A questionnaire-based study on the role of environmental factors in allergic bronchopulmonary aspergillosis

BACKGROUND AND AIMS: Allergic bronchopulmonary aspergillosis (ABPA) is an immunological disorder caused by hypersensitivity against Aspergillus fumigatus. The pathogenesis of ABPA remains unknown. Few studies have investigated the role of environmental factors in pathogenesis of ABPA. Herein, we investigate the role of environmental factors in ABPA. MATERIALS AND METHODS: In this prospective case-control study, consecutive patients with asthma (Aspergillus sensitized and unsensitized) and ABPA were investigated using a standardized questionnaire to enquire into their demographic characteristics, clinical details, exposure to organic matter and living conditions (home environment, presence of moisture in the walls, and others). Asthma severity and control was assessed using the 2002 The Global Initiative for Asthma (GINA) recommendations and asthma control test, respectively. RESULTS: During the study period, 202 subjects of asthma (103 and 99 Aspergillus unsensitized and sensitized asthma, respectively) and 101 ABPA with a mean (SD) age of 35.3 (14.7) years were included. The baseline characteristics were similar in the two groups except for a higher prevalence of severe persistent asthma in the ABPA group (79% vs. 44%, P = 0.0001). No significant differences in environmental factors were noted in the ABPA population compared to asthmatic patients except for a higher rural residence in ABPA (47% vs. 66%, P = 0.007). CONCLUSIONS: The study found no significant environmental differences in ABPA compared to asthmatic patients. It is likely that environmental factors are not the primary pathogenetic factors in causation of ABPA.