C4 – Complement 4

🔍 Overview

The Complement 4 (C4) test measures the level of C4 protein in the blood, which is part of the complement system—an important component of the immune system. It helps evaluate immune function and detect autoimmune or inflammatory disorders.

📋 Test Summary

This test helps to:

• Assess immune system activity

• Diagnose and monitor autoimmune diseases (e.g., lupus)

• Evaluate inflammatory conditions

• Support investigation of recurrent infections

• Monitor response to treatment in immune disorders

✔ Commonly ordered with C3 complement test
✔ Useful in rheumatology and immunology evaluations

⏱ Reports Within: 24 Hours
🧪 Sample: Blood
👶👩👨 Age: All Age Groups
🚻 Gender: Male and Female
🍽 Fasting: Not Required