OBJECTIVE To explore and analyze the clinical characteristics and risk factors of critical influenza in children.

METHODS A retrospective analysis was conducted on the clinical data of children with influenza admitted to Nanjing Children′s Hospital from Jun. 2023 to Jan. 2025. The patients were divided into a critical group and a non-critical group based on the severity of their condition. Univariate and multivariate logistic regression analyses were used to identify the risk factors associated with critical influenza in children.

RESULTS Among the 289 children, 84 were in the critical group and 205 were in the non-critical group. Children in the critical group had a higher proportion of fatigue and limb pain (23.80%), neurological symptoms (70.24%) and concurrent pathogen infections (52.38%) than those in the non-critical group (P < 0.05). Indicators such as C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), procalcitonin (PCT), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CKMB) were elevated (P < 0.05). Multivariate logistic regression results showed that neurological symptoms (OR=6.371, 95%CI: 1.651 to 24.592), concurrent pathogen infections (OR=4.861, 95%CI: 1.316 to 17.957), elevated NLR (OR=1.178, 95%CI: 1.057 to 1.314), elevated PCT (OR=4.345, 95%CI: 1.446 to 13.057), elevated ALT (OR=1.065, 95%CI: 1.018 to 1.114), elevated LDH (OR=1.028, 95%CI: 1.017 to 1.040) and elevated CKMB (OR=1.043, 95%CI: 1.014 to 1.072) were risk factors for critical influenza.

CONCLUSIONS The risk of critical influenza is higher when neurological symptoms, concurrent pathogen infections, elevated NLR, PCT, ALT, LDH and CKMB are present. Targeted intervention measures should be provided as early as possible based on these findings.