SUCCESSFUL KIDNEY TRANSPLANTATION OF PATIENTS WITH DITHIOTHREITOL REDUCIBLE SERUM AUTOANTIBODIES
H Han, SM Brodt, D Foster and S Hsia Dept. of Pathology and Laboratory Medicine, Allegheny General Hospital, Pittsburgh, PA.

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Unlike serum IgG alloantibodies, the presence of IgM autoantibodies is not a contraindication for receiving a kidney transplant. Dithiothreitol (DTT)which inactivates IgM molecules more effectively than IgG molecules is often used to identify IgM autoantibodies by the DTT reducible antibody reactivity. We report here our experience on the monitoring of patients with autoantibodies by DTT reduction testing and their long-term graft outcome. Two patients with renal dysfunction secondary to systemic lupus erythe-matosus were evaluated for kidney transplantation. Both patients gave autocrossmatch positive results and their serum antibody reactivity was DTT reducible. Their serum panel antibody levels (with 10 sera) were DTT reduced from a range of 78-98% to <3%. A DTT tube method was designed to crossmatch (XM) simultaneously DTT treated and untreated sera with cadaveric donor lymphocytes. Thus 50 XMes (6 sera react to lymphocytes from 24 donors) were done for patient 1 in 5 month's time on the UNOS renal match list until the transplantation. Patient 2 was transplanted after 57 XMes (8 sera versus 27 donors)in 12 months'listing time. All but one treated sera gave positive XM results and DTT treated sera gave negative results. Both patients had uneventful post-transplantation courses with creatinine of <1.2 mg/dl at 1 year. Patient 1 maintained a stable graft function for 7 years and had a dysfunctional graft in the 8th years due to chronic rejection. This patient is currently being evaluated for a 2nd transplant. Patient 2 has currently stable graft function with the creatinine of 1.1mg/dl at 6 years post-transplantation. In conclusion, patients with DTT reducible autoantibodies can be safely transplanted with long-term functioning graft.