Test Overview
Turbidmetric
Follow lupus patient's response to therapy; screen for genetic complement component deficiency. Detection of deficiencies and decreased levels of serum complement as seen in renal disease (acute glomerulonephritis, membranoproliferative glomerulonephritis, renal allograft rejection), collagen disease (active systemic lupus erythematosus (SLE), 10% of patients with rheumatoid arthritis (RA), hemolytic anemia (paroxysmal cold hemoglobinuria), hypersensitivity and autoimmune diseases (acute serum sickness, acute vasculitis) as well as subacute bacterial endocarditis, mixed cryoglobulinemia, and advanced hepatic cirrhosis.
41 - 95 U/mL
Levels are affected by patient's age, stage and activity of disease, treatment and genetic factors. A single normal result may be misleading; longitudinal studies are clinically more helpful.
Test Details
8 hours
- CAE Total Complement
- CH50
- Functional Complement Assay
- Total Active Complement
- Total Hemolytic Complement
- CAE TOTAL COMPLEMENT (CH50)
Specimen Requirements
Collect specimen in a red top or SST tube. Allow the specimen to clot at room temperature for 30 to 60 minutes (65 minutes maximum). Centrifuge and aliquot serum into a plastic vial. Freeze immediately. If specimen processing equipment is not available, the patient should have the specimen collected at an MLabs Blood Drawing station.
Place on ice immediately or process according to Offsite Collection Instructions.
Additional Information
Measures biologically active and functional classical complement pathway and the presence of inhibitor activity as a whole. Complement mediates immune reactions. Hypocomplementemia that accompanies some forms of renal disease may indicate immune utilization. Low serum complement levels occur in some patients with severe RA, and may indicate the development of vasculitis. Low levels tend to correlate with active immunologic diseases. Total hemolytic complement, C3, and C4 may be decreased in a variety of diverse clinical situations, in particular in cases in which immune complex activation has occurred. Such problems include cases of SLE, especially if there is nephritis. Hypercomplementemia may be seen as part of the acute phase reaction.