Case-control study of the epidemiological and clinical features of human adenovirus 55 and human adenovirus 7 infection in children with acute lower respiratory tract infections in Beijing, China, 2008-2013

Higher affinities of fibers with cell receptors increase the infection capacity and virulence of human adenovirus type 7 and type 55 compared to type 3

IMPORTANCE

HAdV-3, -7, and -55 are the predominant types causing acute respiratory disease outbreaks and can lead to severe and fatal pneumonia in children and adults. In recent years, emerging or re-emerging strains of HAdV-7 and HAdV-55 have caused multiple outbreaks globally in both civilian and military populations, drawing increased attention. Clinical studies have reported that HAdV-7 and HAdV-55 cause more severe pneumonia than HAdV-3. This study aimed to investigate the mechanisms explaining the higher severity of HAdV-7 and HAdV-55 infection compared to HAdV-3 infection. Our findings provided evidence linking the receptor-binding protein fiber to stronger infectivity of the strains mentioned above by comparing several fiber-chimeric or fiber-replaced adenoviruses. Our study improves our understanding of adenovirus infection and highlights potential implications, including in novel vector and vaccine development.

Generation of Human Embryonic Stem Cell-Derived Lung Organoids for Modeling Infection and Replication Differences between Human Adenovirus Types 3 and 55 and Evaluating Potential Antiviral Drugs

Human adenoviruses type 3 (HAdV-3) and type 55 (HAdV-55) are frequently encountered, highly contagious respiratory pathogens with high morbidity rate. In contrast to HAdV-3, one of the most predominant types in children, HAdV-55 is a reemergent pathogen associated with more severe community-acquired pneumonia (CAP) in adults, especially in military camps. However, the infectivity and pathogenicity differences between these viruses remain unknown as in vivo models are not available. Here, we report a novel system utilizing human embryonic stem cells-derived 3-dimensional airway organoids (hAWOs) and alveolar organoids (hALOs) to investigate these two viruses. Firstly, HAdV-55 replicated more robustly than HAdV-3. Secondly, cell tropism analysis in hAWOs and hALOs by immunofluorescence staining revealed that HAdV-55 infected more airway and alveolar stem cells (basal and AT2 cells) than HAdV-3, which may lead to impairment of self-renewal functions post-injury and the loss of cell differentiation in lungs. Additionally, the viral life cycles of HAdV-3 and -55 in organoids were also observed using Transmission Electron Microscopy. This study presents a useful pair of lung organoids for modeling infection and replication differences between respiratory pathogens, illustrating that HAdV-55 has relatively higher replication efficiency and more specific cell tropism in human lung organoids than HAdV-3, which may result in relatively higher pathogenicity and virulence of HAdV-55 in human lungs. The model system is also suitable for evaluating potential antiviral drugs, as demonstrated with cidofovir. IMPORTANCE Human adenovirus (HAdV) infections are a major threat worldwide. HAdV-3 is one of the most predominant respiratory pathogen types found in children. Many clinical studies have reported that HAdV-3 causes less severe disease. In contrast, HAdV-55, a reemergent acute respiratory disease pathogen, is associated with severe community-acquired pneumonia in adults. Currently, no ideal in vivo models are available for studying HAdVs. Therefore, the mechanism of infectivity and pathogenicity differences between human adenoviruses remain unknown. In this study, a useful pair of 3-dimensional (3D) airway organoids (hAWOs) and alveolar organoids (hALOs) were developed to serve as a model. The life cycles of HAdV-3 and HAdV-55 in these human lung organoids were documented for the first time. These 3D organoids harbor different cell types, which are similar to the ones found in humans. This allows for the study of the natural target cells for infection. The finding of differences in replication efficiency and cell tropism between HAdV-55 and -3 may provide insights into the mechanism of clinical pathogenicity differences between these two important HAdV types. Additionally, this study provides a viable and effective in vitro tool for evaluating potential anti-adenoviral treatments.

