Tonsillectomy Monotherapy for IgA Nephropathy: A Case Series

RATIONALE & OBJECTIVE: Studies of immunoglobulin A nephropathy (IgAN) have suggested the therapeutic benefit of simultaneously adding tonsillectomy to corticosteroid therapy. However, the efficacy of tonsillectomy monotherapy in the absence of simultaneous use of corticosteroids is unclear. STUDY DESIGN: Patients with IgAN treated with tonsillectomy monotherapy were analyzed retrospectively. Clinical parameters, including kidney function slope, were compared before and after tonsillectomy. SETTING & PARTICIPANTS: Patients with biopsy-proven IgAN who received tonsillectomy monotherapy at our hospital between 2007 and 2018. RESULTS: 20 Japanese patients with IgAN were included in this study (mean follow-up period, 135 months from initial biopsy diagnosis to tonsillectomy). All patients had been treated with renin-angiotensin-aldosterone system inhibitors. 17 patients had a history of induction therapy with corticosteroids. Mean time to tonsillectomy from termination of corticosteroid therapy was 84 months. Hematuria, proteinuria, and clinical remission were achieved in 13 of 17 (76%), 10 of 17 (59%), and 8 of 20 (40%) patients at medians of 3.0, 6.0, and 13.5 months, respectively, after tonsillectomy. The slope of the estimated glomerular filtration rate (eGFR) increased significantly during the 81-month observation period, including the periods before and after tonsillectomy (−2.59 vs 1.05 mL/min/1.73 m(2) per year; P < 0.001). The effect on eGFR slope was consistent in 11 patients with reduced GFR (eGFR < 60 mL/min/1.73 m(2)) at the time of tonsillectomy (−3.07 vs −0.39 mL/min/1.73 m(2) per year; P < 0.001). LIMITATIONS: Small sample size. Lack of a control (no-tonsillectomy) group due to the difficulty of setting the baseline time point (which corresponded to tonsillectomy in our sample). Potential exclusion of patients with the most severe disease who are likely to receive corticosteroids. Lack of generalizability to patients in other countries. CONCLUSIONS: Tonsillectomy monotherapy may prevent kidney function decline in some patients with IgAN with kidney disease that has been progressive despite long-term application of conventional therapies.