1. Department of Pediatrics, West China Second Hospital, Sichuan University, No. 20, Section 3, Renmin Nanlu, Chengdu, Sichuan 610041, China
2. Department of Pediatrics, The Medical Center of Dujiangyan, Chengdu 611830, China
3. Department of Pediatrics, Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, Chengdu 610072, China