In the period of 2000-2005 the authors performed as total of 214 HRCT lung examinations in patients with hematological malignancies associated with defect of immunity. In 30 cases the invasive pulmonary aspergillosis was verified by histology and microbiology. Angioinvasive form was most frequent (63.3%). The bronchoinvasive form proved to be less frequent (20%) as well as combination of both forms (16.7%). In the given clinical context, focal condensations with peripheral halo of ground glass density (halo sign), cavitation with a gas crescent (air crescent sign) and nodules in the centrilobular distribution (tree in bud) may be considered as relatively specific signs of the disease. Specific symptoms of invasive aspergillosis occurred altogether in 62.9% of patients in contrast to 30.8% of cases, where aspergillosis could be diagnosed on the basis of the plain chest X-ray. The halo sign which the authors observed in 50% of patients, in 80% of them during the first week of the disease proved to be most frequent. The present data indicate that HRCT contributes best in the early stage of the disease, where specific signs (especially the halo sign) occur in 80% of cases and there is also less probable fatal course of the disease. Based on this experience the authors included HRCT into the routine examination algorithm in patients with predisposition to the invasive pulmonary aspergillosis. This examination is indicated after at least 4 days of febrile states which does not respond to empirically administered wide-spectrum antibiotics without a known infection agent.

        Key words: lung – invasive aspergillosis – computed tomography