LEVEL OF PLASMA PREKALLIKREIN AND ITS INHIBITORS IN REACTORS AND NONREACTORS DURING INTRAVENOUS ENHANCEMENT WITH CONTRAST MEDIA

Complex contact activation systems may play a major role in the side effects of i.v. contrast media (CM). This is why quantitative measurements of several factors (plasma prekallikrein, hematocrit (hct), α-2-macroglobulin, α-1-antitrypsin, and C1-esterase inhibitor) were determined prior to and following the injection of CM during body CT examination in 5 patient groups, each (n = 10) receiving one of 5 different CM, including ioxaglate, meglumine iodamide, metrizamide, iohexol, and meglumine diatrizoate. The initial plasma prekallikrein level was available from 45 patients and was statistically lower in reactors (mean 90.6 μmol TAMe/ml/h; n = 13) than in nonreactors (mean 107 μmol TAMe/ml/h; n = 32) (p = 0.006), but there was no statistically significant difference in the decrease of plasma prekallikrein before and at 5 min after the injection for those 2 groups. The initial plasma C1-esterase inhibitor level was lower in reactors, while the plasma α-2-macroglobulin level was higher in that group than in...