[Determination of pyrogens: comparison of different methods] [Article in German]

Abstract

Pyrogens are a group of chemically diverse substances that cause fever and shock in severe cases. The most important pyrogenic substances in pharmaceutical industry are bacterial endotoxins. Bacterial endotoxins are part of the cell wall of gram negative bacteria. There are two methods of detection: the Pyrogen test is based upon the measurement of body temperature of rabbits before and after injection of the specimen, the LAL-Test is based upon the clotting reaction of an enzyme complex of cells of the horseshoe crab together with bacterial endotoxins (in vitro test). Advantages and disadvantages of the two tests have been compared. Although the LAL-Test is widely used a total replacement of the Pyrogen test still is not possible since on the one hand the LAL-Test will only detect bacterial endotoxins and on the other hand not all specimen can be tested with the LAL-Test because of interference with the test. An example has been given by comparing the test results of three related cephalosporins in the Pyrogen test and different methods of the LAL-Test (gel clot, turbidimetric kinetic, chromogenic kinetic).