Enfermedad de Graves infanto-juvenil: tratamiento alternativo con 131I / Graves disease in childhood and youth: alternative treatment with 131I

Entre 1982 y 1988 se realizó tratamiento y seguimiento de 22 pacientes con enfermedad de Graves infanto-juvenil (13f y 90m). Las edades de comienzo de la enfermedad oscilaron entre 4 y 17 años (x12 a 10m). En todos los casos se efectuó tratamiento con metimazol (MMI) y una vez alcanzado el eutiroidismo, conMMI + hormona tiroidea, con una duración de 1 a 2 meses (m) a 6 años (a). Siete pacientes remitieron con esta terapéutica, 3 abandonaron la consulta, 6 continúan en tratamiento y en 7 se administró una dosis terapéutica (DT) de I (3). En estos últimos (4f y 3m), la edad al recibir la DT oscilaba entre 15 y 20 a.(x17a. 1m.). En 4 casos se indicó el I por remisión luego de administrar MMI por lapsos mayores a 4 años, en 1 caso por recidiva al año de suspender el MMI y en 2 por no ccumplimiento del tratamiento. Las DT variaron entre 4 y 15 mCi (x7,322). Cuatro pacientes remitieron con la 1ra. dosis, 2 requirieron una 2º DT y en 1 caso fue necesario suministrar una 3ra. Con un seguimiento de 10m. a 2 a. 1 m., 3 pacientes permanecen eutiroideos y 4 presentan hipotiroidismo, que se manifstó entre 2 y 10 m. post DT. No se observaron alteraciones hematológicas, nódulos tiroideos ni aparición o agravamiento de oftalmopatía preexistente. Consideramos que la DT de I(3) constituye un recurso alternativo de alta eficacia en los pacientes infanto-juveniles en quienes ha fracasado la terapéutica antitiroidea, en aquellos en que no se logra la continuidad del tratamiento o ante la aparición de efectos colaterales graves (AU)

Reproducibility and variability of the arginine test in normal adults: comparison between sexes

The biochemical diagnosis of growth hormone deficiency in adults (AGHD) remains controversial, mainly as regards stimulation tests and suggested cut-off lines. The insulin tolerance test proved to be the most effective growth hormone (GH) secretagogue in normal males, but a poor intra-individual reproducibility has been reported. Given the safety of the arginine (AST), we decided to evaluate the incidence of false negatives (non responder normal subjects), its reproducibility and variability. Twenty five healthy non-obese volunteers (16 males, 9 females) with a chronological age range between 19 and 40 years, (mean: 29.8) were evaluated. AST was performed (0.5 g/kg IV infusion for 30 min), measuring GH (IRMA) at baseline (B), 30, 60 and 90 minutes, and it was repeated in the same subject 7 to 30 days later; in females both tests were performed in the early follicular phase. Results (median and range) were: 1st test B: 0.61 (0.35-22.60) mug/L; maximal response (Mx Resp) 10.00 (0.48-48.80 mug/L 2nd test B:0.50 (0.38-27.0) mug/L; Mx Resp 11.00 (0.50-47.70) mug/L. The statistical evaluation (Wilcoxon signed rank test) showed no differences between B vs. B and Mx Resp vs Mx Resp. Separated by Sex, males showed: 1st test: B 0.45 (0.35-4.30) mug/L; Mx Resp 6.30 (0.48-48.80) mug/L. 2nd test B 0.46 (0.38-8.80) mug/L; Mx Resp 10.90 (0.50-47.70) mug/L, while females showed 1st test: B 5.20 (0.50-22.60) mug/L; mx Resp 14.00 (3.50-36.70) mug/L 2nd test B 3.60 (0.75-27.00) mug/L; Mx Resp 13.00 (3.70-28.10) mug/L. The statistical comparison (Mann Whitney test) showed significant differences between both sexes in basal values of the first and second test (p<0.001), and in the naximal response of the first test (p<0.03). The statistical analysis did not show significant differences in delta increases between males and females, neither in the first AST nor in the second one. Considering GH values =3 mug/L as a positive response, 4 males exhibited insufficient responses in both tests and other 2 males showed discordant results between tests 1 and 2. All females evaluated produced responses above 3 mug/L in both tests. The results of the present study demonstrate that, particularly in men, AST has no clear limit of normality while it shows good intra-individual reproducibility. In conclusion, at present the biochemical diagnosis of AGHD requires a clear and precise standardization which includes all variables that can modify the GH response to the stimulus used. (AU)