Objective: To compare three different regimens of thymoglobulin induction.
Methods: One hundred seventy two patients submitted to renal transplantation from a dead donor were divided into three groups according to the total number of thymoglobulin doses used in the post-transplantation surgery: Group 1, until 14 doses - May 2002 to June 2004 (n = 48); Group 2, until 7 doses - July 2004 to December 2006 (n = 57); Group 3, until 4 doses - January 2007 to July 2009 (n = 67). The three groups were compared according to the main outcomes.
Results: The main demographic differences among the groups were: greater dialysis time in Group 3 (p < 0.001 for Group 1; and p = 0.04 for Group 2); donor age, greater in Groups 2 and 3 (p = 0.02; p = 0.01, respectively); and cold ischemia time progressively greater from Group 1 to 3: 19.5 ± 5.1 to 24.6 ± 5.7 hours (p < 0.001). In relation to the inhibitor of calcineurin, the relation Tac/Csa was 14.6/66.7% in Group 1, 78.9/12.3% in Group 2 and 100/0% in Group 3. Reflecting the increase in cold ischemia time, the incidence of delayed graft function was 64.6%, 68.4% e 82.1% in Groups 1, 2 and 3, respectively (p = ns). The incidence of acute rejection was similar in the three groups: 16.7% (1); 16.3% (2) and 16.4 (3) - p = ns. The prevalence of viremia for cytomegalovirus was 61.7% in Group 1, 66.1% in Group 2 and 83.3% in Group 3 (p = ns). There were no difference related to the number of infected cells with cytomegalovirus in antigenemia, according to the groups, however, patients in Group 3 had an earlier diagnosis: from 64.3 ± 28.5 days in Grup 2, to 47.1 ± 22.5 days, in Group 3, p < 0.001. Survival of the graft in one year was 89.6%, 92.9% and 91.0%, in Groups 1, 2 and 3, respectively (p = ns). The graft function was much better with the lower doses of thymoglobulin: Group 1: 57.0 ± 20.0 mL/min; Group 2: 67.0 ± 18.4 mL/min (p = 0.008); Group 3: 71.2 ± 18.4 mL/min (p < 0.001, Group 1 versus Group 3; p = 0.06, Group 1 versus Group 2). There was a significant reduction in the costs of induction protocol from U$ 7,567.02 to U$ 3,485.56 (p < 0.001).
Conclusions: The total number of thymoglobulin doses for immunologic induction could be reduced in a safe and effective way, without a negative impact in graft rejection or survival, preserving renal function and being significantly cheaper.