Donor Screening for Human T‐cell Lymphotrophic Virus 1/2: Changing Paradigms for Changing Testing Capacity

Organ Procurement and Transplant Network (OPTN) policy currently requires the testing of all potential organ donors for human T‐cell lymphotrophic virus (HTLV)‐1/2. Most Organ Procurement Organizations (OPO) use the Abbott HTLV‐I/HTLV‐II Enzyme Immunoassay (EIA). This assay will no longer be manufactured after December 31, 2009; the only commercially available FDA‐licensed assay will be the Abbott PRISM HTLV‐I/II assay which poses many challenges to OPO use for organ donor screening. As a result, screening donors for HTLV‐1/2 in a timely manner pretransplant after December 31, 2009 will be challenging. The true incidence of HTLV‐1 in United States (U.S.) organ donors is not well described but appears to be low (∼0.03–0.5%). HTLV‐1 is associated with malignancy and neurological disease; HTLV‐2 has not been convincingly associated with disease in humans. Donors that are HTLV‐1/2 seropositive are infrequently used despite most results being either false positive or resulting from HTLV‐2 infection. There is urgent need to encourage the development of assays, instruments and platforms optimized for organ donors that can be used to screen for transmissible disease in donors; these must have appropriate sensitivity and specificity to identify all infections while minimizing organ loss through false positive testing. HTLV‐1/2 screening in the solid organ donor population is increasingly challenging: donors that are HTLV1/2 positive are infrequently used despite most results being either false positive or due to HTLV‐2, which has not been associated with disease. See editorial by Humar on page 199.