Van den Bergh Reaction of Bilirubin in Xanthochromic Cerebrospinal Fluid

Abstract

It is well recognized that in blood serum normal bilirubin within certain limits of concentration gives a delayed reaction in the Van den Bergh test (diazo reaction). This type of reaction differs from the prompt reaction obtained with isolated bilirubin and that encountered in a variety of pathological states. In attempting to explain this difference numerous factors have been considered. The most thoroughly studied of these concern changes in chemical constitution of the bilirubin molecule, changes in adsorption of the bilirubin by blood colloids and bilirubin concentration. None of the explanations has been universally accepted. An important reason for the lack of conclusive experiments which would solve this problem is that much of the work has been done on blood where it is practically impossible to control all of the factors properly. Not only are the colloids in relatively high concentration, but also the influence of the liver can not be excluded entirely even in dehepatized animals. It would seem that much information could be gained from a study of the phenomena under less complicated conditions. Such conditions are found in the cerebrospinal fluid. Influence of the liver can be excluded almost entirely and the colloids (proteins) are present normally in such low concentration as to be practically negligible. Even the concentration present under extreme pathological conditions is very low when compared with that normally present in the blood. Soon after a small quantity of blood is introduced into the ventricles of the brain or into the subarachnoid space the cerebrospinal fluid becomes xanthochromic. Obviously the color is produced by a pigment derived from hemoglobin and is undoubtedly identical with bilirubin formed elsewhere in the body including that normally present in the blood serum.