RESUMEN
Perchlorate is known to suppress thyroid function by inhibiting uptake of iodide by the human thyroid at doses of 200 mg/day or greater. A study was conducted to investigate the potential effects of perchlorate in drinking water on thyroid function in newborns and school-age children. A total of 162 school-age children and 9784 newborns were studied in three proximate cities in northern Chile that have different concentrations of perchlorate in drinking water: Taltal (100 to 120 micrograms/L), Chañaral (5 to 7 micrograms/L), and Antofagasta (non-detectable: < 4 micrograms/L). Among schoolchildren, no difference was found in thyroid-stimulating hormone levels or goiter prevalence among lifelong residents of Taltal or Chañaral compared with those of Antofagasta, after adjusting for age, sex, and urinary iodine. No presumptive cases of congenital hypothyroidism were detected in Taltal or Chañaral; seven cases were detected in Antofagasta. Neonatal thyroid-stimulating hormone levels were significantly lower in Taltal compared with Antofagasta; this is opposite to the known pharmacological effect of perchlorate, and the magnitude of difference did not seem to be clinically significant. These findings do not support the hypothesis that perchlorate in drinking water at concentrations as high as 100 to 120 micrograms/L suppresses thyroid function in newborns or school-age children.
Asunto(s)
Hipotiroidismo/inducido químicamente , Hipotiroidismo/epidemiología , Percloratos/efectos adversos , Compuestos de Sodio/efectos adversos , Contaminación del Agua/efectos adversos , Distribución por Edad , Niño , Preescolar , Chile/epidemiología , Intervalos de Confianza , Recolección de Datos , Ingestión de Líquidos , Monitoreo del Ambiente , Monitoreo Epidemiológico , Estudios de Factibilidad , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Modelos Lineales , Modelos Logísticos , Masculino , Oportunidad Relativa , Percloratos/análisis , Factores de Riesgo , Distribución por Sexo , Compuestos de Sodio/análisis , Pruebas de Función de la Tiroides , Contaminación del Agua/análisisRESUMEN
OBJECTIVE: To report on cases of diabetic cataracts in a paediatric and adolescent population. METHODOLOGY: Medical histories of children and adolescents attending the Royal Children's Hospital Diabetes Service who had developed cataracts between 1981 and 1996 were examined. RESULTS: Nine cases of diabetic cataracts have been managed over the 16-year time frame. Two cases presented at diagnosis of insulin-dependent diabetes mellitus (IDDM) and one 3 weeks after. The remaining six presented 1.7-13 years (mean 5.17+/-4.02) after diagnosis of IDDM. All but one had exhibited poor control of their diabetes with high HbA1C values. CONCLUSIONS: Cataracts occurring in the paediatric and adolescent population, though uncommon, lead to marked morbidity. It is recommended that all children have an ophthalmological examination at diagnosis, particularly if they have had a long duration of symptoms before diagnosis. Persistently poor diabetes control and/or blurred vision are indications for prompt ophthalmological review.