In vitro effect of intravenous immunoglobulin supplementation on serum opsonic activity in tracheostomised patients.

An in vitro study of the effect of immunoglobulins (mainly IgG) on opsonophagocytic activity of polymorphs was carried out in 17 tracheostomised patients admitted in medical intensive care unit of our hospital. The opsonic and phagocytic activities were tested against Staphylococcus aureus by modified polymorphonuclear leucocyte overlay method; and serum IgG and serum IgM levels were estimated by single radial immunodiffusion technique. As compared to healthy volunteers, opsonophagocytic activity was significantly lower in tracheostomised patients. However, this activity improved markedly after immunoglobulin supplementation (P less than 0.01). The same degree of enhancement was also observed in normal controls.