Respiratory muscle weakness in Addison's disease.

Comment Evidence of thyroid autoimmunity has often been noted in patients who develop hypothyroidism while receiving amiodarone.2 Between 30% and 50% of patients who have hypothyroidism induced by amiodarone iodine have antithyroid antibodies.' 2 Antithyroid antibodies are less common in patients who have hyperthyroidism induced by amiodarone iodine. Monteiro et al reported the development of antimicrosomal antibodies in six of 13 patients treated with amiodarone for one month. Two of these patients had slightly increased serum concentrations of thyroid stimulating hormone, and all were euthyroid with negative antibody titres six months after the amiodarone had been withdrawn. Rabinowe et al noted a high prevalence (60%) of antimicrosomal antibodies in 10 patients who received amiodarone, but no data are available for these patients before treatment.4 One of their patients developed hyperthyroidism while receiving amiodarone and showed a considerable increase in immune region associated antigen positive T cells, often found in patients who have Graves' disease, which resolved within three weeks of withdrawing the amiodarone. The results of our prospective study, however, which included patients treated with amiodarone for both short and long periods and from regions of differing ambient iodine intake show that amiodarone treatment does not seem to be associated with an increased incidence of antithyroid antibodies.