PURPOSE: There are various etiologies causing bronchiectasis, but the cases without definite causes account for a quite high proportion. It is also uncertain that immunoglobulin G subclass deficiency (IgGSD) is associated with bronchiectasis. Therefore, we tried to measure the frequency of IgGSD in patients with bronchiectasis of unclear etiology, and to observe the clinical features of those patients with bronchiectasis and IgGSD.
METHODS: For the outpatients of a university hospital who were diagnosed as bronchiectasis by chest CT, we produced comprehensive history taking and physical examinations, and finally selected 31 patients with bronchiectsis of unclear etiology.
RESULTS: Two patients had total immunoglobulin G deficiency. The frequency of IgGSD was 45.2 percent (n=14). Of them, 13 patients with IgGSD showed isolated IgG3 deficiency and one patient showed combined IgG3 and IgG4 deficiency. When we compared IgGSD group with normal immunoglobulin G subclass group, there were no significant differences in sex, age, and the frequency of sinusitis, bronchial asthma, and the abnormal lung function.
CONCLUSION: In patients with bronchiectsis of unclear etiology, the frequency of IgGSD was comparatively high. There were no significant differences in the clinical characteristics between IgGSD group and normal IgG subclass group.
CLINICAL IMPLICATIONS: In the case of bronchiectais without definite causes, it can be considered to measure the level of immunoglobulin G subclass. It is also probably worthwhile to further evaluate the relationship between IgGSD and bronchiectasis.
DISCLOSURE: Changhwan Kim, No Financial Disclosure Information; No Product/Research Disclosure Information