CLINICAL RELEVANCE OF INTERLEUKIN-1 RECEPTOR ANTAGONIST PLASMA-LEVELSIN RENAL-TRANSPLANT RECIPIENTS

Objectives: In a retrospective study we analyzed the predictive value of interleukin-1 receptor antagonist (IL-1RA) plasma levels in respect to i) prediction of rejection or infection, ii) differential diagnosi s of rejection or infection, and iii) success of rejection treatment. Patients and Methods: IL-1RA levels in plasma samples of renal allogra fted patients with i) an uncomplicated course, ii) rejection, or iii) infection that were obtained prior to or during the beginning of clini cal symptoms were compared. IL-1RA plasma levels were determined using commercially available ELISA-kits. Results: In patients with an uncom plicated postoperative course the highest IL-1RA plasma levels were me asured during the first 2 weeks posttransplant with a mean of 1,135 pg /ml. The levels decreased thereafter during week 3 and 4 posttransplan t to a mean of 542 pg/ml. 1-3 days before the occurrence of symptoms o f rejection or infection, IL-1RA increased stronger in patients with i mpending rejection than in patients who developed an infection (p = 0. 01). IL-1RA is a good indicator of the success of rejection treatment. Patients with a good response to bolus steroids had lower IL-1RA plas ma levels during the week after initiation of antirejection therapy th an patients with a poor response to treatment. Conclusions: Our data s uggest that sequential measurements as well as single determinations o f the IL-IRA plasma levels provide clinically relevant information con cerning i) graft quiescence,)impending rejection, and iii) success of rejection treatment.