Predictive value of a positive nasal swab for Aspergillus SP in the diagnosis of invasive aspergillosis in adult neutropenic cancer patients

To evaluate the value of a positive nasal swab for Aspergillus in the diagn osis of invasive aspergillosis, we prospectively evaluated nasal colonizati on in 173 episodes of neutropenia in 92 patients with hematological maligna ncies. Weekly nasal swabs were taken, and the patients were followed until death or resolution of neutropenia. The outcome variables were the developm ent of invasive aspergillosis, empirical antifungal therapy and death. In 3 1 episodes of neutropenia (18%) there was at least one positive nasal swab for Aspergillus sp. Only two patients developed invasive aspergillosis, bot h with a positive nasal swab (p = 0.03). The positive and negative predicti ve values of a nasal swab were 6.4% and 100%, respectively. There was no di fference between patients with positive or negative swabs regarding antifun gal therapy or death. In this population of patients, a nasal swab for Aspe rgillus sp. had a low positive predictive value and a high negative predict ive value for invasive aspergillosis. (C) 1999 Elsevier Science Inc.