Identification of functional pathways and potential genes associated with interferon signaling during human adenovirus type 7 infection by weighted gene coexpression network analysis

Human adenovirus type 7 (HAdV-7) can cause severe pneumonia and complications in children. However, the mechanism of pathogenesis and the genes involved remain largely unknown. We collected HAdV-7-infected and mock-infected A549 cells at 24, 48, and 72 hours postinfection (hpi) for RNA sequencing (RNA-Seq) and identified potential genes and functional pathways associated with HAdV-7 infection using weighted gene coexpression network analysis (WGCNA). Based on bioinformatics analysis, 12 coexpression modules were constructed by WGCNA, with the blue, tan, and brown modules significantly positively correlated with adenovirus infection at 24, 48, and 72 hpi, respectively. Functional enrichment analysis indicated that the blue module was mainly enriched in DNA replication and viral processes, the tan module was largely enriched in metabolic pathways and regulation of superoxide radical removal, and the brown module was predominantly enriched in regulation of cell death. qPCR was used to determine transcript abundance of some identified hub genes, and the results were consistent with those from RNA-Seq. Comprehensively analyzing hub genes and differentially expressed genes in the GSE68004 dataset, we identified SOCS3, OASL, ISG15, and IFIT1 as potential candidate genes for use as biomarkers or drug targets in HAdV-7 infection. We propose a multi-target inhibition of the interferon signaling mechanism to explain the association of HAdV-7 infection with the severity of clinical consequences. This study has allowed us to construct a framework of coexpression gene modules in A549 cells infected with HAdV-7, thus providing a basis for identifying potential genes and pathways involved in adenovirus infection and for investigating the pathogenesis of adenovirus-associated diseases.

Construction and analysis of a nomogram prediction model for post-infectious bronchiolitis obliterans in children with adenovirus pneumonia after invasive mechanical ventilation

BACKGROUND

Post-infectious bronchiolitis obliterans (PIBO) is the most common sequelae in children with adenovirus pneumonia (ADVP). However, there are few studies on the risk factors for PIBO occurrence. This study aims to investigate the risk factors for PIBO in pediatric patients with severe ADVP, especially after invasive mechanical ventilation (IMV), as well as to build a nomogram prediction model.

METHODS

The clinical data, laboratory and imaging features, and treatment of 863 children with ADVP under 3 years old who were admitted to our hospital from January to December 2019 were retrospectively analyzed. Among them, 66 children with severe ADVP received IMV treatment. The situation and the influencing factors of PIBO in children with severe ADVP were explored, and a nomogram prediction model was constructed.

RESULTS

Among the 863 cases of ADVP, 46 cases (5.33%) developed PIBO. Duration of fever, IMV, complications, and neutrophil percentage were independent risk factors for PIBO in children with ADVP. Among the 66 patients with ADVP who underwent IMV, 33 patients (50.0%) developed PIBO. Gender, duration of fever, adenovirus (ADV) load, and mixed fungal coinfections were independent risk factors for PIBO. In the nomogram prediction model analysis, the area under the curve (AUC) was 0.857; in addition, Hosmer‒Lemeshow (H-L) detection reflected good alignment (χ2 = 68.75, P < 0.01).

CONCLUSIONS

A nomogram prediction model, which can be utilized to predict PIBO occurrence in pediatric patients with ADVP after IMV at an early time period, was successfully built.

An Old Acquaintance: Could Adenoviruses Be Our Next Pandemic Threat?

Human adenoviruses (HAdV) are one of the most important pathogens detected in acute respiratory diseases in pediatrics and immunocompromised patients. In 1953, Wallace Rowe described it for the first time in oropharyngeal lymphatic tissue. To date, more than 110 types of HAdV have been described, with different cellular tropisms. They can cause respiratory and gastrointestinal symptoms, even urinary tract inflammation, although most infections are asymptomatic. However, there is a population at risk that can develop serious and even lethal conditions. These viruses have a double-stranded DNA genome, 25-48 kbp, 90 nm in diameter, without a mantle, are stable in the environment, and resistant to fat-soluble detergents. Currently the diagnosis is made with lateral flow immunochromatography or molecular biology through a polymerase chain reaction. This review aimed to highlight the HAdV variability and the pandemic potential that a HAdV3 and 7 recombinant could have considering the aggressive outbreaks produced in health facilities. Herein, we described the characteristics of HAdV, from the infection to treatment, vaccine development, and the evaluation of the social determinants of health associated with HAdV, suggesting the necessary measures for future sanitary control to prevent disasters such as the SARS-CoV-2 pandemic, with an emphasis on the use of recombinant AdV vaccines to control other potential pandemics.

