Definitions for the levels of evidence (I–IV) can be found at the end of the "Major Recommendations" field.
Guidelines
No recommendation possible based on Level I or II evidence
Suggestions for Clinical Care
(Suggestions are based on Level III and IV evidence)
Numerous retrospective cohort studies and case reports have suggested that tonsillectomy may reduce proteinuria and serum total immunoglobulin A (IgA) concentration, decrease episodes of macroscopic haematuria and slow progression to end-stage kidney disease (ESKD) in patients with tonsillitis. In retrospective series, tonsillectomy has been associated with improved renal outcome in patients with IgA nephropathy, over and above standard therapy. However, these results have not been consistent in all studies. Moreover, these results are confounded by indication making the true role of tonsillectomy difficult to interpret.
- One study examined renal outcomes in 237 patients with IgA nephropathy (aged 31 ± 14 years, mean ± SD) who had been followed-up for at least 6 months (follow-up periods, 62.3 ± 45.5 months). On univariate analysis, tonsillectomy was the only significant treatment that contributes to the maintenance of normal renal function. In addition, urinary abnormalities disappeared at a significantly higher frequency when patients were treated by tonsillectomy. However, the severity of baseline renal disease was not equivalent in all groups and the protective effect of tonsillectomy was eliminated after adjusting for other baseline variables.
- Another study retrospectively reviewed data on renal outcome in 55 patients with IgA nephropathy. In this study, there was no significant correlation between tonsillectomy and ESKD after 3.4 ± 4 years of follow-up, when adjusting for baseline risk factors.
- Another study retrospectively reviewed data from over 15 years in 118 patients with idiopathic IgA nephropathy, including 48 patients who had undergone tonsillectomy and 70 who had not. After adjusting for baseline risk factors, only five (10.4%) of patients (n = 48) who had undergone tonsillectomy entered dialysis, whereas 18 (25.7%) of 70 patients who had not undergone tonsillectomy required dialysis (P = 0.04). Cox regression analysis showed that the relative risk for terminal renal failure in patients following tonsillectomy was lower compared to control patients (hazard ratio 0.22, 95%CI: 0.06 to 0.76, P = 0.0164).
- Another study reviewed 50 patients with IgA nephropathy and chronic tonsillitis, including 35 patients with and 15 without tonsillectomy. In patients with a serum creatinine level of < 1.4 mg/dL, renal function remained normal in all subjects with tonsillectomy but worsened in 3 of 13 patients without tonsillectomy. There was no effect seen in patients with a serum creatinine level of > 1.4 mg/dL at the time of renal biopsy. They proposed that tonsillectomy might have a role for patients with IgA nephropathy complicated by tonsillitis when the operation was performed before deterioration of renal function.
- Another study followed 75 patients with biopsy-proven IgA nephropathy for an average of 12.2 years, including 35 patients who had undergone tonsillectomy. Although the level of microhaematuria 6 months after tonsillectomy was similar to before the procedure, tonsillectomy stopped gross haematuria appearing in the acute exacerbation of the disease in more than two-thirds of patients. ESKD was detected only in 4 of 35 patients 10 years after tonsillectomy, compared to 8 of 40 patients from a non-tonsillectomised control group with IgA nephropathy.
- Another study conducted a retrospective review of the renal outcome in 329 patients with IgA nephropathy, with an observation period longer than 36 months (82.3 ± 38.2 months). Their results showed that there were no significant differences between the tonsillectomy and nontonsillectomy groups regarding the incidence of progressive renal functional loss (defined as a 50% increase in baseline serum creatinine). However, tonsillectomy had a significant impact on clinical remission by multivariate Cox regression analysis.
- Another study retrospectively reviewed 70 patients with IgA nephropathy and renal impairment (serum creatinine > 1.5 mg/dL). Steroid pulse with tonsillectomy, and conventional steroid and supportive therapy were performed in 30, 25 and 15 patients, respectively. The incidence of ESKD 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 to 2 mg/dL, but no statistical difference was observed at a level of > 2 mg/dL. Like the findings of a previous study, the authors concluded that steroid pulse therapy combined with tonsillectomy may be more effective than conventional steroid therapy in patients without moderate to severe renal impairment.
- Another study performed a 10-year retrospective case-control study of 71 patients with IgA nephropathy to evaluate the long-term effects and prognostic factors associated with tonsillectomy. A total of 41 patients who had undergone tonsillectomy were compared with 30 patients who had not. After over 12 years of follow-up, the clinical remission rate was 24% in the tonsillectomy group and 13.3% in those not receiving tonsillectomy. Similarly, renal survival was higher in patients who had undergone tonsillectomy.
- Another study reviewed long-term renal survival in 46 patients who had undergone tonsillectomy, and 74 patients with IgA nephropathy who had not. Five (10.9%) of the tonsillectomy group reached ESKD whereas 19 (25.8%) of the non-tonsillectomy group did.
In summary, tonsillectomy could reduce proteinuria and haematuria in those patients without moderate to severe renal impairment. These studies are retrospective and potentially confounded by indication, making the clinical significance of this intervention difficult to interpret.
Definitions:
Levels of Evidence
Level I: Evidence obtained from a systematic review of all relevant randomized controlled trials (RCTs)
Level II: Evidence obtained from at least one properly designed RCT
Level III: Evidence obtained from well-designed pseudo-randomized controlled trials (alternate allocation or some other method); comparative studies with concurrent controls and allocation not randomized, cohort studies, case-control studies, interrupted time series with a control group; comparative studies with historical control, two or more single arm studies, interrupted time series without a parallel control group
Level IV: Evidence obtained from case series, either post-test or pretest/post-test
