinology Section, Clinical Hospital of the University of Chile 2Nuclear Medicine Section, Clinical Hospital of the University of Chile 3Faculty of Chemical and Pharmaceutical Sciences, University of Chile 4Psychiatric Clinic of the Clinical Hospital of the University of Chile 5Department of Radiology, School of Medicine, Pontificia Universidad Catolica de Chile Chile

The usefulness of positron emission tomography (PET) with fluorine-deoxyglucose (FDG) in sarcomas and non-sarcoma non-epithelial (NSNE) tumors is not clearly defined.To report a Chilean experience with NSNE tumors evaluated using PET with FDG.Retrospective review of the database of a PET laboratory. Demographic data, indications and metabolic findings were compared with conventional imaging in 88 adults and children with diverse bone and soft tissue sarcomas as well as 24 gastrointestinal stromal tumors (GIST), 6 pleural malignant mesotheliomas in adults, and 9 medulloblastomas in children.FDG showed good concordance with conventional imaging in NSNE tumors. It was helpful for staging, restaging, follow-up after treatment and for the detection of new not previously suspected lesions.PET with FDG could have a prognostic role and help in patient management, mainly in musculoskeletal and high grade or less differentiated sarcomas. In GIST, it was a good tool for immunotherapy control.

Cocaine abuse is associated with an increased risk of cardiac and cerebrovascular events, such as myocardial infarction, sudden cardiac death, and ischemic stroke. The underlying mechanisms leading to these complications are not fully understood although intravascular thrombus formation and accelerated atherosclerosis are prominent findings. We report a 39-year-old male addicted to cocaine, who presented with three consecutive ischemic events characterized by an acute myocardial infarction and two ischemic strokes complicated by cardiac failure and severe neurological sequelae. The pathophysiology of cocaine-induce vascular damage and the management of the ischemic complications are discussed.

Tako-Tsubo syndrome resembles an acute myocardial infarction in symptoms, laboratory parameters and electrocardiographic changes. However, angiography does not show evidence of coronary occlusion, and typically an apical ballooning of the ventricle in systole is observed. We report a 78-year-old woman with no coronary risks factors, admitted to the emergency room due to acute chestpain and an electrocardiogram compatible with an acute coronary syndrome with ST elevation. Serum troponin and creatin-kinase (MB fraction) were elevated. An emergency coronary angiography did not show a coronary occlusion. Due to the apical ballooning observed in the left ventriculography, a probable diagnosis of Tako-Tsubo was proposed. The patient had a favorable evolution. A treadmill test, echocardiogram and myocardial perfusión SPECT, performed one month later, disclosed no abnormalities.

Cocaine abuse increases the risk of cardiac and cerebrovascular events, such as myocardial infarction and ischemic stroke. The underlying mechanisms leading to these complications are not fully understood although intravascular thrombus formation has been observed. The aim of this study was to investigate the existence of platelet activation and the effect of short-term abstinence in chronic cocaine consumers. We studied 23 cocaine dependent individuals (aged 20-54 years) who met DSM-IV criteria for cocaine dependence and 20 controls. Samples were obtained at baseline, within 72 h of last drug exposure and after 4 weeks of controlled abstinence. Monocyte-platelet aggregates (MPA) were measured by flow cytometry. Plasma levels of soluble CD40L (sCD40L), Neutrophil-Activating Peptide-2 (NAP-2) and regulated on activation normal T cells expressed and secreted (RANTES) were determined by ELISA. Levels of MPA, sCD40L, NAP-2 and RANTES were significantly higher (all p 0.05) in cocaine addicts compared to controls at baseline. All the parameters returned to values similar to the control group after 4-weeks' abstinence. Levels of sCD40L and RANTES were associated with an index of intensity of drug consumption (p 0.02). Our results demonstrate that cocaine use induces platelet activation which is a prominent finding after recent consumption. The persistence over time of this condition may contribute not only to acute thrombotic complications but also to the development of early-onset atherosclerotic process observed in cocaine abusers.

