Respiratory Viruses in Pediatric Necropsies: An Immunohistochemical Study

Abstract

Infections of the respiratory system are responsible for the majority of hospitalizations and deaths in pediatric patients in developing countries. We selected 177 necropsies of pediatric patients who died as a result of serious respiratory infections. The histopathological findings and epidemiological data were reviewed, and lung tissue samples were separated for immunohistochemistry testing. Conventional immunohistochemistry techniques were used to detect viral antigens in formalin-fixed, paraffin-embedded (FF-PE) lung tissue samples using a pool of monoclonal antibodies against respiratory viruses (respiratory syncytial virus, influenza A and B, adenovirus, and parainfluenza 1, 2, and 3 viruses) as primary antibodies. The histopathological findings were classified into bronchopneumonia (BCP) and interstitial pneumonitis (IP) patterns. The immunohistochemistry results were compared with histopathological patterns and epidemiological data. Positive results for viruses were found in 34% and 62.5% of the BCP and IP cases, respectively. Males and infants below 1 year of age were more frequent in the group that had positive results for viruses. Acute enteritis was the main cause of hospitalization and sepsis the most frequent cause of death in this group. A clear seasonal distribution was observed, with the majority of cases occurring in the 2nd and 3rd trimesters (autumn and winter) of each year in the period studied. Immunohistochemistry is an affordable and easy-to-perform method for viral-antigen detection in FF-PE tissue samples. Although BCP is a classic histopathological pattern found in bacterial infections, it is possible that children with serious respiratory infections had concomitant viral and bacterial infections, regardless of their previous immunologic state.

Respiratory Syncytial Virus: From Discovery to Treatment

“…Pneumonia has been considered as virus infection too. Respiratory virus was found isolated in children's necropsies died by severe respiratory diseases (Chong DC et al 2009). …”

Infantile Viral Illnesses

“…Lower respiratory tract infections (LRTI) are a leading indication for hospitalization (2-3 %) in young children. Approximately 90 % of LRTI in children are viral, in contrast to adults, in whom approximately 12 % of community-acquired LRTIs have a viral etiology (Hammond et al 2007 ;Chong et al 2009 ;Welliver 2003 ).…”

“…The most common pathologic viruses in infancy include respiratory syncytial virus (RSV), parainfl uenza virus (PIV), adenovirus (AdV), infl uenza virus (InfV), human metapneumovirus (hMPV), and less so coronavirus (CoV), rhinovirus (RhV), and bocavirus (BoV) (Tregoning and Schwarze 2010 ;Hammond et al 2007 ;Chong et al 2009 ). RSV remains the most prevalent and most severe of the neonatal LRTI's (Coffi n 2005 ; Hammond et al 2007 ;Chong et al 2009 ;Chang et al 2009 ;Fitzgerald 2011 ).…”

“…RSV remains the most prevalent and most severe of the neonatal LRTI's (Coffi n 2005 ; Hammond et al 2007 ;Chong et al 2009 ;Chang et al 2009 ;Fitzgerald 2011 ). Studies indicate that 20-67 % of children less than 1 year of age will be infected by RSV, with infection rates up to 95 % by age 2 years (Tregoning and Schwarze 2010 ;Hammond et al 2007 ;Fitzgerald 2011 ;Johnson et al 2007 ).…”

“…Importantly, PCR for DNA viruses and reverse transcriptase PCR (RT-PCR) for RNA viruses also have allowed identifi cation of viruses which are difficult to culture, such as hMPV and BoV, allowing better delineation of multi-agent respiratory viral infections (Tregoning and Schwarze 2010 ). The most common synchronously occurring respiratory viruses are RSV and RhV (Tregoning and Schwarze 2010 ;Chong et al 2009 ;Garcia et al 2010 ). In the last decade, hMPV, BoV, CoV, and RhV are increasingly recognized as causes of lower respiratory viral infections in children (Hustedt and Vazquez 2010 ).…”