Abstract
Background and Aims
Patients with IgA nephropathy (IgAN) presented proteinuria≥1g/d and eGFR≥50ml/min/1.73m2 after supportive treatment had been advised 6-month course of corticosteroids therapy. Update of Oxford classification of IgAN had recommended crescents be added to the MEST score for they were predictive of outcome. Whether we should take some more positive therapy for crescents?
Method
We conducted a single-center, retrospective cohort study enrolling 46 patients from 2017.01 to 2018.06, diagnosed with IgAN by renal biopsy. Eligible patients had proteinuria of 0.5∼3.5g/d, eGFR≥30ml/min/1.73m2 and crescent proportion <50%. Patients were divided into two groups, one for classical steroid treatment (intravenous methylprednisolone 0.25g/d for 3 days at the beginning of months 1, 3 and 5, plus oral prednisone 0.5 mg/kg/d for 6 months, called 1-3-5 Group) and the other assigned an optimized steroid therapy (intravenous methylprednisolone 0.25g/d for 3 days at the beginning of months 1, 2 and 3, plus oral prednisone 0.5 mg/kg/d for 6 months, called 1-2-3 Group). The primary endpoint was remission of proteinuria, secondary endpoint was deterioration in renal function.
Results
There were 23 patients in each group and no significant differences in age, gentle, baseline proteinuria and eGFR between the two groups, except for the proportion of crescents (for Oxford C1 and C2: 52.5% and 13% in 1-3-5 Group vs. 95.7% and 4.3% in 1-2-3 Group respectively, p=0.001). After 6 months therapy, proteinuria in 1-3-5 Group was 0.5(0.2,0.8)g/d (vs. 1.2(0.8,2.6)g/d at baseline, p <0.001) and that in 1-2-3 Group was 0.3(0.2,0.6)g/d (vs. 1.5(0.7,2.6)g/d at baseline, p <0.001). 78.3% of patients in 1-3-5 Group had got remission of proteinuria, while 95.7% in 1-2-3 Group (p=0.187). The 6th month eGFR in 1-3-5 Group was 80.7(59.8,116.2)ml/min/1.73m2 (vs. 77.5(54.8,104.6)ml/min/1.73m2 at baseline, p=0.212), while that in 1-2-3 Group was 97.8(68.6,130.9)ml/min/1.73m2 (vs. 79.5(52.9,108.7)ml/min/1.73m2 at baseline, p=0.002). The slope of eGFR in 1-3-5 Group was 0.7(-1.7,3.3)ml/min/1.73m2/month, while that in 1-2-3 Group was 3(1.2,5.4)ml/min/1.73m2/month, p=0.027. For side effects, two patients in 1-2-3 Group had met bronchitis during the 2nd and 3rh therapy-month respectively; in 1-3-5 Group, one patient had got glaucoma during the 2nd therapy-month and the other had happened steroid-induced diabetes mellitus during the 3rd therapy-month.
Conclusion
Our preliminary results had indicated that optimized steroid therapy had equal effect on reducing proteinuria but more significant advantage to protect against renal function deterioration in IgAN with crescents. 1-2-3 month-steroid pulse therapy had not increase the morbidity of irreversible or severe side effects.
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