75SeHCAT scan in bile acid malabsorption in chronic diarrhoea. / Gammagrafía con 75SeHCAT en la diarrea crónica por malabsorción de ácidos biliares.

Chronic diarrhoea is a common entity in daily clinical practice and it leads to a loss in these patients quality of life. It may be the main symptom of multiple ethiologies including bile acid malabsorption (BAM) which has a comparable prevalence to celiac disease. The BAM results from imbalances in the homeostasis of bile acids in the enterohepatic circulation. It can be a consequence of ileal disease or ileal dysfunction (BAM type i), it can be considered idiopathic or primary (BAM type ii) or associated with other gastrointestinal entities (BAM type iii). Among the different diagnostic methods available, 75SeHCAT study is the primary current method due to its sensitivity, specificity, safety and low cost. The main disadvantage is that it's not available in all countries, so other diagnostic methods have appeared, such as serum measurement of FGF19 and C4, however they are significantly more complex and costly. The first-line treatment of bile acid diarrhoea is bile acid sequestrant, such as cholestyramine, which can be difficult to administer due to its poor tolerability and gastrointestinal side effects. These are less prominent with newer agents such as colesevelam. In summary, the BAM is a common entity underdiagnosed and undertreated, so it is essential to establish a diagnosis algorithm of chronic diarrhoea in which the 75SeHCAT study would be first or second line in the differential diagnosis of these patients.

Validation of stationary phases in (111)In-pentetreotide planar chromatography.

INTRODUCTION: Since Pall-German stopped manufacturing ITLC-SG, it has become necessary to validate alternative stationary phases. OBJECTIVE: To validate different stationary phases versus ITLC-SG Pall-Gelman in the determination of the radiochemical purity (RCP) of (111)In-pentetreotide ((111)In-Octreoscan) by planar chromatography. MATERIAL AND METHODS: We conducted a case-control study, which included 66 (111)In-pentetreotide preparations. We determined the RCP by planar chromatography, using a freshly prepared solution of 0,1M sodium citrate (pH 5) and the following stationary phases: ITLC-SG (Pall-Gelman) (reference method), iTLC-SG (Varian), HPTLC silica gel 60 (Merck), Whatman 1, Whatman 3MM and Whatman 17. For each of the methods, we calculated: PRQ, relative front values (RF) of the radiopharmaceutical and free (111)In, chromatographic development time, resolution between peaks. We compared the results obtained with the reference method. The statistical analysis was performed using the SPSS program. The p value was calculated for the study of statistical significance. RESULTS: The highest resolution is obtained with HPTLC silica gel 60 (Merck). However, the chromatographic development time is too long (mean=33.62minutes). Greater resolution is obtained with iTLC-SG (Varian) than with the reference method, with lower chromatographic development time (mean=3.61minutes). Very low resolutions are obtained with Whatman paper, essentially with Whatman 1 and 3MM. Therefore, we do not recommend their use. CONCLUSIONS: Although iTLC-SG (Varian) and HPTLC silica gel 60 (Merck) are suitable alternatives to ITLC-SG (Pall-Gelman) in determining the RCP of (111)In-pentetreotide, iTLC-SG (Varian) is the method of choice due to its lower chromatographic development time.

[Response of thyroglobulin, anti-thyroglobulin antibodies, TSH, FT4 and total T3 after rhTSH stimulation in differentiated thyroid carcinoma]. / Respuesta de tiroglobulina, anticuerpos antitiroglobulina, TSH, FT4 y T3 total tras estimulación con rhTSH en carcinoma diferenciado de tiroides.

OBJECTIVE: To analyse the behaviour of serum thyroglobulin (Tg), antithyroglobulin antibodies (TgAb), thyrotropin (TSH), free thyroxine (FT4) and total triiodothyronine (TT3) levels at each time during the rhTSH stimulation protocol in patients with differentiated thyroid carcinoma (DTC). MATERIALS AND METHODS: We carried out 117 rhTSH stimulations in DTC patients. We determined the serum levels of Tg, TgAb, TSH, FT4 and TT3 at baseline and 24, 48 and 96 hours after beginning stimulation, using RIA or IRMA. The software program SPSS 15.0 was used for statistical analysis of data. RESULTS: We found statistically significant differences between the mean Tg values at different times (2.08 ng/ml baseline; 2.64 ng/ml at 24 hours; 4.98 ng/ml at 48 hours; 6.59 ng/ml at 96 hours), reaching maximum values at 96 hours. During this time, we observed the highest percentage of pathological values. After administration of rhTSH, there was a significant increase in the mean TSH value (98.88 mIU/l at 24 hours; 111.10 mIU/l at 48 hours). The mean TSH value at 96 hours decreased approximately 5 times with respect to the mean 48 hour value. We did not observe changes in the TgAb, FT4 or TT3 levels. CONCLUSIONS: The assessment of Tg after rhTSH stimulation should be performed 96 hours after beginning stimulation. Administration of rhTSH causes a significant elevation in serum TSH levels, without modifying serum TgAb, FT4 or TT3 levels.