Tako-Tsubo syndrome resembles an acute myocardial infarction in symptoms, laboratory parameters and electrocardiographic changes. However, angiography does not show evidence of coronary occlusion, and typically an apical ballooning of the ventricle in systole is observed. We report a 78-year-old woman with no coronary risks factors, admitted to the emergency room due to acute chestpain and an electrocardiogram compatible with an acute coronary syndrome with ST elevation. Serum troponin and creatin-kinase (MB fraction) were elevated. An emergency coronary angiography did not show a coronary occlusion. Due to the apical ballooning observed in the left ventriculography, a probable diagnosis of Tako-Tsubo was proposed. The patient had a favorable evolution. A treadmill test, echocardiogram and myocardial perfusion SPECT, performed one month later, disclosed no abnormalities.

Resumen: Se revisan los protocolos de cardiologia nuclear actuales, con enfasis en los estudios tomograficos de foton unico (“SPECT”) de perfusion miocardica principalmente en evaluacion de enfermedad corona-ria (EC). Las indicaciones y protocolos mas utilizados son detallados, asi como la actualizacion bibliografica pertinente, tanto al uso clinico como al control de ca-lidad e interpretacion de los estudios. Palabras clave: SPECT, perfusion miocardica, enfermedad coronaria. Articulo de revision Departamento de Imagenes Cardiovasculares No Invasivas.Sociedad Chilena de Cardiologia y Cirugia Cardiovascular. *Becario Programa de Medicina Nuclear, Hospital Clinico Universidad de Chile Correspondencia: Teresa Massardo M.D.Seccion Medicina Nuclear, Hospital Clinico Universidad de ChileSantos Dumont 999-1E, Independencia, Santiago, Chile.Zip Code: 6531063Fono Fax (562) 7770569 E-mail: tmassardo@redclinicauchile.cl Introduccion : Se revisan los protocolos de cardiologia nuclear, que han sido ya publicados en esta revista en los anos 1996 y 2004, con enfasis en los estudios tomograficos de fo-ton unico SPECT de perfusion miocardica en evaluacion de enfermedad coronaria (EC)

Anti-thyroid peroxidase antibodies have a pathogenic role in Hashimoto thyroiditis. Between 10 and 19% of individuals without thyroid disease, have positive titers of these antibodies.To study the frequency of positive titers of anti-thyroid peroxidase antibodies in healthy individuals.A blood sample, to measure anti-thyroid peroxidase antibodies and thyroid stimulating hormone (TSH) by chemoluminiscense assay, was obtained from 67women and 62 men aged 45 +/- 14years, without a personal or familiar history of thyroid diseases and normal thyroid palpation. The cutoff point of the manufacturer to consider positive a titer of anti-thyroid peroxidase antibodies was set at 35 IU/ml.Twenty-eight women and 28 men had positive antibody titers (43% of the sample). Subjects in the upper tercile of anti-thyroid peroxidase antibody titers had a higher TSH than those in the second tercile, although within normal limits (1.73 +/- 0.74 and 1.37 +/- 0.59 mlU/L, respectively p = 0.02) CONCLUSIONS: Forty three percent of the studied subjects without personal or familial history of thyroid diseases had positive titers of anti-thyroid peroxidase antibodies. Further prospective studies should evaluate whether this observation discloses an increase in thyroid autoimmune disease in a population with increased iodine intake.

Objective Extracardiac activity (ECA) may affect interpretation of gated SPECT myocardial perfusion studies (MPSs). To solve this problem, available softwares include myocardial edge delimitation. Purpose To evaluate the influence of ECA in automatic myocardial edge detection under normal conditions and with abnormal perfusion and also evaluate the reproducibility of semi-automatic processing. Methods A total of 100 MPSs, 50 with ECA, were analyzed. Each subgroup included 25 cases with perfusion abnormalities. The cases were processed automatically and by 4 independent operators with different levels of experience. Commercial QGS and QPS softwares were used with tools to mask and relocate the left ventricle area. Functional parameters (final diastolic and systolic volumes and ejection fraction) and perfusion parameters such as the reversibility perfusion score and rest perfusion defect extension were analyzed. The data were compared with Pearson's correlation and Student's test. Results Interobserver correlation significantly worsened with the presence of ECA and was moderately affected by perfusion abnormalities. More experienced observers presented better correlation. Reproducibility was greater for the functional perfusion parameters, independently of the observer's experience. Conclusions ECA significantly affects automatic edging delimitation, affecting the MPS values. Interobserver reproducibility with manual processing was more altered regarding funtional parameters than in the perfusion scores. Perfusion abnormalities did not interfere with software reproducibility, and when present, better correlation was found. If ECA is not present, manual intervention should be avoided.

