Retrospective study of adenovirus in autopsied pulmonary tissue of pediatric fatal pneumonia in South China

Nested PCR was performed on DNA extracted from autopsied lung tissue from patients who died of severe pneumonia, and the positive nested PCR products were cloned and sequenced. The adenovirus in autopsied pulmonary tissue was also analyzed by immunohistochemistry assay in a blind way.In the 175 autopsied pulmonary tissues, the positive percentage of adenovirus was 9.14% (16/175) and 2.29% (4/175) detected with nested PCR and immunohistochemistry, respectively. There are three cases of adenovirus serotype 3, twelve cases of adenovirus serotype 4 and one case of serotype 41 determined by sequencing of the cloned positive nested PCR products.Adenovirus is an important cause of severe pneumonia, and these data suggest that adenovirus serotype 4 might be an important pathogen responsible for the fatal pneumonia in Guangzhou, South China.Adenoviruses (AdVs) are non-enveloped, double-stranded DNA viruses that vary in size from 70 to 100 nm. They are the common pathogens of respiratory tract, gastrointestinal tract, urethral canal and eye characterized by self-limiting infection[1]. AdVs are endemic in children, and infections usually occur at young age (5 months to 6 years)[2,3]. AdVs can incite continuous and intensive infection with the utilization of a detective or compromised immune system sometimes resulting in lethality[4]. The clinical symptoms of AdVs infection are atypical and variable, including amygdalitis, conjunctivitis, pneumonia, gastroenteritis, hepatitis and hemorrhagic cystitis[2,3,5-9]. Local infections generalize in some cases and then have a mortality rate of up to 60%[2,3,5,7,8,10]. AdVs are the important pathogen of pediatric severe pneumonia, which can cause large-scale epidemics. For example, AdVs pneumonia was the most common pneumonia in Beijing and Shanghai area of China from the 1950s to 1960s characterized by complications, high mortality, but the incidence declined in the late 1980s with some diverging occasionally [11-13]. As reported from Z