PROSPECTIVE SANDWICH ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR SERUM GALACTOMANNAN - EARLY PREDICTIVE VALUE AND CLINICAL USE IN INVASIVE ASPERGILLOSIS

Background. The delay between the onset of invasive aspergillosis and the start of antifungal therapy is crucial for the patient's recovery. Early diagnosis is difficult in cancer patients through lack of preco cious specific signs. We have investigated the clinical usefulness of circulating Aspergillus antigen monitoring in pediatric hematology pat ients with a new sensitive sandwich enzyme-linked immunosorbent assay. Methods. A prospective study was conducted by assessing circulating g alactomannan levels in high risk patients. Thirty-seven patients studi ed during an 18-month period were evaluated twice weekly during neutro penic phases with the sandwich enzyme-linked immunosorbent assay for s erum Aspergillus galactomannan. Results. Twelve patients had one or mo re episodes of positive circulating galactomannan detection, 10 of who m developed presumptive invasive aspergillosis. The clinical and radio logic signs occurred at a mean of 13.4 days (range, 0 to 48) after cir culating galactomannan detection and reversed in 6 patients treated wi th amphotericin B at the same time circulating galactomannan detection became negative. Reappearance of circulating galactomannan was observ ed during subsequent neutropenic periods in 3 patients. Conclusions. T he detection of galactomannan at concentrations as low as 1 ng/ml can be useful for the early initiation of antifungal therapy and monitorin g treatment in clinically documented lung aspergillosis. This techniqu e coupled with chest computed tomography could help to restrict the ne ed of invasive diagnostic procedures in fragile patients.