Influenza infection and Kawasaki disease

Xijing Huang, Ping Huang, Li Zhang, Xiaofei Xie, Shuliang Xia, Fang Gong, Jia Yuan, Liling Jin

The objective of this study was to investigate the possible link between influenza (Flu) infection and Kawasaki disease (KD). We examined the medical records of 1,053 KD cases and 4,669 influenza infection cases hospitalized at our institute from January 1, 2011 to December 31, 2013. Cases of KD with concomitant influenza infection formed the KD + Flu group. Each KD + Flu case was matched with 2 KD cases and 2 influenza infection cases, and these cases were assigned to the KD group and Flu group, respectively. The differences in the principal clinical manifestations, course of disease, incomplete KD rate, intravenous immunoglobulin (IVIG) resistance rate, and echocardiographic detection results between the KD + Flu group and KD group were compared. The fever durations and laboratory test results of these three groups were compared. 1) The seasonal variations of the KD + Flu group, KD group and Flu group were similar. 2) The morbidity rate of incomplete KD was higher in the KD + Flu group compared with the KD group. 3) Patients in the KD + Flu group exhibited a longer time to KD diagnosis compared with patients in the KD group. 4) The KD + Flu group exhibited the longest fever duration among the three groups. 5) The CRP and ESR values in the KD + Flu group were higher those in the Flu or KD groups. Concomitant influenza infection affects the clinical manifestations of KD and can impact the laboratory test results and the diagnosis and treatment of the disease. However, it remains unclear whether influenza contributes to KD etiology.