Background: Anti-thyroid peroxidase antibodies have a pathogenic role in Hashimoto thyroiditis. Between 10 and 19% of individuals without thyroid disease, have positive titers of these antibodies. Aim: To study the frequency of positive titers of anti-thyroid peroxidase antibodies in healthy individuals. Material and Methods: A blood sample, to measure anti-thyroid peroxidase antibodies and thyroid stimulating hormone (TSH) by chemoluminiscense assay, was obtained from 67women and 62 men aged 45 ± 14years, without a personal or familiar history of thyroid diseases and normal thyroid palpation. The cutoff point of the manufacturer to consider positive a titer of anti-thyroid peroxidase antibodies was set at 35 IU/ml. Results: Twenty-eight women and 28 men had positive antibody titers (43% of the sample). Subjects in the upper tercile of anti-thyroid peroxidase antibody titers had a higher TSH than those in the second tercile, although within normal limits (1.73 ± 0.74 and 1.37 ± 0.59 mlU/L, respectively p = 0.02) Conclusions: Forty three percent of the studied subjects without personal or familial history of thyroid diseases had positive titers of anti-thyroid peroxidase antibodies. Further prospective studies should evaluate whether this observation discloses an increase in thyroid autoimmune disease in a population with increased iodine intake.

Radiolabeled iodine uptake is a useful tool in the study of thyroid diseases.To obtain normal values for 131 Iodine thyroid uptake in healthy volunteers.A total of 105 subjects were included (52 males and 53 females), with a mean age of 45 years (range: 20 to 68, evenly distributed in decades). A questionnaire was applied and a clinical examination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral 131I dose was 5-10 microCi, and a Thyrad equipment was used for measurements at 2 and 24 h.Mean global iodine uptake was 5.5%+/-1.8% (range: 2.3-12.0) at 2 h and 16.2+/-4.8% (range: 6.5-30.1) at 24 h. The values at 2 h among women and men were 6.0+/-1.8 and 4.9+/-1.6%, respectively, (p0.02). At 24 h, the figures were 17.3+/-4.5 and 15.0+/-4.9%, respectively (p=0.01). Compared to their younger counterparts, radioactive iodine uptake was lower among volunteers older than 40 years, at 2 h (5.0+/-1.7 and 6.0+/-1.8, respectively, p0.02) and at 24 h (14.9+/-4.4 and 17.6+/-4.9%, respectively, p0.01).Normal thyroid uptake values in adults are influenced by gender and age. Normal thyroid iodine uptake values are slightly higher in females. Iodine thyroid uptake values decrease slightly in subjects aged more than 40 years.

Double-phase scintigraphy with Tc-99m sestamibi is a good method to detect hyperfunctioning parathyroid glands. This study tried to determine the best time for delayed images: 2 or 4 hours.Fifty-six patients were studied, and 35 of them had primary hyperparathyroidism (mean age, 53 +/- 13 years; 54% were women). Cervical ultrasonography was performed on 29 of 56 (52%) patients and surgery in 16 of 56 (29%) patients. The dose was 740 MBq (20 mCi) given intravenously, and the acquisition was performed at 10 minutes, 2 h, and 4 h using anterior views, including the mediastinum. Studies that had positive results were analyzed blindly by two independent observers, who selected the best definition for abnormal activity.Nineteen of 56 (34%) studies were negative and 37 of 56 (66%) were positive, 25 of them with one focus and 12 with two or more parathyroid foci. Analysis revealed 76% agreement between the observers (the rest was classified by consensus). In 70% of the cases, the best delayed image was obtained at 2 hours, in 16% at 4 hours (P0.00001), and in 14% both images were similar. In those cases with better images at 4 hours, the 2-hour images also showed the lesions. In two patients, lesions were seen only at 2 hours. These results could be explained by tracer decay, washout of parathyroid activity, or both.The best protocol should include the early 10-minute image and the 2-hour delayed view. Further controls do not appear necessary. This may be important for patient throughput.

