DETERMINATION OF THE PRESENCE OF INTERLEUKIN-6 IN BILE AFTER ORTHOTOPIC LIVER-TRANSPLANTATION - ITS ROLE IN THE DIAGNOSIS OF ACUTE REJECTION

Objective The authors evaluated the significance of interleukin-6 (IL- 6) in bile in the diagnosis of acute rejection after liver transplanta tion. Summary Background Data Interleukin-6 in blood has not been show n to be useful as a marker of acute rejection in clinical liver transp lantation. In a rat liver transplantation model, the authors have roun d that bile IL-6 levels correlated well with the severity of rejection as determined histologically, whereas kinetics of serum IL-6 differed among rats without any definite feature related to graft rejection. M ethods Fifty-one patients who underwent orthotopic liver transplantati on between May 1990 and February 1991 at the University of California, Los Angeles, were included in the study. After liver transplantation, bile and blood were collected daily, and IL-6 levels were measured by the enzyme-linked immunosorbent assay.Results Bile IL-6 increased to 1228 +/- 317 pg/mL on the day of transplantation and decreased to 50 p g/ mL or less within 48 hours. Patients who had uneventful postoperati ve courses had low levels of bile IL-6 throughout their hospitalizatio n. In patients with acute rejection, bile IL-6 significantly increased (1090 +/- 990 pg/mL; p < 0.05), but decreased in response to antireje ction therapy. In patients who had liver dysfunction due to ischemic c hange or sepsis, bile IL-6 did not increase. Patients with cholangitis had significantly increased levels of bile IL-6 (146 +/- 47; p < 0.05 ). Interleukin-6 in blood increased with many kinds of complications o ther than rejection and seemed to be less specific than that in bile. Conclusions Measurement of IL-6 in bile may be a useful, noninvasive t ool for diagnosing acute rejection.