CENTRAL BRONCHIECTASIS IN ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS - COMPARATIVE-EVALUATION OF COMPUTED-TOMOGRAPHY OF THE THORAX WITH BRONCHOGRAPHY

Demonstration of central bronchiectasis (CB) with normal peripheral br onchi is an essential requirement for the diagnosis of allergic bronch opulmonary aspergillosis (ABPA). Although the results of bronchography remain the gold standard for demonstration of central bronchiectasis they are not always diagnostic. Moreover, it is an unpleasant invasive procedure which may be difficult to perform in a patient of allergic bronchopulmonary aspergillosis with acute severe asthma. In an attempt to find a safe and effective alternative to demonstrate central bronc hiectasis computed tomography (CT) of the thorax was evaluated against bronchography. Twenty one patients with allergic bronchopulmonary asp ergillosis underwent computed tomography of the thorax followed by bro nchography. Of the 378 bronchopulmonary segments available for analysi s, 42 had to be excluded because of consolidation or non-filling of th e contrast dye, leaving 336 segments for evaluation. CB was identified on CT in all 21 patients. Detailed analysis of the visualized segment s revealed that computed tomography (using 8 mm contiguous scans) iden tified 146 of the 212 segments showing central bronchiectasis on bronc hography (sensitivity 70%) and 114 of the 124, read as normal on bronc hography (specificity 92%). Supplemental 4 mm scans, used in 8 out of 21 patients improved the overall sensitivity of computed tomography to 83%, whilst the specificity remained unchanged at 92%. Thus, computed tomography of the thorax, being more acceptable to the patient, has t he potential of being the investigation of choice for the demonstratio n of central bronchiectasis in patients with allergic bronchopulmonary aspergillosis.