Airway invasive aspergillosis
Airway invasive aspergillosis refers to a form of invasive aspergillosis that affects the airways as the major or only feature.
It usually occurs in immunocompromised neutropenic patients and patients with AIDS. Aspergillosis affecting the airways as the major or only feature of the invasive disease is uncommon and is thought to occur only around 7% of cases of intrathoracic aspergillosis 3.
Clinical manifestations can vary and can range from an acute tracheobronchitis, to bronchiolitis to bronchopneumonia.
It is histologically characterised by the presence of Aspergillus organisms deep to the airway basement membrane 1.
Two morphological forms of invasive aspergillosis of the trachea and bronchi have been described 3 :
- intraluminal: circumferential and superficial “pseudomembrane” of necrotic tissue, fibrin and hyphae, which may result in airway occlusion
- multiple nodular plaques: invades adjacent tissues and may lead to broncho-oesophageal and fatal haemorrhage from bronchoarterial fistulation
Imaging spectrum can vary dependent on whether is it an obstructive tracheobronchitis, bronchiolitis or bronchopneumonia:
obstructive tracheobronchitis due to aspergillosis
- most have normal radiographic findings in the acute phase
- occasionally, tracheal or bronchial wall thickening may be seen
- aspergillus bronchiolitis
- typically seen as predominantly peribronchial areas of consolidation
- rarely, there can be lobar consolidation
- it is almost impossible to differentiate aspergillus bronchopneumonia from bronchopneumonia of other causes
- 1. Franquet T, Müller NL, Giménez A et-al. Spectrum of pulmonary aspergillosis: histologic, clinical, and radiologic findings. Radiographics. 2001;21 (4): 825-37. Radiographics (full text) - Pubmed citation
- 2. Logan PM, Primack SL, Miller RR et-al. Invasive aspergillosis of the airways: radiographic, CT, and pathologic findings. Radiology. 1994;193 (2): 383-8. Radiology (abstract) - Pubmed citation
- 3. Drury AE, Allan RA, Underhill H et-al. Calcification in invasive tracheal aspergillosis demonstrated on ultrasound: a new finding. Br J Radiol. 2001;74 (886): 955-8. Br J Radiol (full text) - Pubmed citation
- 4. Thompson BH, Stanford W, Galvin JR et-al. Varied radiologic appearances of pulmonary aspergillosis. Radiographics. 1995;15 (6): 1273-84. Radiographics (abstract) - Pubmed citation
- 5. Greene R. The radiological spectrum of pulmonary aspergillosis. Med. Mycol. 2005;43 Suppl 1: S147-54. Pubmed citation
- 6. Horger M, Einsele H, Schumacher U et-al. Invasive pulmonary aspergillosis: frequency and meaning of the "hypodense sign" on unenhanced CT. Br J Radiol. 2005;78 (932): 697-703. Br J Radiol (full text) - doi:10.1259/bjr/49174919 - Pubmed citation