Abstract:

Objective: To evaluate the curative efficacy of tacrolimus (FK506) combined with corticosteroids in the treatment of idiopathic membranous nephropathy (IMN), and to analyze the response of anti-M-type phospholipase A2 receptor (PLA2R) antibody to the treatment. Methods: Sixty-one adult IMN patients were divided into FK506 group (FK506 combined with corticosteroids, n=24) and CTX group (cyclophosphomide combined with corticosteroids, n=37) according to their willing to the acceptance of different immunosuppressives. The remission rates of the patients at 4, 8, 12 and 24 weeks after treatment in two groups were analyzed. The ELISA method was used for the detection of serum anti-PLA2R antibodies of the patients before and after treatment. The antibody level changes were observed and the difference of remission rates was compared between the antibody positive patients and the negative patients in FK506 group. Results: The total remission rates of the patients in FK506 and CTX groups 24 weeks after treatment were 91.7% and 64.9% respectively and the total remission rate of the patients in FK506 group was significantly higher than that in CTX group(P<0.05). The total remission rates at 8, 12, 24 week after treatment and the partial remission rates at 12 and 24 weeks in FK506 group were significantly higher than those in CTX group (P<0.05). The anti-PLA2R antibody positive rates in FK506 group and CTX group were 75.0% and 70.3%, respectively; the negative conversion rate of anti-PLA2R antibody at 24 weeks after treatment in two groups were 61.6% and 57.7%, respectively; there were no significant differences between two groups(P>0.05).The total remis sion rates of the antibody positive patients and negative patients at baseline in FK506 group 24 weeks after treatment were 88.9% and 100.0%, respectively; there was no significant difference (P>0.05). Except the characteristic side effects of corticosteroids, the patients in FK506 group presented no hyperglycemia, tubulointerstitial damage, hepatic lesion or neurotoxicity. But the patients in CTX group showed mild hepatic lesion or gastrointestinal symptoms. Conclusion: The remission rate of FK506 combined with corticosteroids is higher than that of CTX combined with corticosteroids in the treatment of IMN patients. FK506 treatment has relatively rapid effect and less side effects as well. The negative conversion of serum anti-PLA2R antibody follows the remission after treatment; however, the negative conversion rate has no significant difference between FK506 group and CTX group. The remission rate of IMN patients treated with FK56 combined with hormone has no relationship with the baseline anti-PLA2R antibody.

Key words: tacrolimus, glomerulonephritis, membranous, receptor, M-type phospholipase A2, antibody