A study of some viral pathogens in infants and children with lowe respiratory tract infection and attending the intensive care unit

ABSTRACT

Acute lower respiratory tract infections are the most common illness in pediatrics. A great variety of viruses especially RSV can cause bronchopneumonia and bronchiolitis in infants and children. This work aimed to evaluate some viral pathogens in pneumonia and bronchiolitis in infants and children admitted to the ICU. This study included 142 patients, 70 suffered bronchopneumonia and 72 suffered bronchiolitis admitted to the ICU in Assiut Pediatric University Hospital, Egypt. The study was done from November 2002 to February 2003 and from the period of November 2003 to February 2004. Clinical evaluation, chest x-ray, complete blood count and arterial blood gases as well as endotracheal suction for collection of the samples for viral study and bacterial cultures were done. Regarding viral tissue culture 66 patients were positive to the studied viruses [26 with bronchopneumonia and 40 with bronchiolitis] with male predominance [43 males with 65.1%]. Out of the 66, 48 were below age of 12 months, 12 were below age of 24 months and 6 were below 36 months. Respiratory Synsytial virus [RSV] was found in 32 cases [484%], influenza A was in 12 [18.1%], Parainfluenza 3 in 18[27.2%], Parainfluenza I in 4 [6%] and adenovirus in 4 [6%]. It was noticed that there were positive bacterial cultures in 27 cases and also mixed viral types. Malnutrition especially the severe type was concomitant with viral infection specially RSV, As regards the blood gases and respiratory rate it was found that cases with bronchiolitis showed significant differences than those of bronchopneumonia where bronchiolitis was more severe than bronchopneumonia. There were 76 cases negative to the studied viruses 44 were bronchopneumonia and 32 were bronchiolitis. Bacterial cultures were positive in 25 patients. Analysis of the blood count showed leucocytosis in the cases as a whole with significant higher levels in the cases with positive bacterial cultures than those with viral infection only. Lymphocytes were significantly higher in the cases with positive viral cultures than those negative to these cultures and eosinophils were significantly higher in the cases negative to the studied viruses and also showed negative bacterial cultures that the cause could be due to allergic conditions. As regards the outcome of the cases that were positive to the studied viruses 29 died [43.9%], 20 of them were due to RSV infection. It is concluded that RSV is the commonest cause of viral lower respiratory tract infection in infants and children. Mixed viral and bacterial infection is not uncommon which is strongly concomitant with the immunocompromised patients' especially malnourished cases. So the use of immunostimulants in addition to antimicrobial and antiviral drugs may be beneficial in such cases