COMPLEMENT IN INFECTIOUS DISEASE IN MAN 1

Abstract

A study of hemolytic complement and the components of complement in the sera of 248 patients with infectious diseases showed a distribution of C titers significantly different from that in the sera of 40 normal persons. The occurrence of a low titer (50 units per ml.) were most frequently observed in cases of erysipelas and scarlet fever. In cases of pneumonia, unusual deviations from the normal titer were observed but these deviations were sometimes toward high and sometimes toward low titers. In those cases showing a subnormal titer there was a marked diminution or disappearance of the component C[image]4 and occasionally a diminution of C[image]2 and C[image]l. In cases where an abnormally high titer occurred, all 4 components seemed to participate in the increase. The prognosis was found to be grave in most of the cases where low C[image] titer persisted. The fatality rate among the cases with low C titer was 33.3% as compared with 5% for the entire group of patients. No apparent relationship between complement and white blood cell count or body temp. was detected. The occurrence of a high protein content in a serum appeared to dispose it toward a high C[image] titer and a low protein content to dispose it toward a low titer.