Complement Profiles / Nephritic Factor
Note: Tests can be performed individually, or in a Profile package.
| C1Q | C5 | C9 | Properdin |
| C2 | C6 | Factor H | C4 Binding Protein |
| C3 | C7 | Factor I | C1 Inhibitor |
| C4 | C8 | Factor B | Nephritic Factor (optional) |
This profile is useful in the detection of inherited complement deficiencies which may predispose to lupus-like syndromes, to recurrent bacterial infection, particularly Neisserial, or to hereditary angioedema. In association with the measurement of nephritic factor, this profile aids in distinguishing acute from chronic nephritis and in identifying the three types of membranoproliferative glomerulonephritis. A nephrologist interprets all Complete Complement Profiles.
Specimen requirements 1 mL Serum, frozen.
| Factor B | Factor H | Factor I | C3 |
For distinguishing low levels of C3 resulting from undernutrition from those due to complement activation. A nephrologist interprets all Nutritional Complement Profiles.
Specimen requirements 1 mL Serum, frozen.
An autoantibody that depresses the serum level of C3 and, secondarily, other complement components. Among the hypocomplementemic glomerulonephritides, nephritic factor is absent in acute post-streptococcal glomerulonephritis and lupus nephritis. It is present in most hypocomplementemic patients with membranoproliferative glomerulonephritis and also those with partial lipodystrophy. Although the antibody may be instrumental in producing the nephritis, its level is not closely associated with the clinical course.
Specimen requirements 1 mL Serum, frozen.
