Comparison of early IgM-enriched immunoglobulin vs polyvalent IgG administration in score-identified postcardiac surgical patients at high risk for sepsis

Study objective: To address the relevance of the IgM component in polyvalent immunoglobulins in sepsis treatment by comparison of the clinical course under polyvalent IgG vs IgGMA therapy in postcardiac surgical patients at high risk for sepsis and to reassess the prognostic validity of sequential changes in acute physiology and chronic health evaluation (APACHE II) scores during treatment. Design: Prospective, randomized clinical trial. Setting: Cardiac surgical ICU in a university hospital. Patients: Among 870 consecutive patients after elective open-heart surgery, 29 (3.3%) met the previously validated high-risk criterion (APACHE II score greater than or equal to 24 on the first postoperative day) with a mean APACHE II score-predicted mortality risk of 63%. Interventions: In addition to standard therapy, 27 of these patients were randomized to receive commercially available IV IgG (Polyglobin N, n=14, total dosage: 18 mL/kg) or IgGMA (Pentaglobin, n=13, total dosage: 15 mL/kg). Measurements and results: The two groups were comparable in baseline disease severity and concurrent therapy. The extent of score-quantified improvement in disease severity during treatment was similar in both groups (mean fall in APACHE II scores within 4 days: IgG, -6.9; IgGMA, -5.2), as were score-defined improvement rates (rate of patients with score decrease greater than or equal to 7 within 4 days: IgG, 57%; IgGMA, 54%) and in-hospital mortality (IgG, 29%; IgGMA, 31%) (all p=NS). There was a strong association between the decrease over time in APACHE II scores during therapy and prognosis (mortality rates in patients with vs without score-assessed improvement: 0% vs 67%, p=0.0002). Conclusions: IgG and IgGMA were associated with a comparable improvement in disease severity in score-identified postcardiac surgical patients at high risk for sepsis, Given the design as an efficacy rather than an equivalence study, this hypothesis derived from our results needs independent validation in larger trials. Sequential APACHE II score changes were reconfirmed as a prognostically valid quantitative measure of disease progress during sepsis therapy.