Methods: Samples tested were from pt with classic risk factors for IPA defined by EORTC/MSG criteria & that had been prospectively banked in our BAL repository. Each case of IPA identified was matched to 2 high-risk control pt without IPA or other invasive fungal infection. Samples were thawed, vortexed, centrifuged, & 100μl of supernatant was applied to the AspLFD. Results were interpreted at 15 min as +, ++, +++, or negative by 3 independent, blinded observers. Test characteristics, including sensitivity, specificity, positive predictive value (PPV) & negative predictive value (NPV) were calculated.
Results: Samples from 14 pt with proven/probable IPA by EORTC/MSG criteria and 28 control pt without IPA were tested. Median age was 58 (range 22-87); 28 were men. Age & gender distribution were similar between cases & controls. Among IPA cases, 9 were on T cell depleting agents, 4 on high-dose steroids, & 3 had prolonged neutropenia. Among non-IPA controls, risk factors were T cell depleting agents (17), high-dose steroids (11), and stem cell transplant (2). Of the 14 pt with IPA, AspLFD was positive in 3, negative in 9; in 2, the internal control line did not display & these were considered invalid. Of 6 pt receiving an azole, 3 had a positive AspLFD test. AspLFD was negative for all 28 BAL in the non-IPA group. AspLFD showed low sensitivity (25%) & high specificity (100%); PPV was 100% & NPV was 75%. Accuracy of the test was 77.5%.
Conclusion: A positive AspLFD test in BAL of pt with classic risk factors for IPA could be useful for ruling in proven/probable IPA because of its high specificity. However, the use of AspLFD as a screening test for IPA is limited by its poor sensitivity.
K. A. Linder,
C. A. Kauffman, None
M. H. Miceli, None