Intravenous immunoglobulin (IVIg) is an anti-inflammatory drug with an unclear role in the treatment of patients with lupus nephritis (LN). This systematic review evaluates the evidence for IVIg in the care of patients with LN.

A systematic search was done in the PubMed, EMBASE, BVS and OVID databases - All EBM Reviews following the PRISMA methodology (registration in PROSPERO CRD42021236662). The variables were extracted: indications for use, dosage, partial or complete response, adverse reactions, initiation of renal replacement therapy, reduction of proteinuria, and mortality. The quality assessment was done with the "The Joanna Briggs Institute (JBI) Critical Appraisal tools for use in Systematic Reviews Checklist". In addition, synthesis reports were prepared through the Synthesis Without Meta-analysis - SWiM guide.

A total of 2328 articles were obtained (28 were considered for inclusion). When the studies were evaluated, IVIg therapy was found to be between 60% to 70% effective (except for patients with class V LN) with overall responses (complete + partial) even for patients who are refractory to first line treatment. Normalization (<0.5 g) of nephrotic proteinuria occurred in 24% of cases with infrequent adverse events and a mortality plus dialysis composite of 11.5% and 24.1% (most representative study).

In patients with LN refractory to conventional treatment or co-infection situations, the reported data seem to demonstrate effectiveness of IVIg therapy. There are few adverse reactions and caution is exercised when using it on patients with class V NL. However, given the lack of controlled studies with long-term follow-up, these data should be interpreted cautiously thus encouraging the development of high-quality RCTs.