[Study of the clinical and epidemiological characteristics of respiratory infections caused by adenovirus in a pediatric population (1997-2003)].

BACKGROUND

Infections due to adenoviruses are highly prevalent in pediatric patients. Because the clinical manifestations of the respiratory infections caused by adenoviruses are indistinguishable from those caused by other respiratory viruses, virological methods are required to establish their etiology. We present a retrospective study of the clinical and virological characteristics of patients with isolation of adenovirus in respiratory samples.

METHODS

From 1997 to 2003 we analyzed 5,746 respiratory samples from pediatric patients (< 15 years old), of which 2,122 (36.9 %) were considered positive. The adenoviruses were isolated in the Hep-2 cell line culture by the shell vial method.

RESULTS

Adenovirus was isolated in 100 clinical samples (4.7 % of all positive samples and 1.7 % of all samples studied) in a group of pediatric patients with a mean age of 14 months. The clinical diagnoses of patients were bronchiolitis (61 %), pneumonia (10 %), pertussis-like syndrome (16 %) and asthmatic crisis (11 %). Adenovirus infections mainly presented between December and March. Seventy-two percent of patients had a history of other viral respiratory tract infections and/or bronchial asthma. None of the patients had clinical conjunctivitis and only five patients had diarrhea due to adenoviruses. Seventy percent of the patients received artificial feeding and 30 % were breast-fed. Ninety percent of the patients were hospitalized and treatment mainly consisted of bronchodilator agents and antibiotics.

CONCLUSIONS

Respiratory tract infections caused by adenoviruses mainly affected patients aged less than 14 months, in the first four months of the year, and with clinical manifestations of bronchiolitis or pneumonia without conjunctivitis. Clinically, these infections are difficult to differentiate from other viral respiratory infections.