Myung-Duk Lee¹, Dong Goo Kim¹, In Sung Moon¹, Ji Il Kim², Deuk Young Oh³, Sang Il Kim⁴, Shinn Young Kim², Chong Young Choi⁵, Jae Myung Park⁵, Seung Eun Nha⁶, Eun Sun Chung⁷

¹Department of Surgery, The Catholic University of Korea, Seoul, Korea; ²Department of Surgery, The Catholic University of Korea, Seoul, Korea; ³Department of Plastic Surgery, The Catholic University of Korea, Seoul, Korea; ⁴Department of Infectious Disease, The Catholic University of Korea, Seoul, Korea; ⁵Department of Gastroenterology, The Catholic University of Korea, Seoul, Korea; ⁶Department of Radiology, The Catholic University of Korea, Seoul, Korea; ⁷Department of Pathology, The Catholic University of Korea, Seoul, Korea

Background: To reverse the deteriorated renal function of the small bowel transplants (SBTx) under the Tacrolimus monotherapy, Sirolimus combined immunosuppression with lowered dose  Tacrolimus was administered.

Patients and Method: A total of 5 SBTx of this institution since 2004 were included in this study. Two were living-related donor transplants(LDTx) and 3 deceased donor transplants(DDTx). Tacrolimus was the primary immunosuppressant and the induction was Daclizumab, Basiliximab, Thymoglobulin or Alemtuzumab depending on the situation. Target serum trough level of Tacrolimus for the first 3 months of transplantation was 10 to 15 ng/dL, then 5 to 10 ng/dL. When serum BUN/Cr concentration was persistent above 30/1.8 mg/dL, Sirolimus (targeted above 10 ng/dL) was administered with lowered dose Tacrolimus (targeted 5-10 ng/dL for the first 3 months post-transplant, and then 2-5 afterwards).

Result: After acute rejection episode in Tacrolimus monotherapy of the #1 DDTx, BUN/Cr stayed above the criteria. Sirolimus was administered from the 5th month post-transplant, and BUN/Cr decreased below 20/1.2 mg/dL. In #2 DDTx, Sirolimus combination from a month post-transplant resulted in normalized BUN/Cr, but the patient died after 3 months due to unresolved septic complications. In #3 DDTx, Sirolimus combination from a month post-transplant returned renal function to normal. The #2 LDTx of a 3-year-old girl had been in good renal function for 5 years of transplantation, when segmental graft resection was performed for chronic rejection. Postoperative electrolyte imbalance and elevated BUN/Cr returned to normal after Sirolimus combination. The #1 LDTx has been in marginal chronic renal failure with proteinuria for 6 years post-transplant, when Sirolimus combination regimen was applied. Her renal function improved clearly, but could not stay alone within normal limits.

Summary: Sirolimus combination with low dose Tacrolimus was effective for the graft safety and recovery of the compromised renal function of the SBTx with Tacrolimus monotherapy.