Mixed connective tissue disease (MCTD) is a rare systemic autoimmune disease characterized by the main features of overlapping connective tissue diseases. The disease is also defined by the presence of anti-U1-ribonucleoprotein (RNP) antibodies and the Raynaud phenomenon. We report the administration of general anesthesia in a patient with MCTD. A 53-year-old female (height, 161.2 cm ; weight, 50.4 kg) was scheduled to receive a partial tongue resection under general anesthesia for the treatment of tongue cancer. Around 2000, swelling in both hands and Raynaud’s symptoms developed, and she was confirmed as being positive for the anti-U1-RNP antibody and was diagnosed with MCTD. The patient also developed interstitial pneumonia and idiopathic thrombocytopenic purpura. Because a decreased platelet count was observed in the preoperative evaluation, the doses of eltrombopag olamine and prednisolone were increased. A chest CT scan showed reticular ring shadows and ground-glass opacities in both lower lung fields. For the general anesthesia, steroid coverage was provided by the intravenous administration of hydrocortisone. To prevent exacerbation of the interstitial pneumonia, the oxygen concentrations were maintained at 60％ during induction and emergence and at 30％ during maintenance. Anesthetic induction was performed with remifentanil and propofol, and anesthetic maintenance was performed with sevoflurane and remifentanil. After the induction of anesthesia, the securement of a venous tract in the upper extremities was difficult. MCTD presents with a variety of clinical manifestations, including symptoms of various autoimmune diseases, and the severity of these manifestations varies greatly from person to person. Therefore, understanding the symptoms and severity of MCTD is an important component of perioperative management.
