Clinical features, investigations and pathology in surgically treated thyrotoxicosis.

A retrospective study was conducted on 41 thyrotoxic patients operated from January 1986 to June 1992 in Alexandra Hospital. One had multinodular goitre, and the rest had autoimmune thyroid diseases. Analysis of the histopathological features of the 40 patients with autoimmune thyroid diseases revealed that 32 had Graves' disease, four had Hashimoto's thyroiditis and four had a mixed form of Graves' disease and Hashimoto's thyroiditis. Only 14 out of 32 patients had eye and/or cutaneous manifestation of Graves' disease. None of the patients with Graves' disease developed hypothyroidism over a mean follow-up period of two years post-operatively, whereas one out of four Hashimoto's thyroiditis and two out of the four with the mixed form of Graves' and Hashimoto's thyroiditis had hypothyroidism after surgery. We conclude that it may be difficult to make a diagnosis of Hashimoto's thyroiditis in the early phase when it presents with thyrotoxicosis. Besides, there are cases with a mixed form of both Graves' and Hashimoto's thyroiditis. However, it is important that the diagnosis of Hashimoto's thyroiditis be made before surgery, otherwise progression to hypothyroidism would be accelerated.