Valores normales de captación de 131Yodo de 2 y 24 horas

Abstract

Background: Radiolabeled ioding uptake is a useful tool in the study of thyroid diseases. Aim: To obtain normal values for (131)Iodine thyroid uptake in health 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 esamination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral (131)Idose was 5-10 mu Ci, 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) and 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 <0.02). 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 2h (5.0+/-1.7 and 6.0+/-1.8, respectively, p <0.02) and at 24 h (14.9+/-4.4 and 17.6+/-4.9%, respectively, p <0.01). Conclusions: 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 slightlynin subjects aged more than 40 years.