Transmission of human T-lymphotrophic virus type I infection to a neonatal infant by transfusion of washed and irradiated red cells.

Abstract

Human T-lymphotropic virus type I and/or II (HTLV-I/II) may be transmitted by the transfusion of blood and blood components. Several factors are critical to the efficiency of transmission. These include the number of contaminating white cells, the component volume, and the age of the component. After look-back notification, there was an investigation of the HTLV-I/II serostatus of three patients who had received blood from a donor now found to be positive for HTLV-I antibodies by enzyme immunoassay and Western blot. The donor red cell unit was group O negative and cytomegalovirus antibody negative; it was washed and irradiated at 2800 cGy and aliquoted into six small-volume transfusions for four neonatal infants. Three of the four patients were available for testing 3.5 years after their exposure. The fourth neonatal infant died on Day 11 of life. The three tested infants received 14, 14, and 44 mL of component, respectively. HTLV-I seroconversion was documented by enzyme immunoassay and Western blot (p19, p24) and occurred only in the patient receiving 44 mL. On the basis of quality control data, it is estimated that the affected infant received 8 x 10(7) white cells in the 44-mL aliquot. Washing and irradiation will not necessarily eliminate HTLV-I transmission.