Cohort study of advanced IgA nephropathy: efficacy and limitations of corticosteroids with tonsillectomy.
BACKGROUND
Elevated serum creatinine is associated with poor outcome in IgA nephropathy (IgAN). The efficacy and limitations of corticosteroids in advanced IgAN (Cr >or=1.5 mg/dl), however, remains controversial.


METHODS
We retrospectively investigated 70 patients with advanced IgAN (Cr >or=1.5 mg/dl) classified into three groups according to their treatment regimens, that is, steroid pulse with tonsillectomy, conventional steroid, and supportive therapy. We evaluated the three groups to elucidate predictors for the endpoints ESRF and doubled serum creatinine from baseline.


RESULTS
Steroid pulse with tonsillectomy, conventional steroid and supportive therapy were performed in 30, 25 and 15 patients, respectively. During the mean follow-up period of 70.3 (12-137) months, 41.4% of patients reached ESRF (13.3 vs. 56.0 vs. 73.3%, p < 0.001) and 45.7% doubled serum creatinine from baseline (16.7 vs. 64.0 vs. 73.3%, p < 0.001). The incidence of ESRF in the patients treated by steroid pulse with tonsillectomy was significantly lower than the incidences in the patients treated by conventional steroid and supportive therapy at a baseline creatinine level of 1.5-2 mg/dl, but no statistical difference was observed at a level of >2 mg/dl. The Kaplan-Meier estimated probability of renal survival without ESRF was 89.2, 74.1 and 72.2% at 5 years and 82.8, 51.0 and 45.1% at 8 years, respectively (p = 0.017). The predictors for ESRF, identified in a Cox proportional hazards model, were baseline serum creatinine (p < 0.001) and interstitial infiltrate (p = 0.003). Steroid pulse with tonsillectomy also had a protective effect on the risk of reaching ESRF (p = 0.013). By target cross-stratification, the patients with baseline creatinine of 1.5-2 mg/dl who underwent steroid pulse with tonsillectomy showed a better renal survival rate than the others (p < 0.001).


CONCLUSIONS
Steroid pulse therapy combined with tonsillectomy may be more effective than conventional steroid therapy in patients with a baseline creatinine level of <or=2 mg/dl.
Sato
Mitsuhiro
M
Department of Nephrology, Sendai Shakaihoken Hospital, Sendai, Japan. darksea@eurus.dti.ne.jp
Hotta
Osamu
O
Tomioka
Sachiko
S
Horigome
Ikuo
I
Chiba
Shigemi
S
Miyazaki
Mariko
M
Noshiro
Hiroo
H
Taguma
Yoshio
Y
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D015331:Cohort Studies; D003131:Combined Modality Therapy; D003404:Creatinine / Q000097:blood; D005260:Female; D005922:Glomerulonephritis, IGA / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000601:surgery*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000209:etiology; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D020551:Pulse Therapy, Drug; D012189:Retrospective Studies; D014068:Tonsillectomy; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones; D003404:Creatinine