#3045 EFFICACY AND SAFETY OF MONTHLY-STEROID PULSE THERAPY AND TONSILLECTOMY IN PATIENTS WITH IGA NEPHROPATHY
Authors: Fujii Takayuki , Terasaki Noriko , Matsunaga Takahiro , Koshizaka Junya , Morimoto Mayu , Yamauchi Nobuaki , Tanaka Hiroaki , Suzuki Satoshi 
Published: June 2023

Abstract

Background and Aims
In Japan, tonsillectomy and corticosteroid therapy is widely performed in patients with IgA nephropathy, to improve kidney outcomes and reduce proteinuria and hematuria. Over the last decade, patients with IgA nephropathy with ≥1g/day of proteinuria are treated with corticosteroid globally. However, after the results of the STOP-IGA and TESTING trials regarding efficacy and safety, the KDIGO 2021 clinical practice guideline suggest the use of immunosuppressive drugs only in patients who remain at high-risk for progressive chronic kidney disease despite maximal supportive care, after considering the risks and benefits. The TESTING trial showed that even in the reduced-dose group, severe adverse events occurred. In order to reduce steroid-induced toxicity, we administrated steroid pulse therapy monthly for 3 consecutive months and tonsillectomy without post-treatment. Thereafter, the effects and adverse events were evaluated.

Method
Forty-two patients diagnosed with IgA nephropathy on biopsy at our hospital, with ≥0.3g/day of proteinuria, and who had undergone tonsillectomy and steroid pulse therapy were included in the study. Of these patients, 16 were treated with three months of consecutive steroid pulse therapy without follow-up steroid administration (MSP); the remaining patients were administrated the conventional steroid pulse therapy (SP), including modified Pozzi's (Lancet 1999) and Hotta's (AJKD 2001) regimens. We evaluated and compared the time to proteinuria remission and both hematuria and proteinuria remission between the two groups using Kaplan-Meier curve and log-rank test. Remission of proteinuria was defined as three consecutive urinary protein results of &lt;0.3g/day over 6 months, and that of hematuria was defined as three consecutive results of &lt;5 RBCs/high-power field in the urinary sediment. In addition to efficacy, we compared the incidence rates of adverse events between the two groups.

Results
There were no significant differences in the age, sex, time to diagnosis, histopathological findings according to the Oxford classification, or RAS inhibitor use between the MSP and SP groups. The eGFR(ml/min/1.73m2) was 81.3 and 78.5, and the urinary protein excretion (g/day) was 1.01 and 1.18, in the MSP and SP groups, respectively. The proteinuria remission rates in the MSP and SP groups were 81% and 69% after one year and 94% and 81% after two years, respectively, with no significant difference. The remission rates of both hematuria and proteinuria were 47% and 46% after one year and 77% and58% after two years, respectively, with no significant differences. The incident rates of adverse events, including diabetes and infections, was 13% and 54% in the MSP and SP groups, respectively, and was significantly lower in the MSP group (p = 0.005).

Conclusion
Tonsillectomy with monthly steroid pulse therapy was effective and safer than the conventional steroid pulse therapy in patients with IgA nephropathy.