PLASMA (1-]3)-BETA-D-GLUCAN MEASUREMENT IN DIAGNOSIS OF INVASIVE DEEPMYCOSIS AND FUNGAL FEBRILE EPISODES

(1-->3)-beta-D-glucan is a characteristic fungal cell-wall constituent . To assess the clinical usefulness of this glucan in screening for in vasive fungal infection or fungal febrile episodes, we measured the pl asma concentration at the time of routine blood culture in 202 febrile episodes by means of factor G, a horseshoe-crab coagulation enzyme th at is extremely sensitive to this polysaccharide. With a plasma cut-of f value of 20 pg/mL, 37 of 41 of definite fungal infections (confirmed at or by microbiology) had positive results of 59 episodes of non-fun gal fever, or collagen diseases had concentrations below the cut-off v alue (specificity 100%). Of 102 episodes of fever of unknown origin, 2 6 had plasma glucan concentrations of more than 20 pg/mL. With those 1 02 cases taken as non-fungal infections, the positive predictive Value of the test was estimated as 59% (37/63), the negative predictive val ue as 97% (135/139), and the efficiency as 85% (172/202). The positive predictive Value should improve if there were a sensitive gold standa rd that could discriminate fungal from non-fungal infections. Causativ e fungi included candida, aspergillus, cryptococcus, and trichosporon. Determination of plasma (1-->3)-beta-D-glucan with factor G is a high ly sensitive and specific test for invasive deep mycosis and fungal fe brile episodes, and will substantially benefit immunocompromised patie nts.