Abstract: The fibrinolytic function of 98 patients with SLE were determined by spectrophotometric assay and immunodiffusion, 19 patients were observed before treatment, 1 month after treatment and 3 months after the disappearance of clinical symptoms. The results showed that the low level of fibrinolytic function correlated to the severity and the refractoriness of the disease, the activity of plasminogen activator inhibitor (PAI) was significantly increased in all patients. The activity ratio of tissue-type plasminogen activator (t-PA):PAI was significantly lower than normal level in the patients with lupus nephritis, not only the activity of PAI increased significantly, but also the activity of t-PA was significantly decreased, so the activity ratio of t-PA:PAI became much lower, the result suggested that it was related to the refractoriness of the disease. In patients in clinical remission, although the activity of PAI was still higher than normal level, the activity of t-PA was also significantly increased, therefore, the activity ratio of t-PA:PAI was nearly normal.

Key words: Lupus erythematosus, systemic, Fibrinolysin, Plasminogen activator, tissuetype, Plasminogen activator inhibitor