[Will chronic nonproductive cough with bronchial hyperresponsiveness be cough variant asthma?].

OBJECTIVE

The clinical characteristics of the patients suffered from chronic nonproductive cough with bronchial hyperresponsiveness were analyzed, so as to evaluate the value of measurement of bronchial responsiveness in diagnosis of cough variant asthma (CVA).

METHOD: 124 patients with chronic nonproductive cough were divided into two groups after the measurement of bronchial responsiveness: cough bronchial hyperresponsiveness positive group (CBH-P, n = 35) and cough bronchial hyperresponsiveness negative group (CBH-N, n = 33). Routine pulmonary function, positive rate of antigen-skin pitting lest, count of blood eosinophil cells, level of blood IgE, positive rate of prednisone test and the number of development of classical asthma in two-year following up were studied.

RESULT: The percentage of FEV1.0 in group CBH-P was significantly lower than in group CBH-N, but antigen-skin pitting test, count of blood eosinophil cells, prednisone test and the number of development of classic asthma in two-year following up were all higher than in the latter group. In group CBH-P, there was no significant difference in positive rate of antigen-skin pitting test, routine pulmonary function, reacting threshold(Dmin) and wheezing threshold (DCW/Dmin) between the patients who developed classic asthma and those who did not.

CONCLUSION

The measurement of bronchial responsiveness is important for the diagnosis of CVA, but it is not the only diagnostic criteria and should be combined with other clinical data.