Invasive aspergillosis in the immunocompromised host: utility of computed tomography and bronchoalveolar lavage

Bronchoalveolar lavage is performed almost routinely in immunocompromised patients with suspected pneumonia, but it has a low yield in the diagnosis of pulmonary aspergillosis. The aim of this study was to determine whether computed tomography (CT) is helpful in determining the likelihood of a positive bronchoalveolar lavage by allowing distinction of patients with angioinvasive aspergillosis from those with Aspergillus bronchopneumonia.

A retrospective study was performed including consecutive immunocompromised patients with suspected pneumonia who underwent CT scanning of the chest and bronchoalveolar lavage and who had definite diagnosis of pulmonary aspergillosis. The CT scans were reviewed by two chest radiologists and classified as showing features consistent with angioinvasive or airway invasive aspergillosis. Twenty-one patients met the inclusion criteria. Bronchoalveolar lavage was positive for fungi in two of 11 patients with CT findings consistent with angioinvasive aspergillosis and eight of 10 patients with CT scans consistent with Aspergillus bronchopneumonia (P < 0.01, chi-squared test). CT findings of angioinvasive aspergillosis included nodules measuring 1-3.5 cm in diameter in six, segmental consolidation in three, and both nodules and segmental consolidation in two patients. CT findings of Aspergillus bronchopneumonia including peribronchial consolidation in five, small centrilobular micronodules in one, and both in four patients.

Chest CT is helpful in determining the likelihood of successful diagnosis of pulmonary aspergillosis by bronchoalveolar lavage.