[The TRH test in simple goiter]

The TSH response to TRH and the increase in serum T3 after TRH infusion were measured in 25 euthyroid patients with non toxic goiter. On the ground of anatomic characters we divided the goitrous patients into 3 groups: subjects with diffuse goiter, with multinodular and with uninodular goiter; delta TSH and delta T3 did not differ significantly in the three groups. On the contrary, either absent hormonal increase (preclinic hyperthyroidism), or exceeding response (preclinic hypothyroidism), or normal response (real euthyroidism) were found in the different patients of a same group. Therapeutic implications of such a finding were taken into consideration.