Immunoelectrophoretic studies of cerebrospinal fluid

Abstract

Immunoelectrophoresis of the cerebrospinal fluid offers better possibilities of a more refined examination of the fluid for proteins. In the present investigation, spinal fluid proteins were studied by microimmunoelectrophoresis in 46 cases of cerebral and spinal cord tumors. Examination by conventional methods (determination of total protein, colloid reactions, and paper electrophoresis) has, as a rule, proved to be of limited value in the diagnosis of such cases. The total protein was raised in half of the patients with tumor in this series, and paper electrophoresis showed no certain difference from the control series. Immuno-electrophoresis, on the other hand, showed not only the 14 proteins occurring in normal persons but also nearly always the presence of pathologic fractions. Thus, in the patients with tumor, the cerebrospinal fluid showed on the average 5 abnormal fractions; that from the 19 patients with malignant cerebral tumor, 3 to 4 pathologic proteins; and the 7 with benign cerebral tumor and the 14 with spinal cord tumor, 5 to 6 pathologic proteins. Fluid from the 4 patients with pituitary adenoma, however, showed essentially a normal picture. Increased amounts of [alpha]2-macroglobulin and [beta]1-lipoprotein were seen in 3/4 of the cases and fibrinogen in 2/3; 4 different pathologic B2-fractions were all found in anything up to 1/2 or more and an increased large molecular portion of the gamma-globulin in almost 1/2 of the patients with tumor. These findings contrast sharply with what was seen in the controls. Many of the patients with tumor and pathologic protein fractions had shown a normal paper electrophoretic pattern. No true difference was found between the findings in the patients with malignant and benign tumors, but the results tended to differ with the type of tumor, so that immunoelectrophoresis may be able to contribute to a more refined differential diagnosis of cerebral and spinal cord tumors. However, further investigation on a larger series is needed before any valid conclusion can be made in this respect. The cerebrospinal fluid from patients with cerebral or spinal cord tumor was thus found to contain more protein fractions and to a large extent also pathologic fractions (inter alia [beta]1-lipoprotein, fibrinogen, and certain [beta]2-fractions), which never occur in normal persons. Among the 46 cases of tumor, the immunoelectrophoretic pattern of the cerebrospinal fluid proteins was normal in only 4 but pathologic in the remaining 42 (91%).