Clinical Characteristics of 204 Children With Human Adenovirus Type 7 Pneumonia Identified by Whole Genome Sequencing in Liuzhou, China

Background: Clinical knowledge of human adenovirus type 7 (HAdV-7) pneumonia in children remains limited. Moreover, predictors for disease severity are largely unknown. Methods: This is a retrospective study of children hospitalized at Liuzhou Maternal and Child Health Hospital, China, with HAdV-7 pneumonia in 2018-2019. Demographics, clinical characteristics, laboratory results, and imaging data were collected. HAdV-7 was identified in plasma using whole genome sequencing, which yielded quantitative HAdV-7 sequence numbers. Results: There were 204 children; 145 (71%) were <2 years of age. There were 68 children with severe pneumonia (SP) and 136 with nonsevere pneumonia (NSP). Up to 43% in SP group with respiratory failure (SP-RF) were <12 months of age. Median duration of fever before hospitalization was shorter in NSP group than SP groups (P < 0.01). Fourteen (6.9%) underwent mechanical ventilation. There was a significant difference in mean plasma HAdV-7 sequence numbers among SP-RF, SP without respiratory failure (SP-NRF), and NSP groups (2485 +/- 165, 2034 +/- 124, and 286 +/- 35, respectively) (P < 0.01). In a logistic regression analysis, we found that elevated plasma HAdV-7 sequence numbers significantly increased the risk of severe HAdV-7 pneumonia (OR 1.80, 95% confidence interval: 1.59-2.60, P < 0.01) after adjusting for age, fever duration, platelet counts, and serum lactate dehydrogenase levels. Conclusions: Over two-thirds of children hospitalized with HAdV-7 pneumonia were <2 years of age. Approximately 40% of those with SP associated with respiratory failure were <12 months of age. Those with SP exhibited higher plasma HAdV-7 sequence numbers. Thus, plasma HAdV-7 sequence numbers have a potential in predicting severity of HAdV-7 pneumonia in children.