Novel C3 Nephritic Factor Activity in the Glomerulonephritis of Staphylococcal Endocarditis

摘要

A case of glomerulonephritis complicating staphylococcal endocarditis is presented. Hypo-complementaemia and a C3-activating factor in the serum suggested that the patient might have mesangiocapillary glomerulonephritis in association with C3-nephritic factor. Renal biopsy showed that this was not so and further examination of the serum factor showed that it differed from classical C3-nephritic factor because it was not an immunoglobulin.It is postulated that complement activation and glomerulonephritis in staphylococcal endocarditis may be the direct result of a bacterial product. A substance in the serum which activates C3 should be confirmed to be an immunoglobulin before the presence of classical C3-nephritic factor is assumed.