endemic goiter, an enlargement of the thyroid gland caused by the intake of inadequate amounts of dietary iodine. Iodine deprivation leads to diminished production and secretion of thyroid hormone by the gland. The pituitary gland, operating on a negative feedback system, senses the deficiency and secretes increased amounts of thyroid-stimulating hormone, causing hyperplasia and hypertrophy of the thyroid gland. ▪ OBSERVATIONS: The goiter may grow during the winter months and shrink during the summer months when the person eats more iodine-containing fresh vegetables. Initially the goiter is diffuse; later it becomes multinodular. ▪ INTERVENTIONS: The use of iodized salt is a prophylactic treatment. Desiccated thyroid given orally may prevent further growth of adult goiters and may reduce the size of diffuse goiters. ▪ PATIENT CARE CONSIDERATIONS: Endemic goiter occurs occasionally in adolescents at puberty and widely in population groups in geographic areas in which limited amounts of iodine are present in soil, water, and food. A large goiter may cause dysphagia, dyspnea, tracheal deviation, and cosmetic problems.