Study on the Anti-Adenovirus Mechanism of Sargassum fusiforme

Human adenovirus (HAdV) has a worldwide distribution and remains a major pathogen that leads to infections of the respiratory tract. No specific treatments or vaccines are yet available for HAdV infection. Sargassum fusiforme, an edible seaweed, has attracted a lot of attention for its various bioactivities. S. fusiforme has been reported to exhibit antiviral activity. However, research studies about its anti-HAdV activity are few. In this research, we found that S. fusiforme had low cytotoxicity and possessed anti-human adenovirus type 7 (HAdV7) activity in vitro, and the most effective ingredient was alginate. The time of addition assay demonstrated inhibitory effects that were observed in all life stages of the virus. In addition, we observed that the antiviral activity of alginate against HAdV7 infection might be closely related to the endoplasmic reticulum stress (ERS) pathway. Taken together, these results suggest that S. fusiforme extracts have potential application in the prevention and treatment of HAdV infection.

Severe pneumonia caused by human adenovirus type 55 in children

BACKGROUND

Emerging human adenovirus type 55 (HAdV-55) causes fatal pneumonia in adults. There is a lack of studies on severe pneumonia caused by HAdV-55 in children.

METHODS

We conducted a retrospective review of pediatric patients hospitalized at Guangzhou Women and Children's Medical Center with severe pneumonia from 2013 to 2020 who had human adenovirus (HAdV) detected in throat samples or bronchoalveolar lavage fluid using RT-PCR. The presence of HAdV-55 was determined by PCR amplification of the hypervariable regions of the hexon gene. Demographic, clinical, etiological, and outcome data were collected and analyzed.

RESULTS

Over the eight-year period, HAdV-55 was detected in three severe and six critical pediatric pneumonia patients. None of the patients had any underlying diseases, and had a median age of 18 months (range, 6-108 months). The male to female ratio was 2:1. All patients presented with fever and cough, and three patients presented with wheezing and diarrhea. Six patients had coinfections with other respiratory pathogens, such as bacteria, Mycoplasma pneumoniae and fungi. Three critical patients developed plastic bronchitis (PB). The median lengths of invasive mechanical ventilation and hospital stay of the critical patients were 10 (8, 28.75) days and 25 (13, 32.25) days, respectively. Three critical patients died, although two of them received extracorporeal membrane oxygenation (ECMO) and blood purification. Three surviving patients developed post-infectious bronchiolitis obliterans (PIBO) at the follow-up.

CONCLUSIONS

HAdV-55 can cause fatal pneumonia in children, and shows a high rate of co-infection with other respiratory pathogens and a poorer prognosis combined with PB. Thus, HAdV-55 may be an important subtype in patients with HAdV-induced pneumonia who develop PIBO.

Comparative analyses of clinical features reveal the severity of human adenovirus type 55 and type 7 in acute respiratory tract infections

