RTN4RL2 and susceptibility to pneumonia measurement: Moreover, the expression of eight of these 30 DEPs (PECAM1, PGLYRP1, AHCY, BHMT, EML3, ICOSLG, IGHV3‐23 and RTN4RL2) clustered normal and pneumonia samples into one group and clustered KD samples into another group, which heightens the importance of these eight DEPs in KD.