Background: Radiolabeled iodine uptake is a useful tool in the study of thyroid diseases. Aim: To obtain normal values for 131 Iodine thyroid uptake in healthy volunteers. Material and methods: A total of 105 subjects were included (52 males and 53 females), with a mean age of 45 years (range: 20 to 68, evenly distributed in decades). A questionnaire was applied and a clinical examination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral 131I dose was 5-10 fiCi, and a Thyrad equipment was used for measurements at 2 and 24 h. Results: Mean global iodine uptake was 5.5%±1.8% (range: 2.3-12.0) at 2 h and 16.2±4.8% (range: 6.5-30.1) at 24 h. The values at 2 h among women and men were 6.0±1.8 and 4.9±1.6%, respectively, (p

FDG PET is a technique that evaluates glucose cell metabolism. Its main utility is in oncology. PET scan is useful distinguishing benign from malignant neoplasms, selecting the site for biopsy, malignancy staging, response to therapy and distinguishing scar from residual neoplasm in children who complete therapy. Indications for PET in children are lymphoma, central nervous system tumors, soft tissue sarcoma, osteosarcoma, Ewing sarcoma, neuroblastoma and nephroblastoma. Other less common tumors are: plexiform neurofibroma, hepatoblastoma, Wilms tumor and thyroid cancer. There are few reports in children due to less cases reported and low cancer incidence. It is important to consider normal FDG distribution and children variations to optimize interpretation. The main goal of this article is to review FDG PET indications, as well as present our initial casuistry in pediatric population.

Clinical oncology is the main application of 18F-deoxyglucose (FDG) positron emission tomography (PET).To evaluate the first 1,000 patients studied with FDG PET in Chile.Retrospective analysis of 1,000 patients (aged between 1 and 94 years, 550 females) studied with FDG PET, since 2003. All studies were performed in a high resolution Siemens Ecat-Exact HR (+). All reports were based on the visual analysis of three plane and three-dimensional images.Ninety seven percent of exams were done for oncological indications, mainly lung lesions, lymphoma, colorectal and gastroesophageal, cancer and breast tumors. Only 1% of patients had brain tumors. Non tumor neurological indications corresponded to 1.7%. Cardiac studies were only 0.3% and inflammatory process corresponded to 1%. The 5.6% corresponded to pediatric population. Six percent of patients were aged less than 18 years and in 50% of them, the indication was oncological, mainly lymphomas, brain tumors, endocrine cancers and sarcomas. The remaining 50% had a neurological indications, mainly for refractory epilepsy.PET FDG imaging was effective in the management of diverse diseases of children and adults.

Se presenta el caso de un hombre de 57 anos que presenta un cuadro degenerativo con afasia fluente y moderadas alteraciones de conducta, sin defecto semantico significativo, agnosia visual ni agrafia lexical y su estudio imagenologico cerebral. Se discuten los conceptos de afasia progresiva fluente y demencia semantica, concluyendo que la primera puede evolucionar hacia esta ultima. Nuestro caso se encontraria en esta situacion. Se senala que la patologia de las afasias progresivas es variable, siendo lo mas frecuente una degeneracion frontotemporal (con o sin inclusiones de proteina tau); con menor frecuencia corresponde a una enfermedad de Alzheimer o una degeneracion corticobasal