Introduction. Human adenovirus (HAdV) is an important pathogen in acute respiratory tract infections (ARTIs) and HAdV genotypes are associated with disease severity.Hypothesis. Comparative analyses of clinical features could reveal the severity of different HAdV genotypes in ARTIs.Aim. This study aimed to investigate the molecular epidemiology of HAdV infections and explore the correlations between clinical features and HAdV genotypes.Methodology. A retrospective study was conducted on ARTIs at Beijing Chao-Yang Hospital during the period 2011-2016. A standardized data form was used to record the clinical information. HAdV was detected by FQ-PCR from respiratory specimens, and genotypes were determined by entire hexon gene sequencing.Results. A total of 8044 samples were collected, of which 296 (3.7 %) were HAdV-positive. Patients ≤44 years old were more likely to be positive for HAdV. There were three peak periods of adenoviral infections, with detection rates of 13.03, 9.39 and 10.38 %, respectively. Six HAdV genotypes (HAdV-55, -7, -3, -14, -50, -2) were identified, with HAdV-55 and HAdV-7 being the most prevalent (50.6 and 21.5 %). Compared with HAdV-7 and other types, patients infected with HAdV-55 had a longer duration of fever (P=0.0428). Infections with HAdV-55 and HAdV-7 were more severe compared to those caused by other types, with higher rates of oxygen therapy and mechanical ventilation (P=0.0172 and P=0.0144). All five deaths were caused by HAdV-55.Conclusion. This study describes the epidemiological characteristics of HAdV infections in North China, revealing the higher severity of HAdV-55 and HAdV-7 in ARTIs. Thus, strengthened surveillance of HAdV genotypes is warranted.

Development of Rapid and Visual Nucleic Acid Detection Methods towards Four Serotypes of Human Adenovirus Species B Based on RPA-LF Test

Objectives

Human adenoviruses (HAdV) are classified as 7 HAdV species, and some serotypes in species B like HAdV 3, HAdV 7, HAdV 21, and HAdV 55 caused severe symptoms, even fatalities. Patients may be misdiagnosed and inadequately treated without reliable and practical methods for HAdV serotyping. Developing rapid, sensitive, and specific diagnostic methods for HAdV is critical.

Methods

Detection methods were established based on a recombinase polymerase amplification (RPA) assay and lateral flow (LF) test. Specific target sequence was screened, targeting which, primers and probes were designed, synthesized, and screened for establishing assay with high amplification efficiency. Primer or probe concentrations and amplification time were optimized. Detection limit, sensitivity, and specificity were evaluated. Results and Conclusions. Simple, sensitive, and specific RPA-LF methods for detection of four serotypes of HAdV together or separately were established, which had detection limits of 10 to 280 copies/reaction comparable to real-time PCR without recognizing other pathogens. The sensitivity and specificity were >92% and >98%, respectively, evaluated by limited clinical samples. The detection can be completed in 25 min without requirement of any instrument except a constant temperature equipment, showing superior detection performance and promising for a wide use in the field and resource-limited area.

Application of Human Adenovirus Genotyping by Phylogenetic Analysis in an Outbreak to Identify Nosocomial Infection

Nosocomial infections are common in pediatric patients and can be fatal in infants and immunocompromised patients. In September 2018, a high positive rate of human adenovirus HAdV was occurred among hospitalized children in the Children's Hospital Affiliated to the Capital Institute of Paediatrics in Beijing. To investigate whether this outbreak of HAdV was related to nosocomial infections or the result of community infections, we collected respiratory specimens from patients with acute respiratory infections in a respiratory ward during June to December 2018, and screened for respiratory viruses. Among 1,840 cases included, 95 (5.2%, 95/1840) were positive for HAdV and 81 were genotyped based on phylogenetic analysis, including seven as HAdV-1 (8.6%), 30 HAdV-3 (37.0%), two HAdV-6 (2.5%), and 42 HAdV-7 (51.9%). More HAdV-positive samples were collected in August (4.7%, 12/255), September (15.0%, 41/274) and October (6.9%, 17/247), with a peak in September 2018. By combining the results of HAdV phylogenetic analysis with clinical data of patients, there were 77 cases (4.2%, 77/1840; 81.1%, 77/95) excluded from nosocomial infections, eight cases representing possible infections transmitted by visitors or attending parents, three cases without sequences that might have been due to infection transmitted by roommates positive for HAdV, one case of a roommate without an HAdV sequence, and six cases that shared highly homologous sequences with those of their roommates, for which nosocomial infections might be considered. In conclusion, genotyping of HAdVs based on phylogenetic analysis combined with clinical information provides a powerful method to distinguish nosocomial infections from community acquired infection, especially when tracing the origins of nosocomial infections.

