Spinal-fluid gamma-globulin and multiple sclerosis.

It has been known for more than 20 years that the gamma globulin content of the spinal fluid is often disproportionately increased in multiple sclerosis (Kabat, Landow, and Moore, 1942). This finding has been confirmed by a variety of tech niques and is now of established value in the diagnosis of multiple sclerosis. However, the quantitative estimation of spinal-fluid gamma-globulin is not widely available as a routine diagnostic test, presumably because the original electrophoresis and immunochemical techniques are difficult and laborious. Simpler methods for estimating spinal-fluid gamma-globulin were introduced following Kunkel's (1947) demonstration that zinc sulphate precipitates gamma-globulin selectively from dilute serum (Donovan, Foley, and Moloney, 1951 ; Roboz, Hess, and Forster, 1953 ; Papadopoulos, Hess, O'Doherty, and McLane, 1959), and it has been claimed that such methods are as accurate as aids to the diagnosis of multiple sclerosis as are electrophoresis and immunochemical methods (Foster and Horn, 1962 ; Tourtellotte, 1963 ; Castaigne, Cambier, and Schuller, 1965). A simple zinc sulphate method for estimating spinal-fluid gamma-globulin has been in routine use in the Royal Victoria Infirmary, Newcastle upon Tyne, for the past five years. The following report outlines the results obtained during this period.