Clinical manifestations of adenovirus infection

In the last issue, we introduced the viral characteristics and epidemiology of adenovirus. In this issue, we will introduce the clinical manifestations of adenovirus infection.

Adenovirus, also known as human adenovirus (HAdV), infects different organs or systems and causes diseases in corresponding parts. For example, HAdV infection of the respiratory tract can cause upper respiratory tract infection, pneumonia, pharyngeal conjunctival fever, etc.; infection of the digestive tract can cause gastroenteritis, hepatitis, etc.; in addition, it can also cause some rare diseases, such as cystitis, nephritis and meningoencephalitis. Today we will mainly introduce the clinical manifestations of the respiratory system and digestive system after HAdV infection.

Respiratory manifestations associated with HAdV infection

HAdV infection of the respiratory tract may be a latent infection, that is, no obvious clinical symptoms. Symptomatic infection of the upper respiratory tract is more common, and a few can develop severe pneumonia and even death.

latent infection

1?There are no obvious clinical symptoms, but it is contagious to a certain extent.

Acute respiratory infection

The most common form of HAdV infection.

2 The symptoms of HAdV are similar to other respiratory viral infections, mainly manifested as fever, and may be accompanied by other manifestations such as cough and sore throat. However, it should be noted that after HAdV infection, there is generally a persistent high fever with a body temperature of over 39°C. A small number of children may have symptoms such as headache and dizziness. The general course of disease is 1 to 14 days (average 5 to 7 days).

Pharyngeal conjunctival fever is a special type of upper respiratory tract infection, mainly caused by HAdV-B and HAdV-E infection. The prominent symptoms are fever and conjunctival hyperemia, less ocular secretions, higher degree of fever, longer course of disease, and generally lasting 1 ~2 weeks. In childcare institutions or homes, and public places such as swimming pools, outbreaks of infection may occur.

Because children's immune systems are immature, they are more likely to develop lower respiratory tract infections after infection. HAdV pneumonia is one of the most serious types of infant pneumonia, with a fatality rate of 5-10%. The onset is rapid after infection, mostly manifested as persistent high fever, severe cough, and in severe cases, wheezing and difficulty breathing. Inconsistent with the severe clinical symptoms, the patient's pulmonary signs appeared relatively late, and the chest imaging examination was consistent with the clinical manifestations. More emphysema, more large lesions, more fusion lesions; less round lesions, less bullae, and less pleural effusion. Relatively speaking, after HAdV infection in the lungs, the absorption of the lesions is slow, and the recovery time is longer, which takes several weeks or even months. A small number of critically ill patients may also experience persistent dyspnea, shock, disseminated intravascular coagulation, etc., and even lead to death.

Digestive system manifestations associated with HAdV infection

Digestive system involvement is one of the most common extrapulmonary manifestations of HAdV infection.

Gastrointestinal manifestations associated with HAdV infection

1?HAdV is also one of the common pathogens of viral diarrheal diseases, which is most common in children under the age of 5. In different studies, the detection rate of HAdV in stool samples of children with diarrheal diseases ranges from 4% to 32%. The symptoms of HAdV gastroenteritis have no obvious specificity, but compared with rotavirus enteritis, there is no obvious seasonality. Fever, vomiting, abdominal pain, etc.

HAdV infection associated hepatitis

2?In recent years, some scholars have speculated that HAdV infection may be the "culprit" for the severe acute hepatitis of unknown cause in children caused by the new crown epidemic, but there is no direct evidence that the two are necessarily related.

Existing research data shows that HAdV infection-related hepatitis mainly occurs in immunocompromised people, such as children after organ transplantation or hematopoietic stem cell transplantation. The clinical symptoms are nonspecific, and fever is the most common symptom. Other manifestations include general malaise. Symptoms, diarrhea and jaundice.

References

1. Expert group for the preparation and review of technical guidelines for the prevention and control of human adenovirus respiratory tract infections. Technical guidelines for the prevention and control of human adenovirus respiratory tract infections (2019 edition) [J]. Chinese Journal of Preventive Medicine, 2019,53(11):1088-1093. DOI :10.3760/cma.j.issn.0253-9624.2019.11.004.

2. Zhou Ronghua. Extrapulmonary manifestations and pathogenesis of adenovirus infection in children [J]. International Journal of Pediatrics, 2022, 49(4): 245-248. DOI: 10.3760/cma.j.issn.1673-4408.2022.04.007 .

The Bioperfectus Enteric Adenovirus Real Time PCR Kit is an in vitro diagnostic test, based on real-time PCR technology, for the detection of DNA from the Enteric Adenovirus. Specimens can be obtained from human stool.