Light microscopical appearance of invasive pulmonary aspergillosis showing vessel occlusion with thrombus and distal infarction (Haematoxylin and eosin, x100)
Bronchoscopic manifestations of Aspergillus tracheobronchitis. (a) Type I. Inflammatory infiltration, mucosa hyperaemia and plaques of pseudomembrane formation in the lumen without obvious airway occlusion. (b) Type II. Deep ulceration of the bronchial wall. (c) Type III. Significant airway occlusion by thick mucous plugs full of Aspergillus without definite deeper tissue invasion. (d) Type IV. Extensive tissue necrosis and pseudomembrane formation in the lumen with airway structures and severe airway occlusion (Wu 2010).