Patient hematology during hospitalization for viral pneumonia caused by SARS-CoV-2 and non-SARS-CoV-2 agents: a retrospective study

Background

Hematological comparison of coronavirus disease (COVID-19) and other viral pneumonias can provide insights into COVID-19 treatment.

Methods

In this retrospective case–control single-center study, we compared the data of 126 patients with viral pneumonia during different outbreaks [severe acute respiratory syndrome (SARS) in 2003, influenza A (H1N1) in 2009, human adenovirus type 7 in 2018, and COVID-19 in 2020].

Results

One of the COVID-19 characteristics was a continuous decline in the hemoglobin level. The neutrophil count was related to the aggravation of COVID-19 and SARS. Thrombocytopenia occurred in patients with SARS and severe COVID-19 even at the recovery stage. Lymphocytes were related to the entire course of adenovirus infection, recovery of COVID-19, and disease development of SARS.

Conclusions

Dynamic changes in hematological counts could provide a reference for the pathogenesis and prognosis of pneumonia caused by respiratory viruses in clinics.

Chinese tree shrew: a permissive model for in vitro and in vivo replication of human adenovirus species B

Human adenovirus (HAdV) species B can cause severe acute respiratory diseases. However, the researches to combat this infection have been hampered by the lack of an animal model permissive to the virus. Here, we report in vitro and in vivo HAdV species B infections of tree shrews, the closest relative of primates. HAdV-3, -7, -14, and -55 efficiently replicated in primary cell cultures. After intranasal inoculation of tree shrews with HAdV-55, the viral replication in the oropharyngeal region remained high until day 5 post-infection and was still detected until day 12. HAdV-55 in the lung or turbinate bone tissues reached the highest levels between days 3 and 5 post-infection, which indicated viral replication in the upper and lower respiratory tracts. HAdV-55 infection caused severe interstitial pneumonia in the animal. IL-8, IL-10, IL-17A, and IFN-γ expression in the peripheral blood mononuclear cells from infected animals was up-regulated. The pre-vaccination with HAdV-55 cleared the virus faster in the respiratory tract, mitigated lung pathological changes. Finally, HAdV-55 infection was propagated among tree shrews. Our study demonstrated that the tree shrew is a permissive animal model for HAdV species B infection and may serve as a valuable platform for testing multiple anti-viral treatments.

The Epidemiology, Molecular, and Clinical of Human Adenoviruses in Children Hospitalized With Acute Respiratory Infections

Introduction

Human adenovirus (HAdV) is a common pathogen in children with acute respiratory infections (ARIs). The aim was to describe the epidemiology, molecular, and clinical characteristics of HAdV among children hospitalized with ARIs in Wenzhou in southeastern China.

Methodology

From January 2018 to December 2019, nasopharyngeal swab or sputum specimens were prospectively collected from hospitalized children with ARIs. HAdV was detected using direct immunofluorescence. We used a multiplex PCR assay combined with capillary electrophoresis targeting the hexon gene’s hypervariable region to identify HAdV types 1, 2, 3, 4, 5, 7, 14, 21, 37, 40, 41, and 55. We analyzed the epidemiological, molecular, and clinical data according to the HAdV type.

