Detection of Aspergillus galactomannan by ELISA (Kit Sanoti Diagnostics Pasteur)
Invasive aspergillosis has increased in frequency and mortality in recent years. The overall mortality from invasive disease has been reported to be as high as 90%. The diagnosis of invasive aspergillosis is often difficult to make. We performed a prospective study of Aspergillus antigenemia in patients with hematologic malignancy. This test was an ELISA (enzyme linked immunosorbent assay) for the detection of circulating Aspergillus galactomannan (SANOFI-PASTEUR), at concentration as low as 1 ng/ml. 226 serum samples from 50 patients were tested (mean 4,5/patient). Fifteen patients (62 samples) had positive results. Three patients had low levels of galactomannan, near the sensitivity of the assay, and was not confirmed later. Six of the other 12 patients with invasive aspergillosis had cultures with Aspergillus sp. Only one patient, with suspected disease but no cultural evidence, had no detectable antigen in any of the six samples studied. Two samples over the threshold of 1 ng/ml enhance specificity to 100% and sensitivity to 92%. This test allows to make the diagnosis 2 at 15 days before cultures, in 5 of 6 patients. Correlation was observed between antigen concentrations and clinical evolution. Antigen concentrations tended to rise as infection progressed, and to decrease as infection is controlled. This test is a real progress in the diagnosis of invasive aspergillosis in immunocompromised patients.
Full conference title:
The 2nd Meeting of the European Confederation of Medical Mycology