Serum supplementation of the C4 component is used in the control of patients with a very low total supplement concentration, in the control of hereditary angioedema, to evaluate disease activity in systemic lupus erythematosus, glomerulonephritis, rheumatoid arthritis anemia.
More information
The complement is a term that describes 20 specific serum proteins belonging to the globulins which in combination with the antigen-antibody complexes induce lysate-sensitized red blood cells with the antibody contained in the complex. The nine essential components of the complement are called C1 to C9.
Component C4 is one of the nine essential components of all complement proteins and participates only in the classical complement activation pathway. Component C4 is found naturally in human colostrum. Deficiency of the C4 component of the complement is an inherited autosomal recessive trait and results in reduced resistance to infections. Activation of complement functions occurs during phagocytic activity, destruction of microorganisms, and inflammatory response. Measuring the levels of C3 and C4 components is useful in distinguishing the cause of glomerulonephritis, because C3 is reduced but C4 is usually normal when the cause is post-streptococcal.
Possible Interpretations of Pathological Values
- Increase: Cancer, chronic urticaria, dermatomyositis, juvenile rheumatoid arthritis, keratoconus, rheumatoid arthritis
- Decrease: Chronic bronchitis, cigarette smoking, congenital C4 deficiency, cryoglobulinemia, glomerulonephritis, purple Henoch-Schoenlein, hepatitis (chronic active), hereditary angioedema, hyperglycemia seronegative, subacute bacterial endocarditis, systemic lupus erythematosus (active), interstitial tubular nephritis and uveitis (TINU syndrome)
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.
