摘要This case report described a 61-year-old woman who presented with dizziness, headache, muscle ache, diplopia, and vomiting who lost consciousness. Upon hospital admission, the levels of high-sensitivity cardiac troponin I and partial pressure of carbon dioxide were increased markedly. Loss of consciousness occurred twice after removal of invasive ventilator support. Coronary angiography demonstrated no stenosis in coronary arteries. Ultrasonography revealed inactivity of respiratory muscles. Oculomotor disturbance and autonomic-nerve dysfunctions were observed. Serum antibody against glutamic acid decarboxylase was positive. The rare phenotypes of persistent stiffness of muscles in the neck, face, bilateral upper and lower limbs were observed. The patient was diagnosed with fulminant myocarditis complicated by Stiff-person syndrome. Immunomodulatory treatment (glucocorticoids and immunoglobulins) elicited satisfactory therapeutic effects. In this case report, it was found that fulminant myocarditis and Stiff-person syndrome shared a common pathogenesis: "cytokine storm". Such patients may benefit from early treatment with immunomodulatory agents.