What is c4 count test?

The C4 count test measures the level of C4 complement protein in the blood, which is part of the immune system. It helps assess immune function and diagnose conditions related to immune deficiencies or autoimmune diseases, such as systemic lupus erythematosus or rheumatoid Arthritis. Low levels of C4 may indicate complement consumption due to ongoing inflammation or autoimmune activity. The test is usually performed alongside other complement tests for a comprehensive evaluation.