Quantitative estimation of cerebrospinal fluid globulins in multiple sclerosis. A comparison of electrophoretic and immunologic methods.

CSF samples were obtained from 44 multiple sclerosis patients during exacerbation and from 50 age and sex-matched non-multiple sclerosis controls. In an attempt ot select the most suitable test for diagnosis of multiple sclerosis, each sample was analyzed by three methods: (1) electrophoresis, (2) electroimmunodiffusion, and (3) radial immunodiffusion (RID). Electrophoresis, electroimmunodiffusion, and radial immunodiffusion yielded positive results in 50, 55, and 59 percent of the multiple sclerosis patients respectively. Electrophoresis, electroimmunodiffusion, and radial immunodiffusion yielded 10, 12, and 8 percent false positives (beyond mean +/- 1 S.D.) respectively. Thus the three tests did not differ much with regard to yield of true or false positive results. When factors such as simplicity, time and equipment involved, and the interval between the test and results are taken into account, radial immunodiffusion appears to be most suitable for an avverage CSF diagnostic laboratory. For a laboratory with special interest in multiple sclerosis, agarose gel-electrophoresis of concentrated CSF appears to be the test of choice.