[Urinary tissue-type plasminogen activator (tPA) in renal transplant patients]

We have previously suggested that an appearance of FDP D-dimer fragment into the urine predicts the reversibility of acute renal transplant rejection. In the present study, we observed urinary tissue-type plasminogen activator (tPA), which is a fibrinolytic enzyme and produces D-dimer, in 51 renal transplantation patients. Urinary tPA values are generally higher in transplantation patients except on chronic rejection than in healthy controls. High values just before onset of rejection (increase of serum creatinine value), deterioration at onset phase and gradual elevation from peak phase toward recovery phase were observed in urinary tPA of 6 reversible acute rejection episodes. Urinary D-dimer values changed following urinary tPA values in serial observation of 2 cases. In conclusion, immunological reaction accompanying by functional and organic renal impediments may result in loss of fibrinolytic activity, decrease in urinary tPA and D-dimer. This findings suggest theoretically that the supplemental tPA administration prevents the progression of rejection reaction.