Differential diagnostic use of interleukin patterns in patients being monitored after transplantation

Background and aim: We investigated how far the determination of selected i nterleukins in bodily fluids of patients who had received kidney allografts can help to confirm the diagnosis of complications after transplantations. Materials and methods: Levels of soluble interleukin-2-receptor, interleuk in 6 and interleukin 8 were determined in serum and urine of 79 patients. A ccording to the type of diagnosis obtained with histological, serological. and microbiological methods and to the clinical course, the groups "stable graft function without complication", "allograft rejection", "cytomegalovir us infection", "systemic extrarenal bacterial infection", "urinary tract in fection" and "pyelonephritis" were created. Results and conclusions: The ac tivation of the immune system in different ways depending on the trigger su bstance (alloantigen, virus, bacterium) and the possibility to differentiat e systemic and local processes cause typical patterns of interleukin levels in serum and urine in conjunction with the above mentioned complications a fter kidney transplantation. Cytomegalovirus infections and systemic extrar enal bacterial infections differ from rejection by the unchanged urine inte rleukins IL 6 and IL 8, the local urinary tract infections differ from reje ction by the unchanged serum interleukins. Acute pyelonephritis differs fro m rejection by the significantly higher serum IL 6 level. During our daily clinical work, the practical interleukin determinations were proven to be a n important tool for early and differential diagnosis of complications afte r kidney transplantation. (C) 2001 Elsevier Science B.V. All rights reserve d.