[Usefulness of thyroid scintigraphy in the therapeutic management of amiodarone-induced hyperthyroidism]. / Utilidad de la gammagrafía tiroidea en el manejo terapéutico del hipertiroidismo inducido por amiodarona.

UNLABELLED: Amiodarone-induced hyperthyroidism is relatively common in iodine-deficient regions. Two types have been described: type I, caused by increased synthesis and release of thyroid hormone in individuals with underlying thyroid disease, can be treated with antithyroid drugs or radioiodine; and type II, a destructive thyroiditis responsive to corticoid therapy but not to antithyroid drugs. It can be difficult to distinguish between the two types, and cases of mixed types have been reported. OBJECTIVE: to assess the usefulness of thyroid scintigraphy in amiodarone-induced hyperthyroidism. MATERIALS AND METHODS: 27 consecutive patients (13 females) with amiodarone-induced hyperthyroidism. Mean age was 65 years (range: 39-89). All patients underwent 99mTc-pertechnectate thyroid scintigraphy and were classified according to the qualitative estimation of radiotracer uptake: type I (increased / normal uptake): 9 patients, all of whom responded to antithyroid drugs or radioiodine, except one patient with sub-clinical hyperthyroidism who received no therapy; type II (very low or undetectable uptake): 13 patients, 11 of whom responded to discontinuation of amiodarone or prednisone therapy (2 patients). Hyperthyroidism was resistant in 2 patients and required antithyroid drugs or potassium perchlorate; mixed type (low uptake but with underlying thyroid pathology): 5 patients, with variable evolution; all needed antithyroid drugs, one required subtotal thyroidectomy, and another radioiodine treatment. CONCLUSION: thyroid scintigraphy can establish the correct therapeutic approach in most cases of amiodarone-induced hyperthyroidism, making it essential in the clinical management of these patients.

Utilidad de la gammagrafía tiroidea en el manejo terapéutico del hipertiroidismo inducido por amiodarona / Usefulness of thyroid scintigraphy in the therapeutic management of amiodarone-induced hyperthyroidism

El hipertiroidismo por amiodarona (HA) es una entidad relativamente frecuente en zonas dietéticamente deficitarias de yodo. Se describen dos entidades: la tipo I, causada por excesiva síntesis de hormona tiroidea en pacientes con patología tiroidea subyacente que responde a antitiroideos o al radioyodo, y la tipo II, producida por tiroiditis destructiva inflamatoriaque responde a los corticoides, pero no a los antitiroideos. La diferencia entre ambos tipos puede ser difícil, y se han descrito formas intermedias. Objetivo. Valorar la utilidad de la gammagrafía tiroidea en pacientes con HA. Material y métodos. Veintisiete pacientes consecutivos (13 mujeres) con 39-89 años e HA. Se realizó gammagrafía tiroidea con 99mTc-pertecnectato, clasificando al paciente en subgrupos, en función de una valoración cualitativa de la captación gammagráfica. Resultados: patrón tipo I (captación tiroidea normal o incrementada): 9 pacientes. Todos respondieron a la terapia con antitiroideos o radioyodo, excepto un paciente con hipertiroidismo subclínico que no recibió tratamiento; patrón tipo II (captación inhibida): 13 pacientes. La mayoría (11 pacientes) remite al retirar la amiodarona (9) o con corticoides (2). Sólo en dos pacientes el hipertiroidismo fue resistente y obligó a la terapia con antitiroideos o perclorato potásico; patrón intermedio (5 pacientes) con captación empobrecida y patología tiroidea subyacente. Tuvieron una evolución variable, necesitando antitiroideos en todos los casos; además uno de ellos precisó tiroidectomía subtotal y otro tratamiento con radioyodo. Conclusiones. La gammagrafía tiroidea permite establecerla terapia a administrar en la mayoría de pacientes con HA, por lo que resulta una herramienta diagnóstica imprescindible en el manejo clínico de estos pacientes