Results

HAdVs were detected in 1,059 (3.5%) of the total of 30,543 children tested. A total of 947 cases with monotype HAdV identified by the PCR assay were included in the analysis. HAdV-3 (415/947, 43.8%), HAdV-7 (318/947, 33.6%), HAdV-2 (108/947, 11.4%), and HAdV-1 (70/947, 7.4%) were the predominant types. Of the 550 (58.1%) cases detected from December 2018 to August 2019, HAdV-3, and HAdV-7 were the main types. The main diagnoses included 358 cases of pneumonia, 232 cases of tonsillitis, 198 cases of bronchitis, and 159 cases of upper respiratory tract infection (URTI). Among children with pneumonia the main types were HAdV-7 (51.1%), HAdV-3 (36.9%), and HAdV-1 (2.2%). Among children with bronchitis, the main types were HAdV-3 (48.0%), HAdV-7 (28.3%), and HAdV-2 (10.6%). Among children with URTIs, the main types were HAdV-3 (49.7%), HAdV-7 (22.6%), and HAdV-2 (13.2%). Among children with tonsillitis, the main types were HAdV-3 (47.4%), HAdV-2 (22.4%), and HAdV-7 (18.5%). In total, 101 (55.2%) patients required supplemental oxygen, 15 (8.2%) required critical care, and 1 child (0.5%) with HAdV-7 pneumonia died.

Conclusion

HAdV-3 -7, -2, and -1 were the predominant types identified in hospitalized children with ARIs in Wenzhou. From December 2018 to August 2019, there were outbreaks of HAdV-3 and -7. There were significant differences in HAdV types among children with pneumonia, tonsillitis, bronchitis, and URTI. HAdV-7 can cause more severe pneumonia in children than HAdV-3.

Complete Genome Sequences of Two Human Adenovirus Type 55 Isolates from South Korea and the United States

Here, we report two complete genome sequences of human adenovirus 55 (HAdV-55) isolates, from a patient in Pennsylvania in 2006 and a U.S. military member in South Korea in 2019. The findings demonstrate the continued global transmission of HAdV-55 viruses in both military and civilian populations.

Here, we report two complete genome sequences of human adenovirus 55 (HAdV-55) isolates, from a patient in Pennsylvania in 2006 and a U.S. military member in South Korea in 2019. The findings demonstrate the continued global transmission of HAdV-55 viruses in both military and civilian populations.

Clinical Signs, Prevention and Treatment of Viral Infections in Infants

Certain infectious diseases are common in infants than any other age groups and are associated with morbidities in childhood and adulthood, and even mortality in severe cases. Environment, epidemic and maternal immunity are the main causes of these infections. Early diagnosis using molecular methods and treatment is therefore important to prevent future complications. Vaccines are recommended during infancy and childhood to prevent these infections. This review highlights some of the most commonly reported viral infections in children, their clinical signs, prevention and treatment.

Epidemiology and Genetic Variabilities of Human Adenovirus Type 55 Reveal Relative Genome Stability Across Time and Geographic Space in China

After the first outbreak in China in 2006, human adenovirus type 55 (HAdV-B55) has become a common pathogen causing life threatening pneumonia in northern China. However, HAdV-B55 infection has been rarely reported in southern China. Here, we collected throat swabs from 3,192 hospitalized children with acute respiratory disease (ARD) from May 2017 to April 2019 in Guangzhou, southern China, tested them for HAdV-B55 infection. Only one of 1,399 patients from May 2017 to April 2018 was HAdV-B55 positive; HAdV-B55 infections significantly increased with 10 of 1,792 patients testing positive since May 2018. HAdV-B55-267, isolated from a case of death, was sequenced for whole genomic analysis. Three other strains, HAdV-B55-Y16, -TY12, and -TY26, isolated earlier in patients from Shanxi, northern China, were also sequenced and analyzed. The four HAdV-B55 strains formed similar plaques, grew to similar titers, and resulted in similar typical cell pathogenic effects. HAdV-B55-267 formed a subclade with the prototype strain QS-DLL; strains HAdV-B55-Y16, -TY12, and -TY26 were closely related to strain QZ01. HAdV-B55 could be divided into two subtypes (HAdV-B55-a and -b) according to the presence or absence of the insertion of "CCATATCCGTGTT"; all strains isolated from China except for strain BJ01 belong to subtype b. HAdV-B55-267 had only one non-synonymous substitution comparing with strain QS-DLL, and all HAdV-B55 strains had highly conserved capsid proteins and few non-synonymous substitutions. This study suggests that HAdV-B55 is an important pathogen associated with ARD in Guangzhou since 2018, exhibiting the relative genome stability across time and geographic space in China.

