Low-dose prophylactic intravenous immunoglobulin does not prevent HLA sensitization in left ventricular assist device recipients

Background. The use of left ventricular assist devices is associated with human leukocyte antigen ( HLA) allosensitization. We investigated whether prophylactic treatment with low-dose intravenous immunoglobulin ( IVIG), analogous to the use of IgG anti-D ( anti-Rh) in preventing Rh immunization, can abrogate HLA allosensitization after left ventricular assist device implantation. Methods. We retrospectively reviewed the data from 84 consecutive heart failure patients who underwent implantation of a left ventricular assist device as a bridge to transplantation. After implantation, panel reactive antibody ( PRA) was measured biweekly to assess sensitization ( defined by PRA > 10%). Patients who were sensitized before left ventricular assist device implantation were excluded from further analysis ( n = 12). Patients who either did not require perioperatively transfusions of cellular blood products or received other immunomodifying regimens were also excluded from further analysis ( n = 21). The rest of the patients were divided into two groups based on whether they received IVIG, 10 g daily for 3 days ( IVIG group, n = 26; non-IVIG group, n = 25). The decision as to whether patients received IVIG was not randomized but was based on surgeon preference. Results. The sensitization rates ( expressed as ratio of sensitized patients to total patients at risk) in the two groups were similar at consecutive time points ( 2, 4, 6, 8, 12, 20 weeks) after left ventricular assist device implantation. Also, mean PRA at the same time points did not differ between the two groups. Overall, 34.6% ( 9 of 26) of the IVIG group became sensitized during mechanical support, compared with 32% ( 8 of 25) of the non-IVIG group ( p = 1.0). A PRA of 90% or greater ( high-degree sensitization) occurred in 15.3% ( 4 of 26) of the IVIG group and 12.0% ( 3 of 25) of the non-IVIG group ( p = 0.5). Conclusions. The use of low-dose prophylactic IVIG after left ventricular assist device implantation affects neither the incidence nor the severity of HLA allosensitization.