Complement and Its Component Fractions in Cerebrospinal Fluid in Inflammatory Cerebrospinal Diseases.

It is generally agreed that normal spinal fluid is entirely devoid of complement, but the reports of its presence in the spinal fluid in cerebrospinal diseases are contradictory. Complement was found in the spinal fluid of all cases of meningococcus meningitis by Ward and Fothergill (1), but was reported to be absent in the same diseases by others (24). Ward et al. (1, 5) found complement to be absent in the spinal fluid of cases of influenzal meningitis. Hauptmann (6) reported that complement may be found in the spinal fluid of tuberculous meningitis, but not in meningitis of other types. An early report (7) indicated that complement was absent from spinal fluids in various pathological conditions of the central nervous system, including cases with signs of meningitis. Present evidence indicates that complement activity results from the action of at least four components, more or less loosely combined, and present in different concentrations (8-10). When one or more of these components are missing, there is an absence of complement activity. Since the component in least concentration determines the titer of complement activity (8-10), evidence of such activity will be found when that component is present in minute amounts, and negative results will be obtained when it is entirely absent, although the other three components may be present in considerable quantities. This makes it possible to titrate each of the four components of complement independently by the addition of the other three components in excess. In accordance with the terminology adopted by Pillemer and Ecker (11) and Bier et al. (9) for complement and its components, whole complement as demonstrated by hemolytic activity is designated as C' and the four components are designated as C'1, C'2, C'3 and C'4. This evidence has been collected from studies of complement activity in blood serum (810). There are no reports of similar studies in human cerebrospinal fluid. MATERIALS AND METHODS