[A study on the relationship between viral infections and asthma in adults]

Abstract

Objective: To study the relationship between viral infections and asthma in adults, and the mechanism that viruses lead asthma.

Methods: The sera from 130 adults of asthma and 20 normal controls are both tested for specific IgG and IgM of RSV, ADV3, ADV7, PIVI, PIVIII and CMV by an indirect ELISA, then the result is compared by chi 2 test. The RSV-IgM positive patients obtained from above and normal controls are both tested for RSV-IgE by the indirect ELISA and for titres of interferon(IFN) by microcytopathic-inhibiting-test, the results are both compared by t test.

Results: Almost all the patients have one or more viral infections, the highest infective rate is RSV, the total positive rates of IgG and IgM are 78%, compared with controls, chi 2 = 47.6, P < 0.00001. The acute infection can enhance asthma. From 17 patients of RSV-IgM positive, the sera titres of RSV-IgE are higher than controls apparently (t = 2.45, P < 0.05), IFN levels are lower than controls significantly (t = 2.83, P < 0.01).

Conclusions: That asthma breaks out or becomes heavier in adults has close relationship with respiratory viruses infections, especially with RSV. Its mechanism is relative to the immune injury of viruses, hypersensitivity-type I and lower titres of immune regulating factor of IFN.