Research report: Clinical characteristics and half-year outcomes of 53 children with severe adenovirus pneumonia complicated with encephalitis or encephalopathy

A retrospective study of 53 children with severe adenovirus pneumonia complicated by encephalitis or encephalopathy found that 50 children, or 94.3%, survived and were followed for approximately six months. The study examined children admitted to the Respiratory Department of Children’s Hospital of Chongqing Medical University in 2019. Researchers retrospectively analyzed the clinical characteristics, laboratory results, treatment and follow-up outcomes of the 53 children with severe adenovirus pneumonia complicated by encephalitis or encephalopathy.

For comparison, they selected 78 children with severe adenovirus pneumonia but without encephalitis or encephalopathy. Because this was a single-center retrospective analysis, the findings describe associations in these hospitalized groups and do not establish the independent effects of treatment or the broader course of adenovirus infection in children. The median age of the children with encephalitis or encephalopathy was 18.0 months, with ages reported as 7.5–37.0 months, and 32 of the 53 children, or 60.4%, were male.

Altered mental status was common: 48 children, or 90.6%, had listlessness, 33, or 62.3%, had dysphoria, and 25, or 47.2%, had hypersomnia. Seven children, representing 13.2% of the group, had seizures. Children with encephalitis or encephalopathy had different laboratory profiles from controls.

Their median leukocyte count was 7.39 × 10^9/L, median procalcitonin concentration was 1.885 ng/mL, and median lactate dehydrogenase concentration was 980.50 U/L. The corresponding differences from the control group were significant, with P values of 0.011, 0.001 and less than 0.001. Nasopharyngeal adenovirus load did not differ significantly between the groups. Leukopenia, hypoproteinemia, liver function impairment, coagulopathy and anemia were also more frequent among children with encephalitis or encephalopathy.

These findings show differences in measured clinical characteristics rather than evidence that any one laboratory abnormality caused the neurological complication. Respiratory support was common in the affected group. Treatment records also showed that 49 children, or 92.45%, received gamma globulin, 28, or 52.83%, received albumin, and 14, or 26.42%, received a blood transfusion.

The study documents treatment use but does not determine whether any of these interventions affected survival or later outcomes. At approximately six months, bronchiolitis obliterans was present in 19 of 50 survivors in the affected group, compared with 9 of 78 controls, or 11.54% (P = 0.001). Overall, the results show a cohort characterized by severe respiratory illness, altered mental status and frequent mechanical ventilation, with generally favorable reported neurological outcomes at six months but a substantial burden of pulmonary sequelae.

The retrospective design, single-center setting and small groups limit causal interpretation and generalization beyond the studied population.

Subject of Research: Six-month clinical and pulmonary outcomes in children with severe adenovirus pneumonia complicated by encephalitis or encephalopathy

Article Title: Clinical characteristics and half-year outcomes of 53 children with severe adenovirus pneumonia complicated with encephalitis or encephalopathy

Article References: Zeng, L., Wei, J., Liu, E., Li, Q., & Zang, N. (2026). Clinical characteristics and half-year outcomes of 53 children with severe adenovirus pneumonia complicated with encephalitis or encephalopathy. BMC Pediatrics. https://doi.org/10.1186/s12887-026-07747-w

Image Credits: AI Generated

DOI: 10.1186/s12887-026-07747-w

Keywords: adenovirus, pediatric pneumonia, encephalitis, encephalopathy, bronchiolitis obliterans, mechanical ventilation, retrospective cohort, child health, Clinical, characteristics, half-year, outcomes