Ten studies were included for review (n=645): eight prospective RCTs (n=492), one prospective matched controls (n=87) and one retrospective case-control study (n=66).
Overall Mortality:
Treatment with IgM-enriched IVIG was associated with a significant reduction in mortality (OR= 0.35, 95% CI: 0.23, 0.54, p<0.00001) compared to placebo or no intervention. There was no evidence of statistical heterogeneity. The authors reported that when non-randomised studies were excluded from the model, no significant change in effect size was found.
One RCT including only patients with Gram-negative sepsis showed significant reduction in mortality compared to controls with no intervention (4% versus 32%, p=0.012). Subgroup analysis of patients with Gram-negative sepsis was possible in two studies. Both found a greater reduction in mortality rates in the treatment groups compared to controls (5.9% versus 15.8% in controls receiving 10% dextran and 11.8% versus 50% in no intervention controls, p<0.02).
Severe Sepsis or Septic Shock:
Two RCTs focusing exclusively on patients with severe sepsis or septic shock found a significant reduction in mortality in the treatment group compared to the control groups (p=0.012 and p<0.01). Subgroup analysis of patients with severe sepsis was carried out for two further studies. One retrospective case-control study found a significant benefit of treatment in patients with severe sepsis when compared to controls (p=0.04), whereas one RCT found no significant benefit with treatment for patients with severe sepsis.