Background: Clinical oncology is the main application of 18F-deoxyglucose (FDG) positron emission tomography (PET). Aim: To evaluate the first 1,000 patients studied with FDG PET in Chile. Material and methods: Retrospective analysis of 1,000 patients (aged between 1 and 94 years, 550 females) studied with FDG PET, since 2003. All studies were performed in a high resolution Siemens Ecat-Exact HR (+). All reports were based on the visual analysis of three plane and three-dimensional images. Results: Ninety seven percent of exams were done for oncological indications, mainly lung lesions, lymphoma, colorectal and gastroesophageal, cancer and breast tumors. Only 1% of patients had brain tumors. Non tumor neurological indications corresponded to 1.7%. Cardiac studies were only 0.3% and inflammatory process corresponded to 1%. The 5.6% corresponded to pediatric population. Six percent of patients were aged less than 18 years and in 50% of them, the indication was oncological, mainly lymphomas, brain tumors, endocrine cancers and sarcomas. The remaining 50% had a neurological indications, mainly for refractory epilepsy. Conclusions: PET FDG imaging was effective in the management of diverse diseases of children and adults

Accurate assessment of ventricular function is required to optimize therapeutic management of cardiac diseases. The aim of this study was to correlate planar equilibrium multigated acquisition (MUGA) with tomographic ventriculography (SPECT) in patients with diverse volumes and wall motion abnormalities.Eighty-three studies in 80 patients (56+/-14 years; 56% women) were classified according to ventricular dilation, wall motion abnormalities and systolic dysfunction. Left and right ventricular ejection fraction (LVEF and RVEF) and end-diastolic and end-systolic left ventricular volumes (EDV and ESV) were obtained using a commercial QBS program for SPECT. On planar acquisition, LVEF and RVEF were obtained using standard techniques and volumes were determined using the count-based method, without blood sampling.A. Total group: With the planar method, LVEF was 44+/-17%, RVEF 42+/-13%, left EDV 147+/-97 ml (range 31-487 ml) and left ESV 93+/-85 ml (range 15-423 ml); with SPECT the corresponding values were 40+/-20%, 49+/-16%,131+/-95 ml and 91+/-89 ml, respectively (p=NS for all but RVEF). Linear correlation was 0.845 for LVEF, 0.688 for RVEF, 0.927 for left EDV and 0.94 for left ESV, with good intra-class correlation. B. Subgroups: Global and intra-class correlations between planar imaging and SPECT were high for volumes, RVEF and LVEF in all subgroups, except in patients with normal wall motion and function, who showed smaller volumes with SPECT. The group with diffuse wall motion abnormalities had a lower EDV on SPECT. In the abnormal left ventricle, RVEF was higher with SPECT.Good correlation and agreement exist between SPECT and planar MUGA with respect to LVEF and left ventricular volumes. SPECT is useful in patients with functional abnormalities, but less reliable in those with normal small cavities. A combined technique is still necessary, and RVEF should be interpreted cautiously.

Positron emission tomography (PET) with fluorine-18 labeled deoxyglucose (FDG) is useful in the management of lymphomas. In this review, some general concepts of this metabolic test are defined. It has an excellent diagnostic yield in Hodgkin disease as well as in most non Hodgkin lymphomas. Staging, restaging residual mass evaluation and the control of therapy are the main indications for FDG-PET. Images with FDG have a high diagnostic and prognostic value, that is superior to anatomical images and conventional staging techniques. They are also helpful for the assessment of tumor activity in abnormal lymph nodes or large masses that have been treated and reduce their size slowly or show an incomplete resolution. Currently, the resolution of dedicated PET equipments is 6 mm and bigger lesions can easily be detected. The main differences and advantages of FDG versus gallium-67 in lymphoma are also discussed, as well as the initial local experience with the technique in lymphoma patients.

Positron emission tomography (PET) with fluorine-18 labeleddeoxyglucose (FDG) is useful in the management of lymphomas. In this review, some generalconcepts of this metabolic test are defined. It has an excellent diagnostic yield in Hodgkin disease aswell as in most non Hodgkin lymphomas. Staging, restaging residual mass evaluation and thecontrol of therapy are the main indications for FDG-PET. Images with FDG have a high diagnosticand prognostic value, that is superior to anatomical images and conventional staging techniques.They are also helpful for the assessment of tumor activity in abnormal lymph nodes or large massesthat have been treated and reduce their size slowly or show an incomplete resolution. Currently, theresolution of dedicated PET equipments is 6 mm and bigger lesions can easily be detected. The maindifferences and advantages of FDG versus gallium-67 in lymphoma are also discussed, as well as theinitial local experience with the technique in lymphoma patients (Rev Med Chile 2006; 134: 910-9).(

