[The role of respiratory tract viruses in the etiology of obstructive bronchitis in infants].

Out of 524 children with acute respiratory infections in 141 obstructive bronchitis was diagnosed (OZO). Seventy cases could be linked to viral infection. Viral infections tested (influenza virus A, B, parainfluenza typ 1-3, RSV, adenoviruses) were more frequently associated with OZO than other acute respiratory infections of unknown etiology. Majority infections induced by influenza virus A and parainfluenza virus typ 2 were accompanied by OZO symptoms. Of the highest risk of acquiring OZO despite of viral infection participation, were children of 4-12 months of age. OZO associated viral infections prevailed during autumn-winter season, while in spring-summer period undetermined factors were the major cause of OZO. In serum samples of children with OZO, despite of etiology of the disease, higher level of IgE was found than in a group of children without the symptoms. In the case of OZO of unestablished etiology the level of serum IgE was significantly higher than in the cases when viral etiology of the disease was found.