Comparative Tests for Occult Blood in Gastric Contents and Feces, with Especial Reference to the Benzedin Test

JOHN W. DEWIS
1907 Boston Medical and Surgical Journal  
But, as shown below, we know that the guaiac test is more delicate than indicated in this table. Schmilinsky (p. 214!5t) gives a simple method of obtaining the blood spectrum by means of the hematoporphyrin method : a number of drops of stomach contents or feces, well mixed with water, are slowly added to a few cubic centimeters of concentrated sulphuric acid. If the solution is placed in a glass dish with plain parallel walls the spectrum can be easily recognized. The test is quite sharp and
more » ... s quite sharp and quickly carried out; if it is negative the guaiac test, which is more delicate, must be applied, so nothing is gained by its use. t The principle, of course, is that of Hoppo-Seyler, and tho sides of the vessel (known as the honiutiuomctor) aro 1 cm. apart.
doi:10.1056/nejm190708081570601 fatcat:gz2dn6vp7jfsdnibiisl3xvrty