Está establecida en la literatura la utilidad de la tomografía por emisión de positrones (PET) con 18F-flúordeoxiglucosa (FDG) en la etapificación, reetapificación y seguimiento del melanoma maligno. Objetivo: Evaluar los resultados del PET FDG en melanoma maligno en nuestro centro. Material y Método: Entre febrero 2003 y julio 2004, se estudiaron 33 pacientes (edad 49±14 años, 52% sexo masculino) referidos para etapificación y reetapificación de melanoma maligno. El examen fue realizado en equipo de alta resolución Siemens Ecat Exact HR+ con dosis de 13±3 mCi de FDG y glicemias en ayunas preinyección de 96±16 mg/dL. Se adquirieron imágenes de cuerpo entero, incluyendo cabeza y extremidades inferiores. El informe se basó en el análisis visual e índice cuantitativo de captación (SUV). Se comparó con otros estudios de imágenes e histología cuando estaban disponibles y se realizó seguimiento clínico. Resultados: Nueve pacientes fueron derivados para etapificación y 24 para reetapificación. En 29 casos, la localización inicial del primario era conocida y en 4 la enfermedad se diagnosticó por la presencia de metástasis ganglionares. Respecto de la localización tumoral, 6 fueron en cabeza y cuello (2 metástasis ganglionares), 5 en coroides, 5 en tronco, 5 en extremidades superiores, 11 en extremidades inferiores y 1 en mucosa (rectal). En 13 pacientes, el PET fue positivo para presencia de actividad tumoral hipermetabólica, 7 en ubicación próxima al primario y 6 alejados de éste, correspondiendo uno de estos últimos a un segundo primario (carcinoma rectal confirmado con histología). De este grupo, en 11 pacientes se confirmó tumor: en 7 hubo confirmación histológica postcirugía y en los restantes, hubo concordancia con imágenes anatómicas y clínica (1 paciente falleció); además, el PET demostró lesiones no sospechadas por otros estudios, las que no han sido confirmadas con histología. Dos fueron falsos positivos, uno por hematoma y otro por cambios ganglionares inflamatorios demostrados por cirugía. En 16 casos, el PET fue negativo para compromiso neoplásico, comprobándose en el seguimiento clínico de los pacientes. En 4 casos, el PET fue no concluyente para tumor, los que presentan seguimiento clínico negativo hasta la fecha. En los casos referidos por metástasis ganglionares, no se logró encontrar el tumor primario. Conclusión: El PET FDG es un examen útil en la etapificación y reetapificación de los pacientes con melanoma maligno, ya que permite orientar el manejo, disminuyendo morbimortalidad al paciente al evitar cirugías o tratamientos innecesarios cuando está diseminado, con un costo-beneficio importante Background: The usefulness of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) for the staging and follow up of malignant melanoma, is well established. Aim: To assess the results of PET FDG in patients with malignant melanoma. Patients and Methods: Thirty three patients with malignant melanoma (aged 49 ± 14 years, 17 males), referred for staging and restaging, were studied. The tomography was performed using a Siemens Ecat Exat high resolution equipment. The dose of FDG was 13 ± 3 mCi and the blood glucose levels prior to injection were 96 ± 16 mg/dl. Whole body images, including the head and legs were acquired. The report was based on the visual analysis and standardized uptake value (SUV). Results: Nine patients were referred for staging and 24 for restaging. The location of the primary tumor was known in 29 cases and in four, the disease was diagnosed due to the presence of lymph node metastases. The tumor was located in the head and neck in six patients (including two lymph node metastases), in the choroid in five, in the trunk in five, in the superior limbs in five, in the inferior limbs in 11 and in the rectal mucosa in one. In 13 patients, PET was positive for the presence of hypermetabolic tumor activity. In seven, the location was near the primary tumor and in six, it was distant. In seven patients the presence of tumor was confirmed by surgery and in four, there was concordance between the anatomical imaging and clinical outcome. Two false positive images were detected, one hematoma and one due to the presence of lymph node inflammation. In 16 cases, PET was negative and in four it was not conclusive, all these patients do not have evidence of tumor in the clinical follow up. The primary location of the tumor was not identified in patients referred for lymph node metastases. Conclusions: FDG PET is useful for the staging and re staging of patients with malignant melanoma

