METHODS: The International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) COVID-19 database was queried to include children under 19 years of age admitted to hospital from January 2020 to April 2021 with suspected or confirmed COVID-19 diagnosis. Univariate and multivariable analysis of contributing factors for mortality were assessed by country group (HICs vs LMICs) as defined by the World Bank criteria.

RESULTS: A total of 12 860 children (3819 from 21 HICs and 9041 from 15 LMICs) participated in this study. Of these, 8961 were laboratory-confirmed and 3899 suspected COVID-19 cases. About 52% of LMICs children were black, and more than 40% were infants and adolescent. Overall in-hospital mortality rate (95% CI) was 3.3% [=(3.0% to 3.6%), higher in LMICs than HICs (4.0% (3.6% to 4.4%) and 1.7% (1.3% to 2.1%), respectively). There were significant differences between country income groups in intervention profile, with higher use of antibiotics, antivirals, corticosteroids, prone positioning, high flow nasal cannula, non-invasive and invasive mechanical ventilation in HICs. Out of the 439 mechanically ventilated children, mortality occurred in 106 (24.1%) subjects, which was higher in LMICs than HICs (89 (43.6%) vs 17 (7.2%) respectively). Pre-existing infectious comorbidities (tuberculosis and HIV) and some complications (bacterial pneumonia, acute respiratory distress syndrome and myocarditis) were significantly higher in LMICs compared with HICs. On multivariable analysis, LMIC as country income group was associated with increased risk of mortality (adjusted HR 4.73 (3.16 to 7.10)).

DESIGN: Prospective multicenter observational study from June 2020 to September 2022.

SETTING: Fifteen PICUs in PACCMAN.

PATIENTS: All children younger than 18 years old diagnosed with pneumonia and admitted to the PICU.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: Clinical, microbiologic, and outcome data were recorded. The primary outcome was PICU mortality. Univariate and multivariable logistic regression was performed to investigate associations between PICU mortality and explanatory risk factors on presentation to the PICU. Among patients screened, 846 of 11,778 PICU patients (7.2%) with a median age of 1.2 years (interquartile range, 0.4-3.7 yr) had pneumonia. Respiratory syncytial virus was detected in 111 of 846 cases (13.1%). The most common bacteria were Staphylococcus species (71/846 [8.4%]) followed by Pseudomonas species (60/846 [7.1%]). Second-generation cephalosporins (322/846 [38.1%]) were the most common broad-spectrum antibiotics prescribed, followed by carbapenems (174/846 [20.6%]). Invasive mechanical ventilation and noninvasive respiratory support was provided in 438 of 846 (51.8%) and 500 of 846 (59.1%) patients, respectively. PICU mortality was 65 of 846 (7.7%). In the multivariable logistic regression model, age (adjusted odds ratio [aOR], 1.08; 95% CI, 1.00-1.16), Pediatric Index of Mortality 3 score (aOR, 1.03; 95% CI, 1.02-1.05), and drowsiness (aOR, 2.73; 95% CI, 1.24-6.00) were associated with greater odds of mortality.