Detection of Aspergillus species in blood and bronchoalveolar lavage samples from immunocompromised patients by means of 2-step polymerase chain reaction: Clinical results

Bronchoalveolar lavage (BAL) samples from 67 patients who were at high risk for invasive aspergillosis were examined using a recently developed 2-step polymerase chain reaction (PCR) that detects less than or equal to 10 fg o f Aspergillus DNA in blood and BAL samples in vitro. Thirteen of these pati ents had PCR and diagnostic results positive for Aspergillus infection. Fou r patients with possible invasive aspergillosis also had positive PCR resul ts, and the remaining 50 had negative PCR results. In addition, 907 blood s amples from 218 high-risk patients were screened. Thirty-three patients wit h positive PCR results had invasive aspergillosis; 148 patients had PCR and diagnostic results that were negative, and 34 patients with positive PCR r esults had nonconclusive clinical data. Both blood and BAL testing were per formed for 45 patients. All 8 patients with proven invasive aspergillosis s howed concordance of positive PCR results. Our data suggest that this PCR m ethod has possible clinical value for confirming and improving the diagnosi s of invasive aspergillosis in high-risk patients.