Introducción: El diagnóstico y etapificación de pacientes portadores de lesiones pulmonares con PET-FDG permite optimizar el manejo y seleccionar la terapia más adecuada para cada uno. Objetivo: Analizar nuestra experiencia preliminar con PET-FDG en la caracterización metabólica de nódulos o masas pulmonares, correlacionándolo con histología cuando estaba disponible y evaluando el impacto en la conducta terapéutica. Material y Método: Se analizaron 58 pacientes referidos para evaluación de nódulo o masa pulmonar (62±7 años de edad; 48% sexo masculino; 40% fumadores). Los PET se realizaron en ayunas, utilizando 13 mCi de FDG-F18, con glicemia preinyección de 101± 5 mg/dl. Se adquirieron imágenes de cuerpo entero con análisis visual de cortes coronales, sagitales y transaxiales e imágenes 3D, así como análisis cuantitativo del índice de captación estandarizada SUV. Los estudios se compararon con histología y seguimiento clínico. Resultados: En 22 pacientes (38%), las lesiones pulmonares fueron hipermetabólicas y en 64%, no hubo evidencias de actividad tumoral. En 24% de los pacientes, se encontraron además lesiones extrapulmonares no sospechadas por otras técnicas de imágenes. El rango de tamaño de los nódulos/masas pulmonares era de 0,5 a 7 cm; en el grupo de PET positivo, el tamaño era mayor a 0,8 cm. Se obtuvo histología en 16/58: en 12 de ellos, se confirmó la presencia de neoplasia (75%), correspondiendo la mayoría a adenocarcinoma. Dos pacientes fueron falsos positivos, demostrándose en uno, un schwanoma abscedado y en el otro, un hamartoma. En 2 pacientes con nódulos sin actividad hipermetabólica al PET (estudio normal), sometidos a cirugía por las características del nódulo al TC, se corroboraron lesiones benignas. En los restantes pacientes con lesiones negativas, el seguimiento clínico no ha demostrado eventos hasta la fecha. Un paciente referido por nódulo pulmonar no fue incluido en el análisis debido a que en el PET presentaba múltiples lesiones hipermetabólicas con patrón sugerente de sarcoidosis, lo que fue confirmado con histología en 5 localizaciones. Conclusión: El PET es de gran utilidad para determinar malignidad de nódulos y masas pulmonares, evitando cirugías innecesarias y permitiendo una correcta etapificación, pues evalúa también lesiones a distancia Background: The diagnosis and staging of pulmonary lesions with positron emission tomography (PET) with 18fluorodeoxyglucose (FDG) helps in the selection of the optimal therapy. Aim: To analyze the usefulness of FDG PET in the characterization of pulmonary nodules. Patients and Methods: Fifty eight patients referred for the assessment of a pulmonary nodule or mass (aged 62 ± 7 years, 28 males, 40% smokers), were studied. The imaging study was perfomed in the fasting state injecting 13 mCi of 18FDG. Pre injection blood glucose was 101 ± 5 mg/dl. Whole body images were acquired with visual analysis of coronal, sagittal and trans axial slices and three dimensional images. The standardized uptake value (SUV) was also calculated. Results: Pulmonary lesions were hypermetabolic in 22 patients (38%) and in the rest, there was no evidence of tumor activity. Extrapulmonary lesions were detected in 24% of patients. The size of the nodules ranged from 0.5 to 7 cm. in diameter. Those with positive PET had lesions over 0.8 cm diameter. In 12 of 16 patients with pathological study, the presence of cancer was confirmed. Two patients had false positive images. One had an abscessed Schwanoma and the other, a hamartoma. Two patients with PET images not suspicious of tumor, were operated and the pathology confirmed the absence of cancer. In the rest of patients with a negative study, the clinical follow up has been uneventful. In one patient with multiple hypermetabolic lesions with a pattern suggestive of sarcoidosis, the diagnosis was pathologically confirmed. Conclusions: FDG PET is useful for the characterization of pulmonary lesions and nodules

Positron-emission tomography (PET) with F18-fluorodeoxyglucose (FDG) is very helpful in the evaluation and management of lung lesions. It is specially useful for the characterization of solitary nodules, for the staging, evaluation of recurrence and therapeutic response in non-small cell lung cancer, for the evaluation of small cell lung cancer and for the assessment of pulmonary metastases. This article is a literature review on PET with FDG in lung cancer. A preliminary analysis of PET results at the Military Hospital in Santiago, Chile, is also presented.

