D3.523 - Early childhood: a risk predictor for post-COVID-19 pulmonary sequelae in children

Although SARS-CoV-2 infection is generally milder in children, post-infectious pulmonary complications may occur even after asymptomatic or mild forms. The medium- and long-term bronchopulmonary consequences of pediatric COVID-19 remain insufficiently elucidated, particularly the role of age as a risk factor. Computed tomography (CT), especially HRCT, represents the reference method for assessing post-COVID-19 pulmonary involvement. The aim is to evaluate the significance of the child's age in lung damage from COVID-19 infection at evolutionary stages.

A descriptive, retrospective and prospective study included 81 children aged 0–17 years, hospitalized in the Pulmonology Clinic of the Mother and Child Institute (IMSP), during 2021–2022. All patients underwent chest CT at a mean interval of 2.34 ± 0.32 months after SARS-CoV-2 infection.

Pathological pulmonary CT findings were identified in 53 children (65.4%; 95% CI 55.6–74), while 28 children (34.6%; 95% CI 26–44.3) showed normal imaging. The mean age of the study group was 3.47 ± 0.53 years. Children with pulmonary involvement had a mean age of 3.49 ± 0.69 years, compared to 3.43 ± 0.81 years in those without abnormalities. Infants accounted for the highest proportion of cases with pulmonary involvement (45.3%), followed by toddlers (26.4%) and school-aged children (20.8%), whereas preschool children had the lowest frequency (7.5%). These differences were statistically significant (χ² = 159, p < 0.001). Bilateral involvement predominated (62.3%), with mainly basal distribution (segments S6, S8, S10). Pulmonary consolidations were the most frequent lesions (71.69%), followed by fibrotic changes (58.49%, predominantly in infants—70.83%), atelectasis (37.73%), ground-glass opacities (16.98%), pleuro-pulmonary/pleuro-diaphragmatic adhesions (15.09%), and air bubbles (7.54%).

Young age represents a major risk predictor for post-COVID-19 pulmonary involvement in children. Infants and young children are the most vulnerable to the development of persistent pulmonary lesions, predominantly bilateral and basal, with imaging features suggestive of post-viral interstitial lung involvement. These findings support the need for medium- and long-term clinical and imaging follow-up of children after SARS-CoV-2 infection, particularly those of younger age.