Daily serum inflammatory cytokine (tumor necrosis factor-α, interleukin- 6) monitoring in liver transplantation focusing on allograft rejection: A five-case report

Liver allograft rejection is diagnosed largely based on liver function tests indicating graft damage associated with rejection, but histopathological diagnosis using biopsy is still necessary. Since it can be difficult to distinguish rejection from other causes of graft damage in the absence of liver histopathology, detection of a marker for immune activation and a mediator of inflammation could provide a noninvasive method of diagnosing rejection. Several studies have shown that the postoperative course of inflammatory cytokines such as tumor necrosis factor (TNF)-α1 is predictive of rejection after human orthotopic liver transplantation. We have also previously shown that daily monitoring of serum or plasma interleukin (IL)-6 levels can be useful in predicting long-term graft prognosis.2 However, few reports compare cytokine profiles after liver transplantation. Therefore, in this study, we monitored plasma and serum levels of cytokines in five transplant recipients who eventually lost liver grafts because of relapsing rejection episodes.