Prevalence of allergic bronchopulmonary aspergillosis in patients with bronchial asthma.

ABSTRACT

Two Hundred patients with bronchial asthma were studied to identify the prevalence of allergic bronchopulmonary aspergillosis (ABPA). The patients selected required intermittent short courses of steroids and their mean duration of illness was 12 years. Absolute eosinophil count was > 500/mm3 in 53% of the cases. Chest X-rays showed small homogenous shadows with patchy infiltrations in 25% and fluctuating pneumonic shadows in 14% of the cases. Raised specific IgG and positive serum precipitin against Aspergillus fumigatus (AF) were present in 24% and 13%, respectively. Cases with radiological and immunological suspicion were further investigated for ABPA. Skin tests for Type-I and Type-III reactivity were positive with AF extract in 87% (n = 47) and 36% (n = 47) of the cases. A thorax CT of 31 patients showed central bronchiectasis in 24 cases, labeling these patients as ABPA-CB (ABPA with central bronchiectasis) and an other 7 as ABPA-S (serological positive). CT was not done in one case who, because of other positive findings, was also labeled as ABPA-S. Thus, these 32 asthmatics were found to have ABPA. Among them, there was raised specific IgG (100%) and raised specifc IgE against AF (100%), positive skin test for Type-I and Type-III reactivity (100% and 53%) against AF. There was elevated total IgE (100%, n = 29), a positive family history of asthma (63%), peripheral eosinophilia (100%) and a history of passage of brownish plugs (31%). Radiological findings suggested soft shadow with infiltration in 31% and fluctuating pneumonic shadows in 69% of cases. CT Thorax (n = 31) showed central bronchiectasis in 78% of theses patients. Based on the present data, the prevalence of ABPA in bronchial asthma patients is 16% (12% with central bronchiectasis and 4% only serologically positive). Therefore, patients should be investigated and diagnosed in an early phase of ABPA (ABPA-S) and should be treated to prevent permanent lung damage.