A 63-year-old Chinese female with mixed connective tissue disease who suffered from renal crisis

Abstract

Mixed connective tissue disease (MCTD) is a rare autoimmune disorder. We present a case of a Chinese female who has been admitted to our hospital on eight separate occasions. Her initial symptoms involved internal organs including the lung and heart. Due to the presence of anti-U1RNP antibodies and other clinical features, a diagnosis of MCTD was considered. Throughout her first to seventh admissions, her serum creatinine levels remained normal. During her eighth hospitalization, her renal function deteriorated rapidly, culminating in renal crisis. Chest computed tomography (CT) confirmed pulmonary edema, necessitating hemodialysis. Her interleukin (IL)-6 level increased significantly during throughout hospitalizations. The patient responded well to treatment with an IL-6 receptor antagonist (IL-6RA). This case raises the question of whether IL-6 could serve as a potential biomarker for predicting renal crisis incidence in MCTD patients, a topic warranting further investigation in the future.