Abstract: Objective: To analyze the clinical features of dermatomyositis (DM) complicated with thyroid dysfunction. Methods: The clinical and laboratory data including antibodies, C reactive protein (CRP), immunoglobulin and serum lipid levels of 195 patients with DM from 2010 to 2014. Results: Out of 195 patients, 56.41% patients had thyroid dysfunction and most of them suffered from subclinical hypothyroidism and low T3 syndrome. DM patients with thyroid dysfunction were more likely to have higher levels of CRP and IgG as well as Gottron sign, fever and erythema. There was no significant difference in the number of patients with internal organ involvement and tumors between the two groups. Conclusion: The subclinical thyroid dysfunction is high in the patients with DM and there may be a common immunological background in the two diseases.

Key words: dermatomyositis, hypothyroidism, immunology