Discriminant scorecard for diagnosis of invasive pulmonary aspergillosis in patients with acute leukemia.

Invasive pulmonary aspergillosis, a serious opportunistic infection in adult patients with acute leukemia, is difficult to diagnose antemortem. To identify patients with invasive pulmonary aspergillosis without reliance on invasive diagnostic procedures, a discriminant scorecard for invasive pulmonary aspergillosis based on clinical parameters was evaluated in a three-phase study. In phase I, the records of 62 patients, including 15 with invasive pulmonary aspergillosis, were reviewed. Eleven clinical parameters distinguished patients with invasive pulmonary aspergillosis from control subjects. These parameters were combined into a discriminant scorecard. In phase II, the discriminant scorecard was validated by a blinded, retrospective review of 94 consecutive admissions. The discriminant scorecard score was highly associated with the clinical outcome (p less than 0.0005). The sensitivity of the discriminant scorecard was calculated as a range from 62.9 to 92.8 percent and the specificity as a range from 87.5 to 98.3 percent. In phase III, the clinical utility of the discriminant scorecard was determined by its prospective application to 49 consecutive patient admissions. The discriminant scorecard identified patients with invasive pulmonary aspergillosis at an average of 4.1 days prior to clinical recognition of the disease and initiation of amphotericin B therapy. The discriminant scorecard outperformed a complex function based on multiple linear regressions, was easy to use, and did not require difficult calculations. Thus, for this patient population, the discriminant scorecard was an accurate, useful noninvasive screening test for invasive pulmonary aspergillosis. The scorecard allows more rapid clinical identification of patients with this infection and could lead to improved patient survival through earlier diagnostic and therapeutic intervention.