Positron-emission tomography (PET) with F18-fluorodeoxyglucose (FDG) is very helpful in the evaluation and management of lung lesions. It is specially useful for the characterization of solitary nodules, for the staging, evaluation of recurrence and therapeutic response in non-small cell lung cancer, for the evaluation of small cell lung cancer and for the assessment of pulmonary metastases. This article is a literature review on PET with FDG in lung cancer. A preliminary analysis of PET results at the Military Hospital in Santiago, Chile, is also presented

We report a 38 year old female patient with a pancreatic mucinous cystadenocarcinoma. She presented at the onset with a peritoneal rupture that required emergency surgery. Five months later, the patient was subjected to a segmental pancreatectomy and splenectomy. One year later, the patient had a serious gastric bleeding secondary to a gastric ulcer. Due to a persistent increase in her CA 19-9 levels, a Positron Emission Tomography (PET) functional imaging with fluorine 18-deoxyglucose (F18FDG) was done. It showed an intense focal hypermetabolism in the gastric wall reported as a secondary tumour location. The patient was subjected to a total gastrectomy and Roux en Y anastomosis, with a good outcome. The pathological study confirmed the presence of a metastasis of an adenocarcinoma in the gastric wall. The relative value of CA 19-9 markers and FDG PET in pancreatic and gastric carcinomas is discussed.

We report a 38 year old female patient with a pancreatic mucinous cystadenocarcinoma. She presented at the onset with a peritoneal rupture that required emergency surgery. Five months later, the patient was subjected to a segmental pancreatectomy and splenectomy. One year later, the patient had a serious gastric bleeding secondary to a gastric ulcer. Due to a persistent increase in her CA 19-9 levels, a Positron Emission Tomography (PET) functional imaging with fluorine 18-deoxyglucose (F18FDG) was done. It showed an intense focal hypermetabolism in the gastric wall reported as a secondary tumour location. The patient was subjected to a total gastrectomy and Roux en Y anastomosis, with a good outcome. The pathological study confirmed the presence of a metastasis of an adenocarcinoma in the gastric wall. The relative value of CA 19-9 markers and FDG PET in pancreatic and gastric carcinomas is discussed.

The urea breath test (UBT) with a microdose of [14C] is a non-invasive and simple method for the assessment of gastric infection by Helicobacter pylori. The aim of this study was to compare the [14C]UBT with invasive methods widely used for assessment of H. pylori gastric infection, including histology with hematoxylin-eosin staining, the gastric smear technique using Giemsa staining, and the biopsy urease test.We evaluated patients referred to our clinic for elective upper gastrointestinal endoscopy excluding those on antibiotics and/or bismuth during the previous 4 weeks, patients on H+ blockers or H2 antihistamines during the previous 7 days, pregnant women, and patients who had undergone gastric surgery or had bleeding disorders. Eighty-nine patients ranging in age from 18-75 years were included in the final study population, 61 women and 28 men (mean age: 43(15 years).When histology alone was considered as the reference standard, sensitivity for the [14 C]UBT was 94%, with a specificity of 37%; when the Giemsa technique, sensitivity was 95%, and specificity 35%; and when the biopsy urease test, sensitivity was 94% and specificity 45%. With two or more invasive techniques together considered as the reference standard, the [14C]UBT had a sensitivity of 95%, with a specificity of 44%.[14C]UBT is an objective and reproducible technique, capable of sampling the whole gastric mucosa. It shows high sensitivity, but low specificity, which could be explained by limited gastric sampling plus subjective interpretation in the invasive techniques that are currently used as gold standard.