Thyroid volume influences serum calcitonin levels in a thyroid-healthy population: results of a 3-assay, 519 subjects study.

Background: We aimed to assess determinants for serum calcitonin (CT) levels and to define reference ranges for different CT immunoassays integrating thyroid ultrasonography (TUS) and conventional clinical and biochemical criteria to select the reference population.

Methods: Five hundred and nineteen thyroid-healthy subjects were included in this prospective cross-sectional population study. Thyroid volume was measured by TUS, while serum CT levels were measured by three different immunoassays.

Respiratory health effects and immunological response to Thermoactinomyces among sugar cane workers in Nicaragua.

Specific sensitization and respiratory effects associated with the inhalation of sugar cane dust were evaluated in a group of 51 Nicaraguan workers exposed to bagasse. A questionnaire interview, lung function test, serum precipitin tests for Thermoactinomyces sacchari and T. vulgaris, and immunoglobulin E tests for specific environmental allergens were performed for each worker.