COMPARISON OF SERUM GALACTOMANNAN ANTIGEN-DETECTION AND COMPETITIVE POLYMERASE-CHAIN-REACTION FOR DIAGNOSING INVASIVE ASPERGILLOSIS

To improve the diagnosis of invasive aspergillosis (IA), we retrospect ively compared competitive polymerase chain reaction (PCR) and sandwic h ELISA for detection of serum galactomannan (GM) antigen. We studied 281 serum samples collected weekly during the period at risk for IA fr om 41 selected hematology patients. Twenty-two patients had confirmed, probable, or suspected IA, according to clinical and mycologic data. Fifteen of them had positive GM titers (87 samples) and 12 had positiv e PCRs (20 samples). Nineteen of the 20 PCR-positive samples were also GM-positive. Of the 19 patients without IA (83 samples), one had 3 GM -false-positive samples. Neither test anticipated the initiation of an tifungal therapy on the basis of clinical suspicion. Both tests were m ore likely to be positive before death. This study suggests that PCR o n serum samples is not more sensitive than GM detection. However, PCR can improve the specificity of the GM test. Together, these noninvasiv e tests should improve the diagnosis of IA.