An "evidence-based" survey of therapeutic options for IgA nephropathy: assessment and criticism

Immunoglobulin A (IgA) nephropathy is a worldwide disease that causes end-stage renal failure in 15% to 20% of patients within 10 years of the apparent onset of disease and in 30% to 40% of individuals within 20 years. Severity of renal lesions, serum creatinine level, and severe proteinuria are adverse prognostic indicators. No specific treatment has been established, but several approaches have been experimented.

We reviewed the literature and evaluated the quality of published randomized trials using standard methods and the quality of their reporting according to the revised version of the Consolidated Standards for Reporting Trials Statement. Meta-analyses of randomized trials on the efficacy of steroid treatment, cytotoxic agents, and fish oils on the outcome of renal function and daily proteinuria in patients with IgA nephropathy were performed.

Only 10 randomized trials were available and included in the review. Their quality was very poor, and a limited amount of data was reported. Cytotoxic agents seem beneficial on both renal function (relative risk, 0.38; 95% confidence interval [CI], 0.22 to 0.66) and daily proteinuria (weighted mean difference [WMD], -1.16; 95% CI, -2.18 to -0.14) in patients with moderate to severe renal damage, steroids act mainly on proteinuria (WMD, -0.50; 95% CI, -0.78 to -0.21), and fish oils do not imply a particular benefit. This statement is based on the very limited and poor available published evidence.

Only a few randomized trials, of low quality and inadequately reported, are available relating to treatment of IgA nephropathy. More properly designed and reported trials are necessary to reach a definitive assessment of this matter.