Aetiology of bronchiectasis in Guangzhou, southern China
Aetiologies of bronchiectasis in mainland China and their comparisons with those in western countries are unknown. We aimed to investigate bronchiectasis aetiologies in Guangzhou, southern China, and to determine ethnic or geographic differences with reports from western countries. Consecutive patients with steady-state bronchiectasis were randomly recruited. Past history was meticulously extracted. Patients underwent physical examination, saccharine test, humoral immunity assays, gastroesophageal reflux scoring and sputum culture. Fiberoptic bronchoscopy, total immunoglobin E (IgE) and Aspergillus fumigatus-specific IgE measurement, 24-h gastroesophageal pH monitoring and miscellaneous screening tests were performed, if indicated. This entailed comparisons on aetiologies with literature reports. We enrolled 148 patients (44.6 ± 13.8 years, 92 females), most of whom had mild to moderate bronchiectasis. Idiopathic (46.0%), post-infectious (27.0%) and immunodeficiency (8.8%) were the most common aetiologies. Miscellaneous aetiologies consisted of asthma (5.4%), gastroesophageal reflux (4.1%), aspergillosis (2.7%), congenital lung malformation (2.0%), Kartagener syndrome (1.4%), rheumatoid arthritis (1.4%), chronic obstructive pulmonary disease (0.7%), Young's syndrome (0.7%), yellow nail's syndrome (0.7%), eosinophilic bronchiolitis (0.7%) and foreign bodies (0.7%). No notable differences in clinical characteristics between idiopathic and known aetiologies were found. Ethnic or geographic variations of aetiologies were overall unremarkable. Idiopathic, post-infectious and immunodeficiency constitute major bronchiectasis aetiologies in Guangzhou. Clinical characteristics of patients between known aetiologies and idiopathic bronchiectasis were similar. Ethnicity and geography only account for limited differences in aetiologic spectra. These findings will offer rationales for early diagnosis and management of bronchiectasis in future studies and clinical practice in China.