A C4 complement blood test measures the amount of complement component 4 (C4), a protein involved in your immune system’s complement pathway. Doctors may order this blood test when investigating certain autoimmune diseases, immune-system disorders, or unexplained inflammation. However, a C4 result cannot diagnose a condition by itself. Instead, healthcare professionals interpret it alongside your symptoms, medical history, physical examination, and often other laboratory tests. Seeing an abnormal C4 value on a laboratory report can understandably raise questions. Yet both low and high results can have several explanations. Therefore, understanding…
Read MoreC4 Complement Blood Test: Results, High and Low Levels Explained
