Effect of thermal injury and subsequent therapy on serum protein concentrations

Abstract

We have measured the quantities of serum IgG, IgA, IgM, complement C′3, and alpha 2 macroglobulin in 43 patients divided into four groups according to severity of injury and comorbidity factors. We have been careful to select patients not receiving drugs which are known to alter serum protein production. We have compared serum protein concentrations 1 day, and 1, 2, 3 and 4 weeks post burn with age- and sex-adjusted normal means, and correlated serum protein changes with the occurrence of serum immunosuppressive activity, as measured by the effect of serum additions on the PHA responses of normal human lymphocytes in vitro. In general, it appears that IgG and IgA concentrations are initially depressed followed by elevated quantities circulating 2–3 weeks post burn. IgM and C′3 concentrations were elevated throughout the period of study with no initial depression, while alpha 2 macroglobulin concentrations were depressed throughout the period of study. There was no correlation between the occurrence of serum mediated immunosuppression and serum protein concentrations. Significantly, Ig concentrations were found to be normal or supranormal at times of maximum serum suppressive activity. The implications of these changes in serum protein concentrations are discussed.