Amiodarone-induced hyperthyroidism is relatively common in iodine-deficient regions. Two types have been described: type I, caused by increased synthesis and release of thyroid hormone in individuals with underlying thyroid disease, can be treated with antithyroid drugs or radioiodine; and type II, a destructive thyroiditis responsive to corticoid therapybut not to antithyroid drugs. It can be difficult to distinguish between the two types, and cases of mixed types have been reported.Objective. to assess the usefulness of thyroid scintigraphy in amiodarone-induced hyperthyroidism. Materials and methods. 27 consecutive patients (13 females) with amiodarone-induced hyperthyroidism. Mean age was 65 years (range: 39-89). All patients underwent 99mTcpertechnectate thyroid scintigraphy and were classified according to the qualitative estimation of radiotracer uptake: type I (increased / normal uptake): 9 patients, all of whom responded to antithyroid drugs or radioiodine, except one patient with sub-clinical hyperthyroidism who received no therapy; type II (very low or undetectable uptake): 13 patients, 11 of whom responded to discontinuation of amiodarone or prednisone therapy (2 patients). Hyperthyroidism was resistant in 2 patients and required antithyroid drugs or potassium perchlorate; mixed type (low uptake but with underlying thyroid pathology): 5 patients, with variable evolution; all needed antithyroid drugs, one required subtotal thyroidectomy, and another radioiodine treatment. Conclusion. thyroid scintigraphy can establish the correct therapeutic approach in most cases of amiodarone-induced hyperthyroidism, making it essential in the clinical management of these patients

[Quality assurance of the renal applications software]. / Control de calidad de las aplicaciones de procesado renal.

INTRODUCTION: The need for quality assurance of all technical aspects of nuclear medicine studies is widely recognised. However, little attention has been paid to the quality assurance of the applications software. Our work reported here aims at verifying the analysis software for processing of renal nuclear medicine studies (renograms). MATERIAL AND METHODS: The software tools were used to build a synthetic dynamic model of renal system. The model consists of two phases: perfusion and function. The organs of interest (kidneys, bladder and aortic artery) were simple geometric forms. The uptake of the renal structures was described by mathematic functions. Curves corresponding to normal or pathological conditions were simulated for kidneys, bladder and aortic artery by appropriate selection of parameters. RESULTS: There was no difference between the parameters of the mathematic curves and the quantitative data produced by the renal analysis program. CONCLUSION: Our test procedure is simple to apply, reliable, reproducible and rapid to verify the renal applications software.

Control de calidad de las aplicaciones de procesado renal / Quality assurance of the renal applications software

Objetivo. Todos los aspectos técnicos de los estudios de Medicina Nuclear deben ajustarse a un programa de garantía de calidad. Sin embargo, se ha prestado poca atención al control de calidad de las aplicaciones de procesado. Nuestro trabajo pretende verificar los programas de análisis empleados en el procesado de los estudios renales (renogramas). Material y métodos. Mediante software hemos construido un modelo dinámico sintético del sistema renal. El modelo consta de dos fases: perfusión y función. Los órganos de interés (riñones, vejiga y arteria aorta) fueron simulados mediante formas geométricas simples. Las captaciones de las estructuras renales vienen descritas por funciones matemáticas. Se simularon distintas curvas de actividad-tiempo de riñón, vejiga y arteria aorta correspondientes a situaciones normales y patológicas mediante la selección adecuada de parámetros. Resultados. No se ha observado ninguna diferencia entre los parámetros de las curvas matemáticas y los datos cuantitativos producidos por el programa de análisis renal. Conclusión. Nuestro procedimiento nos permite verificar los programas de procesado de los estudios renales de forma simple, fiable, reproducible y rápida

Introduction. The need for quality assurance of all technical aspects of nuclear medicine studies is widely recognised. However, little attention has been paid to the quality assurance of the applications software. Our work reported here aims at verifying the analysis software for processing of renal nuclear medicine studies (renograms). Material and methods. The software tools were used to build a synthetic dynamic model of renal system. The model consists of two phases: perfusion and function. The organs of interest (kidneys, bladder and aortic artery) were simple geometric forms. The uptake of the renal structures was described by mathematic functions. Curves corresponding to normal or pathological conditions were simulated for kidneys, bladder and aortic artery by appropriate selection of parameters. Results. There was no difference between the parameters of the mathematic curves and the quantitative data produced by the renal analysis program. Conclusion. Our test procedure is simple to apply, reliable, reproducible and rapid to verify the renal applications software