Cross-infection of adenovirus among medical staff: A warning from the intensive care unit in a tertiary care teaching hospital in China

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Human adenovirus-55 in a single patient had strong transmission potential in ICU.

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This infectious event involved more than 20 medical staff members in adult ICU.

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Contact with patient, lack of hand hygiene or gloving adherence, were risk factors.

Rationale

In 2019, a small HAdV55-associated outbreak of adenovirus infection occurred among the intensive care unit (ICU) staff in Xiangya Hospital of Central South University in Hunan Province, China, during the treatment of a patient.

Objective

To investigate the characteristics of a nosocomial adenovirus outbreak in an ICU.

Methods

We evaluated all the patients treated and the medical staff working in the ICU from August 1 to September 4, 2019. We further performed an epidemiological and molecular analysis for this outbreak from patient to healthcare workers and between healthcare workers. After the outbreak, we adopted exposure prevention and droplet prevention measures based on standard precautions.

Measurements and main results

Between August 1 and August 27, 2019, 27 cases of human adenovirus cross-infection were reported in our institution. Among the cases, eleven were doctors (41%), eleven were nurses (41%), three were respiratory therapists (11%), and two were caregivers (7%). The attack rate was 28.4%, and the fatality rate was 0. The results showed that contact with the index case, lack of hand hygiene or gloving adherence were risk factors for infection after adenovirus exposure. After taking specific precautions, no new cases of infection have appeared since August 27.

Conclusions

Our results show that HAdV55 in a single patient had strong transmission potential in an intensive care unit with adequate facilities and standardized operation. We provide convincing evidence indicating that attention could be highlighted on the role of standard and specific precautions for controlling the spread of adenovirus in ICUs.

Severe Adenovirus Pneumonia Requiring Extracorporeal Membrane Oxygenation Support in Immunocompetent Children

Objective: To highlight severe adenovirus pneumonia in immunocompetent patients by analysis of severe adenovirus pneumonia associated with acute respiratory distress syndrome in whom extracorporeal membrane oxygenation (ECMO) support is required. Methods:Pediatric patients with adenovirus pneumonia and ECMO supports in our hospital from February 2018 to May 2019 were retrospectively analyzed, and having 100 common adenovirus pneumonia children as a control. Results:A total of 8 patients, including 4 boys (50.0%), were enrolled. They were previously immunocompetent with a median age of 31 months. They were admitted as persistent fever and cough for more than one week. Median time prior to development of respiratory failure requiring intubation and invasive mechanical ventilation was 5 days. Venoarterial ECMO support as rescue ventilation was instituted after a median time of 24.5 h of conventional mechanical ventilator support. The median duration on ECMO support was 9 days and mechanical ventilation was 14 days, respectively. Six patients (75%) were recovered and 2 (25%) died. Median length of stay in ICU and hospital were 27.5 days and 47.5 days, respectively. Conclusion:The promising outcomes of our cases suggested that ECMO support for rescue ventilation may be considered when symptoms deteriorated in adenovirus pneumonia patients, and may improve outcome. However, sequelae of adenovirus pneumonia and ECMO-related complications should also be taken into account.

[Research progress on early identification of severe adenovirus pneumonia in children]

Severe adenovirus pneumonia has a high mortality and incidence of sequelae. Fever and cough are the main symptoms of children's severe adenovirus pneumonia, but such clinical manifestations are lack of specificity. For children with persistent high fever who are in the epidemic age and season, the adenovirus etiology detection, blood routine, cytokines, T cell subsets and imaging examinations are suggested. Children with early manifestations of infiltration of lung segment and lobar parenchyma, obvious emphysema, interstitial pneumonia or a large amount of pleural effusion should be alerted to have severe adenovirus pneumonia. This article reviews the epidemiological characteristics and risk factors of adenovirus pneumonia in different seasons, regions and serology, and the laboratory findings and imaging features of severe adenovirus pneumonia, which would be helpful for the early identification of the disease.