Autoimmune thyroid disease with ulcerative colitis.

Two cases of co-existing thyroid disease and ulcerative colitis are reported. Thyroid disorder preceded ulcerative colitis in each case. The presence of acute colitis delayed and obscured the clinical diagnosis of thyrotoxicosis in one case and the colitis could not be controlled until her thyrotoxicosis was treated. Although the specific factors involved in this relationship are now known, an interplay of immunological factors is most probable.