Utility of computed tomography (CT) and of fine needle aspiration biopsy (FNAB) in early diagnosis of fungal pulmonary infections. Study of infections from filamentous fungi in haematologically immunodeficient patients

The purpose of this study was to evaluate the sensitivity of percutaneous computed tomography (CT)-guided lung biopsy in the early diagnosis of fungal pulmonary infections. Between 1997 and 2003, 18 haematologically immunodeficient patients with suspected filamentous fungi infection and negative bronchoalveolar lavage (BAL) underwent percutaneous pulmonary biopsy to diagnose the nature of the infection. In all cases, infection developed during the post-chemotherapy bone marrow aplasia period. Thirteen out of 18 patients had histologic findings positive for fungal infection: 8 Aspergillus and 5 Mucor. In 3 cases, biopsy was not specific, and in one case, the tissue sample was inadequate for a diagnosis; however, clinical course and response to drugs were compatible with fungal infection. In one patient, biopsy was positive for bronchoalveolar carcinoma. The sensitivity of percutaneous CT-guided biopsy was 80% and its positive predictive value was 100%. We only had one pneumothorax as a complication. Percutaneous CT-guided lung biopsy is an easy, safe and reliable procedure to obtain diagnostic material. Histological discrimination between Aspergillus and Mucor is important in order to plan the correct therapeutic protocols, as Mucor is usually resistant to azoles.