Positive (1→3)-β-D-glucan in blood components and release of (1→3)-β-D-glucan, from depth-type membrane filters for blood processing

BACKGROUND: The false-positive elevation of plasma (1-->3)-beta-D-glucan level, a serodiagnostic test for deep-seated mycosis, is suspected in patients administered with blood components. STUDY DESIGN AND METHODS: (1-->3)-beta-D-Glucan and endotoxin levels in blood components consisting of 12 albumins, 8 immunoglobulins, and 3 blood coagulation factors were measured by fungal infection tests (Fungitec G-test, Seikagaku Co.; the Wako WB003 test, Wako Pure Chemical Industries; and the Endospec ES test, Seikagaku Co.). In vitro release of (1-->3)-beta-D-glucan from the depth-type filters made by cellulose membrane to process blood components was analyzed through an in vitro filtration process as a source of (1-->3)-beta-D-glucan in blood components. RESULTS: The amounts of (1-->3)-beta-D-glucan in blood components ranged from 0 to 7510 pg per mL in the Fungitec G-test, with wide variations among brands. The positive rates over 20 pg per mL were 75 percent in albumin solutions, 40 percent in blood coagulation factors, and 63 percent in immunoglobulin solutions. (1-->3)-beta-D-Glucan levels released from the five depth filters ranged from 5 to 2516 pg per mL. The (1--> 3)-beta-D-glucan level in filtration fluid was decreased by rinsing with distilled water, but rebounded again during the albumin filtration process. CONCLUSION: Depth filters are considered the source of (1-->3)-beta-D-glucan content in some blood components.