[Prognostic factors of IgA nephropathy after tonsillectomy]

Tonsillectomy is one of the prevailing treatments for IgA nephropathy. This retrospective study aimed to elucidate prognostic factors for the postoperative kidney function of tonsillectomized patients with IgA nephropathy. Forty consecutive patients with IgA nephropathy who underwent tonsillectomy in our department between 1999 and 2008 were enrolled. They were 21 men and 19 women with ages ranging 14-52 years with an average age of 25.5 years. The patients were classified into remission and non-remission groups based on their kidney function assessed 1 year after surgery according to the clinical guidelines for IgA nephropathy of the Japanese Society of Nephrology. Patients' profiles and preoperative physical findings/laboratory data in the remission group were then compared with those in the non-remission group. The remission and non-remission groups included 13 and 27 patients, respectively. The remission group showed a significantly shorter interval between onset to surgery (2.3 +/- 2.1 vs. 5.0 +/- 6.7 years; p = 0.032), a lower diastolic blood pressure (66 +/- 13 vs. 75 +/- 17 mmHg; p = 0.040), a higher level of serum total protein (7.6 +/- 0.5 vs. 7.0 +/- 0.7 mg/dl; p = 0.015), and a higher degree of tonsillar hypertrophy (I degrees: II degrees: III degrees = 5 : 8: 0 vs. 21 : 6 : 0; p = 0.033) in comparison with the non-remission group. Multiple logistic regression analysis also revealed that patients with a higher level of serum total protein and those with a higher degree of tonsillar hypertrophy were more likely to recover. We should carefully consider these prognostic factors when indicating tonsillectomy for the treatment of IgA nephropathy.