MP166CLINICAL OUTCOMES OF TONSILLECTOMY AND STEROID PULSE THERAPY FOR PATIENTS WITH IgA NEPHROPATHY

Abstract

Introduction and Aims: Chronic glomerulonephritis (CGN) including IgA nephropathy (IgAN) had been the most common cause of end‐stage renal disease (ESRD) in Japan until 1997, but diabetic kidney disease has become the primary cause of ESRD in 1998, and CGN is decreasing in both ratio and number as a cause of ESRD. This phenomenon may be partly explained as the result of that tonsillectomy and steroid pulse therapy has widely been used to treat IgAN, however, its outcome has not been fully elucidated. The purpose of this study is to elucidate the effects of tonsillectomy and steroid pulse study on the urinary protein and estimated GFR (eGFR) of IgAN patients. Methods: 31 patients with biposy‐proven IgAN, who were diagnosed between April 2013 and March 2015 in our center, were enrolled in this study. 20 patients were treated by tonsillectomy and steroid pulse therapy (group 1), other 5 patients were treated by tonsillectomy only (group 2), and remaining 6 patients were treated by neither of them (group 3). Estimated GFR (eGFR) was calculated by using the revised equations for estimated GFR by Japanese Society of Nephrology. Group 1 was divided into two subgroups according to their eGFRs: group 1a (n = 15); baseline eGFR ≥ 60 (mL/min.1.73 m2), group 1b (n = 5); 60 > baseline eGFR ≥ 30. Urinary protein/ creatinine ratio (UP:UC) was also calculated. Both eGFR and UP:UC were measured at three different occasions in each patient before and 6 months after the treatment, and their average were used for the investigation. Results: In group 1, baseline UP:UC was 0.99±0.77 (g/gCr) and which was significantly decreased to 0.23±0.24 in 6‐months after the treatment (p < 0.05), and eGFR was not significantly changed (77.3±23.2 to 77.8±20.8 mL/min.1.73 m2). In group 2, baseline UP:UC and eGFR were 0.36±0.19 and 80.3±20.3, and they became to 0.28±0.27 and 73.7±16.2 in 6 months after treatment, respectively, and in group 3, baseline UP:UC and eGFR were 1.80±1.34 and 61.4±20.3, and they became to 1.33 ±1.46 and 68.4±16.2 in 6 months after treatment, respectively (statistic analysis was not performed because the numbers of patients were small). In group 1a, baseline UP:UC and eGFR were 0.81±0.67 and 88.6±12.6, and they changed to 0.25±0.26 (p < 0.05) and 87.9±11.4 (n.s.), and in group 1b, baseline UP:UC and eGFR were 1.42±0.95 and 43.4 ±0.93, and they changed to 0.19±0.19 (p < 0.05) and 47.5±11.4 (n.s.). The major adverse effects of the tonsillectomy and steroid pulse therapy were postoperative pain in almost all patients which usually lasts in several days and haemorrhage in 1 case. Conclusions: As this study is an observational study and is not a randomised controlled study, we cannot conclude which treatment is better, nevertheless, tonsillectomy and steroid pulse therapy seems to be tolerable and enough effective in reducing urinary protein excretion. Urinary protein reduction is proved to be associated with better renal outcome in many glomerular diseases including IgAN, therefore tonsillectomy and steroid pulse therapy is expected to improve the outcome of IgAN patients, even in the advanced cases with low eGFR.