Intravenous Immunoglobulin in the Therapeutic Armamentarium of Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis

Prepared from the plasma of thousands of blood donors, therapeutic intravenous immunoglobulin (IVIg) mostly consists of human polyspecific immunoglobulin G (IgG). The use of IVIg in systemic lupus erythematosus (SLE) is still considered experimental without any clear indications. The purpose of this systematic review is, therefore, to evaluate the available evidence to determine the therapeutic role of IVIg in SLE. A comprehensive, computerised search was performed in the MEDLINE (Pubmed), Scopus, EMBASE, and Cochrane controlled trials. The study eligibility criteria were randomized controlled trials, and prospective and retrospective observational studies that examined the efficacy of IVIg in adult patients with SLE who were considered the participants. IVIg therapy was the mode of intervention in these patients. Data abstracted included the study design, study population, changes in the disease activity scores (Systemic Lupus Erythematosus Disease Activity Index, Systemic Lupus Activity Measure, and Lupus Activity Index-Pregnancy), steroid dose, complement levels, autoantibodies, and renal function. Thereafter, data analysis established statistical procedures for meta-analysis. Thirteen studies (including 3 controlled and 10 observational) were eligible for inclusion. There was significant reduction in the SLE disease activity scores with IVIg therapy with a standard mean difference of 0.584 (P = 0.002, 95% confidence interval [CI] 0.221-0.947). In terms of rise in complement levels, the response rate was 30.9% (P = 0.001, 95 CI 22.1-41.3). The effects of IVIg on other clinical outcome measures including anti-double-stranded DNA, antinuclear antibody, average steroid dose, and renal function could not be determined because of the limited numbers of trials. The limitations of this review were lack of well-designed controlled trials with adequate sample size on the use of IVIg in SLE. In conclusion, the use of IVIg is associated with significant reduction in SLE disease activity and improvement in complement levels.