Radial Immunodiffusion of Spinal Fluid: Diagnostic Value in Multiple Sclerosis

Berner, Jerome J., Ciemins, Vilnis A., and Schroeder, Edmund F., Jr.: Radial immunodiffusion of spinal fluid: Diagnostic value in multiple sclerosis. Am. J. Clin. Pathol. 58: 145–152, 1972. Spinal fluid gamma globulin (IgG) was measured by radial immunodiffusion and its percentage of cerebrospinal fluid protein (% IgG) was calculated. Increased % IgG provides a significant aid in diagnosing multiple sclerosis (MS). Of 200 patients tested, 39 were clinically diagnosed as possibly or probably having multiple sclerosis. Of these MS patients, 35.9% had marked elevations of % IgG (greater than 16% of the total protein), and 38.4% had slight elevations (11 to 16% IgG). Of the non-MS patients, fewer than 1% had marked elevations of % IgG, and 26.7% had slight elevations. In 59 patients, % IgG (% gamma globulin) was measured both by radial immunodiffusion and by electrophoresis. The results of these two methods correlated very closely, validating the immunodiffusion results. Radial immunodiffusion is a rapid and simple method of measurement of IgG levels in cerebrospinal fluid, requiring no special technic or equipment. No dialysis or pre-concentration of the spinal fluid is necessary. The sensitivity of the procedure (to 1 mg. per 100 ml. IgG) is adequate for the measurement of cerebrospinal fluid IgG.