2 STRATEGIES FOR MANAGING INVASIVE ASPERGILLOSIS - A DECISION-ANALYSIS

We devised a diagnostic approach based on screening plasma for an Aspe rgillus antigen with use of a sandwich enzyme-linked immunosorbent ass ay (ELISA), thoracic computed tomographic scanning, and radionuclide i maging for managing patients at risk for invasive aspergillosis. We us ed a decision analytic model to compare this alternative strategy with the conventional strategy, which relies only on the presence of clini cal symptoms, persistent fever, and chest roentgenographic findings. U se of the alternative strategy reduced the number of patients who woul d receive antifungal treatment empirically, but this strategy was more expensive. The specificity of the sandwich ELISA had a significant im pact on cost, but the sensitivity did not. A 13% prevalence of infecti on resulted in equal costs for both strategies. As much as 43.3% of th e patients treated empirically could be given liposomal amphotericin B (L-AmB) before the conventional strategy became the most expensive. T he costs of the alternative strategy were less than those of the conve ntional strategy when >5.3% of all patients, irrespective of strategy, were treated with L-AmB.