78 Clinical characteristics and outcomes of hospitalized children with acute respiratory infections in 2022-2023: the READAPT-kids study

Abstract Background Respiratory tract infections (RTI) are amongst the five leading causes of death in children in Canada. After relaxation of public health interventions for COVID-19, there was a significant increase in hospital admissions in children with RTI. The epidemiology of these cases, causative viral pathogens, severity of illness, and type of complications are poorly described. Objectives To describe the epidemiology and outcomes of children under 18 years with RTI between July 2022 and June 2023. Design/Methods A retrospective observational cohort study in hospitalized children at two tertiary Canadian centers with an acute RTI. The primary outcome was intensive care unit (ICU) admission. Characteristics of the cohort are described. Regression analyses for risk factors for ICU admission will be performed (data not presented in abstract) Results The median age of 2603 patients was 2.6 (IQR: 0.9-5.1) and 59% were males. Neurologic/genetic diagnoses were the most common comorbidity. Children presented after a median of 4 (IQR: 2-6) days of symptoms with a median of 5 (IQR: 4-6) symptoms. Common symptoms included cough (n=2157, 83%), fever (n=1814, 70%), and increased work of breathing (n=1780, 68%). Most patients had viral testing performed (88%); with one virus identified in 1451 children (63%), two in 288 patients (13%), and three or more in 48 children (2%). In those tested, positive tests for RSV (n=692, 30%) and Rhinovirus/Enterovirus (n=582, 25%) were most common. 653 (25%) patients required an ICU admission. RSV (n=223, 34%) and Rhinovirus/Enterovirus (n=156, 24%) were the most common etiologies in patients admitted to ICU. Median duration of PICU admission was 3 (IQR: 1-6) days, with 41% of patients remaining in ICU for 4 or more days. Three quarters (n=481) of the patients admitted to PICU required non-invasive/invasive mechanical ventilation. Acute respiratory distress syndrome and cardiac complications developed in 40 (2%) and 76 (3%) patients, respectively. Positive blood culture for bacteria implicated in pneumonias were detected in 58 (2%) children. Median length of hospital stay was 3 (IQR: 1-6) days. Only 7% of patients had an emergency department visit within 30 days after discharge. 39 patients (1%) died. Conclusion After the relaxation of public health interventions, RTI related hospital admissions were in young children and over half of patients were positive for RSV and Rhinovirus/Enterovirus. While most admissions were short, one-quarter of children were admitted to PICU.