Determination of CSF proteins by a simple and rapid immunonephelometric method.

A simple, fast and reliable immunonephelometric (I-NEPH) method has been worked out for the determination of CSF proteins. A good quality and low price I-NEPH apparatus was used. The results were obtained from regression lines, constructed from various parts of the calibration curve, calculated by using a simple pocket calculator. Ultrasound was found to be a simple and effective cleaning technique for nephelometry. The method was used for determining concentrations of albumin, IgG, IgA, IgM and the ratio of the light kappa and lambda chains in CSF and serum from 15 control cases, 11 MS patients, and three patients with plasma cell dyscrasias. The I-NEPH method was found to be a valuable complement to high separation techniques including especially isoelectric focusing used for CSF examinations, e.g., for evaluating influence of serum protein composition and degree of barrier damage. An increased kappa-lambda ratio was observed in some of the patients with MS in accordance with previous investigations but was normal in four of the nine MS cases where the ratio was examined.