COMPARISON OF FK506-BASED AND CYCLOSPORINE-BASED IMMUNOSUPPRESSION INPRIMARY ORTHOTOPIC LIVER-TRANSPLANTATION - A SINGLE-CENTER EXPERIENCE

FK506 has been proven effective for prevention and treatment of liver allograft rejection. Herein, we compare FK506-based immunosuppression with an effective quadruple immunosuppressive regimen, including cyclo sporine and antithymocyte globulin. The results of a single center par ticipating in the European multicenter FK506 study are reported, inclu ding immunosuppressive efficacy as well as toxicity. One-year patient and graft survival was 96.7% and 90.0% for the CsA group and 90.2% and 88.5% for the FK506 group, which is not statistically different. The incidence and severity of acute rejection episodes during the first po stoperative year was similar in both treatment groups with 34.4% and 3 3.3% for the FK506 and CsA treatment group, respectively. Immunosuppre ssive potency was better for the FK506 group compared with the CsA gro up according to the incidence of chronic rejection. Furthermore, 5 pat ients (8.3%) required conversion to FK506 for immunological reasons, i .e., refractory acute or chronic rejection. The incidence of moderate and severe neurotoxicity during the early postoperative period was hig her in the FK506 group (21.3%) compared with the CsA group (11.7%), wh ile the incidence of renal insufficiency and acute renal failure was s imilar (18.0% and 18.3% for the FK506 and CsA treatment groups, respec tively). The incidence of CMV infection was significantly higher under treatment with CsA (25.0%) than with FK506 (6.6%) (P less than or equ al to 0.05), while the incidence of pneumonia (13.1% and 13.3%), chola ngitis (29.5% and 26.7%), and urinary tract infection (39.3% and 28.3% for the FK506 and CsA treatment groups, respectively) was similar in both treatment groups. However, infection was more serious in some cas es treated with FK506, and evolved as the main cause of death in the F K506 treatment group. Therefore, caution should be paid to overimmunos uppression and toxicity in FK506-treated patients. Regarding the monit oring of FK506, FK506 plasma level failed to be a reliable indicator, and therefore we recommend measurement of whole blood FK506 levels. Ou r data indicate that immunosuppressive potency of FK506 is greater tha n that of CsA, especially concerning the incidence of chronic rejectio n.