Rapid determination of cold insoluble globulin by laser nephelometry. Application in patients receiving preoperative total parenteral nutrition.

A simple and rapid method for determining plasma fibronectin or cold insoluble globulin (CIG) based on immunochemical precipitation and laser nephelometry is described. The coefficient of variation within the series was 4.2% and between the series 9.1%. The mean value for 37 control subjects was 100.1% +/- 20.6 (SD). Nineteen patients with gastrointestinal carcinoma or Crohn's disease were investigated on admission. The mean value of their plasma CIG was 104.7 +/- 26.9 (SD), which was not statistically different from the control subjects. Twelve of the patients received total parenteral nutrition (TPN) during the two preoperative weeks. The concentration of CIG was significantly increased after one and two weeks of TPN compared to the initial value. Six out of seven patients that postoperatively showed signs of infection had CIG values below 90% on admission. Of several other plasma proteins determined on admission, only a statistically significantly negative relationship to transferrin was found. CIG did not significantly relate either to the acute phase reactants, haptoglobin and orosomucoid, or to visceral proteins albumin, choline esterase or prealbumin.