The thymol turbidity and cephalin-cholesterol tests, euglobulin, albumin-globulin ratio and serology in leprosy.

During the course of experimental work on leprous patients in Hawaii, Dr. Eric Fennel observed a relationship between the thymol turbidity and cephalin-ehoiesteroi tests, the albumin: globulin ratio and the degree of skin involvement in the cases he studied. He made observations on 25 cases and included some of his fi ndings in a report on the thymol turbidity test (4), but he felt that they were insufficient to justify more extended publication. In a personal interview with him in 1947 it was agreed that I should repeat that work on a larger group of patients. While doing so, the opportunity was taken to compare these tests with the euglobulin of the serum as well as the serology. Experience has shown that various serum· turbidity and flocculation reactions used in the clinical laboratory respond different1y with sera from patients with different diseases. It was hoped originally that one or the other of these tests would be specific fOT liver diseases. but it has since been shown that positive reactions are produced primarily when the concentration of some particular protein fraction of the serum is greater than normal. The thymol turbidity test was first described by MacLagan (8) in 1944 as an index of liver function. He believed that the thymol turbidity is due to a globulin-thymol-lipid complex. and that the test gives essentially the same results as the colloidal gold procedure which has been used in the study of liver disease. The earlier studies of Hanger (6) likewise implicated a globulin -that is, gamma globulin-as the important factor in the cephalin-cholesterol flocculation. Subsequently, Hanger and coworkers (9) described evidence indicating that that there must be an alteration in the character of the serum albumin, together with an increased globulin, before flocculation will take place. 1t is evident that the underlying mechanism of the two tests is not identical. With other associates Hanger (10), using electro-