Clinical features of HAdV-55 in children with respiratory tract infections: a retrospective case series and literature review

Abstract

Background: Human adenovirus type 55 (HAdV-55) can lead to acute respiratory diseases, significant morbidity, and mortality in children.

Methods: Hospitalized children diagnosed with HAdV-55 between September 2016 and March 2024 at the Children's Hospital of Chongqing Medical University were retrospectively analyzed. HAdV-55 was detected through polymerase chain reaction and sequencing. Clinical data were collected, including demographic characteristics, clinical manifestations, laboratory findings, imaging results, treatment history, and prognosis. A literature search was conducted using the PubMed database and China National Knowledge Infrastructure from their inception to June 2024. Search terms included "HAdV-55", "HAdV-11a", "adenovirus type 55" and their derivatives. Clinical features were evaluated in conjunction with literature on HAdV-55 infections in children.

Results: Five children with HAdV-55 infection were identified, including one mild, two severe, and two critical. The two critical patients exhibited progressive declines in total blood cell counts, hemoglobin levels and serum albumin levels within a short period. Adenoviral DNA was detected in pleural fluid or serum for them. They received mechanical ventilation, intravenous immunoglobulin, Methylprednisolone, blood transfusions, and antibiotics, while died for acute respiratory distress syndrome (ARDS). The remaining ones recovered and were discharged with good prognosis. A review of 56 cases, including those from this study, revealed that 61.9% (26/42) of infections were classified as severe or critical, with a mortality rate of 16.4% (9/55). Sequelae included bronchiolitis obliterans and bronchiectasis.

Conclusions: The genetic inheritance of HAdV-55 remained stable, with an upward trend of HAdV-55 severe infection among children from 2000 to 2019. Early clinical symptoms of HAdV-55 infection were overlapped with other respiratory viral infections. Rapid declines in blood cell counts, hemoglobin levels and serum albumin, along with dynamic monitoring of viral loads in sterile fluids, may serve as prognostic indicators.

Keywords: ARDS; Children; Clinical features; HAdV-55; Infection.

Fig. 1

Pulmonary imaging of patients 1, 3, 4, and 5. Patient 2 underwent X-ray examinations at an external hospital and no imaging data were acquired

Fig. 2

Evolution information of CQ2403 strain. (A-D) Based on the HAdV-11 QS strain, phylogenetic analysis of CQ2403 strain was performed with the entire penton gene (nt13682 to 15355), hexon gene (nt18232 to 21073), fiber gene (nt30775 to 31752) and whole-genome from 16 viral strains representing seven HAdV groups (A-G). Corresponding subgenus types are indicated in parentheses after respective serotypes. HAdV-3 (AY599834), HAdV-4 (AY594253), HAdV-5 (AY601635), HAdV-7 (AY594255), HAdV-11 (AF532578), HAdV-12 (AC_000005), HAdV-14 (AY803294), HAdV-16 (AY601636), HAdV-21 (AY601633), HAdV-26 (EF153474), HAdV-34 (AY737797), HAdV-35 (AY128640), HAdV-40 (NC_001454), HAdV-50 (AY737798), HAdV-52 (DQ923122), and HAdV-55(FJ643676). A, HAdV-A; B1, HAdV-B1; B2, HAdV-B2; C, HAdV-C; D, HAdV-D; E, HAdV-E; F, HAdV-F; G, HAdV-G. Relative phylogenetic distances were measured from the lowest scales of each phylogenetic tree (0.05)

Fig. 3

Summary of clinical HAdV-55 infections in children. Worldwide (A) and China (B) distributions of HAdV-55 in 56 children. (C) Temporal trends in HAdV-55 infection

Fig. 4

Multiple infections of clinical cases. (A and B) Mono-detection and co-detections patterns of HAdV-55 in all reported cases. (C and D) Types and frequencies of complications in children infected with HAdV-55. (E and G) Comparison of mono-detection and co-detections in relation to survival and died patients with severe HAdV-55 pneumonia. (F and H) Specific pathogens of co-detections between survival and died patients with severe HAdV-55 pneumonia