COVID-19 Acute and Chronic Manifestations in Hospitalized Children

Background and Objectives: While children with coronavirus disease 2019 (COVID-19) often exhibit milder symptoms than adults, understanding hospitalization-related manifestations is critical for optimizing care. Methods: This retrospective cross-sectional study evaluates short- and long-term manifestations and their association with disease severity in 295 hospitalized pediatric patients (< 18 years) at two Tehran hospitals (2021 - 2022), confirmed via polymerase chain reaction (PCR) and clinical criteria. Disease severity was classified per World Health Organization (WHO) guidelines (mild, moderate, severe, critical), with follow-ups at ≤ 2 weeks (short-term) and 12 weeks (long-term). Results: Participants (mean age 3.04 ± 2.98 years; 40.3% female) predominantly had mild (67.5%), moderate (27.1%), or severe (5.4%) disease. Mortality rate was 1.01% (3 from 295 cases). Fever (79.66%) was the most common initial symptom. Short-term manifestations included general (e.g., fatigue, sleep disorders: 34.23%), pulmonary (32.54%), and hematological (26.77%) issues. Long-term manifestations decreased to general (20.01%), pulmonary (16.06%), and hematological (7.79%) manifestations, with fatigue persisting most frequently. Univariable analysis linked disease severity to pulmonary, hematological, and general manifestations in both periods (P < 0.05). However, multivariable analysis retained only pulmonary manifestations (short- and long-term) and short-term general manifestations as significant (P < 0.05). Disease severity correlated with prolonged hospitalization, intensive care unit (ICU) admission, readmission, and mortality in univariable models (all P < 0.05), though these associations diminished in multivariable adjustments (P > 0.05). Conclusions: Disease severity significantly predicts pulmonary manifestations and fatigue in hospitalized children. Prioritized follow-up for moderate-to-severe cases may mitigate prolonged morbidity. These findings emphasize targeted monitoring of high-risk pediatric populations to address post-COVID sequelae, underscoring the need for tailored healthcare strategies despite generally milder acute presentations.