Allergic bronchopulmonary aspergillosis complicating COPD is associated with a higher exacerbation rate and a distinct pattern on chest CT scan compared to COPD

Abstract

Recent data support that patients with COPD can experienced associated asthma in an overlap syndrome. This raise hypothesis of specific complications in these patients as allergic broncho-pulmonary aspergillosis (ABPA), usually seen in asthma patients, exhibiting potential specific features when associated to COPD. We compiled 16 cases of ABPA (Patterson criteria) diagnosed in COPD patients (GOLD criteria,Tabaco > 10 PY) in a monocentrique retrospective study, then compared to 16 COPD matched patients on age and FEV1, with similar overall follow up (7.8 years). ABPA-COPD group age was 61.1 years, FEV1 was 36% (1127mL), tobacco consumption was 46.6 PY and 8 out of 16 had known asthma in childhood. ABPA diagnosis was done 6 years after COPD diagnosis. All patients were investigated for specific IgE=19,4 kUI/l, IgE=2684 kUI/l, eosinophilia=1271/mm3. 13/16 had positive IgG, 10 had Aspergillus in sputum. Immediate prick test was positive in 6 out of 7 patients. All received inhaled and oral steroids, 13 patients received oral fungicide and 7 omalizumab. When compared to COPD group, ABPA-BPCO group exhibits higher loss of FEV1 (-83,16 vs -31,14mL/year;p= 0.04). A higher hospitalization rate for exacerbation (1.69 vs 0.53/year;p=0,0007). Using Bhalla scoring, chest CT scan exhibits higher severity in bronchiectasis, mucoid impaction extension but not emphysema (p=0,002; p=0,03; p=0,45) as well as overall extent (10,12 vs 6.8;p= 0,003) ABPA-COPD exhibits a specific pattern and must be considered in COPD patients with recurring exacerbations. CT is distinguishing for diagnosis, in association with biological tools.