A Chinese case series of Yao syndrome and literature review

Yao syndrome (YAOS), formerly named NOD2-associated autoinflammatory disease, is a periodic disease characterized by fever, dermatitis, polyarthritis, distal extremity swelling, and gastrointestinal and sicca-like symptoms associated with specific NOD2 sequence variants. All patients in the literature were Caucasians. Herein, we report the first case series of YAOS in China to further expand the clinical and genetic characteristics of this disorder. A retrospective review of patients who were diagnosed with YAOS at our tertiary medical center was conducted. Three Han Chinese women with YAOS were included. Recurrent fever occurred in all patients and each febrile episode lasted several days to several weeks, and asymptomatic intervals ranged from several weeks to several months. Two patients experienced intermittent arthritis/arthralgia and abdominal pain, and one had sicca-like symptoms. None had dermatitis. Three variants in NOD2 were identified, including Q902K, R541P, and Y514H. The patients' symptoms significantly improved after treatment with glucocorticoids and/or sulfasalazine. YAOS exists in the Chinese population, and it may be a global disorder. Our patients appear to exhibit somewhat distinct clinical phenotypes from those in the Caucasian population, and three novel NOD2 variants have been identified in the disease.