Complement C4
C4
Description
"Complement C4" test evaluates the amount of complement C4 protein, which helps regulate immune responses and inflammation. Doctors often order this test when investigating autoimmune conditions like lupus, Sjögren’s syndrome, or hereditary angioedema. Low C4 levels may indicate complement system dysfunction, while high levels could point to infection or systemic inflammation. Results provide important insights into immune activity and help tailor treatment. Ongoing monitoring lets doctors track progress and adjust care based on changing symptom patterns.
Test Category
Proteins
Procedure
Invasive
Sample Type
Blood – Serum
Units
Milligrams per Deciliter | Grams per Liter
Procedure Category
Blood Draw
Test Group
Immune System Group
Test Group Description
Immune System Group: By evaluating various aspects of immune system function and health, this group offers insights into immune responses and related health considerations.
Optimal Range
For All Individuals:
Conventional Unit: 16.00–34.00 mg/dL
SI Unit: 0.16–0.34 g/L
Normal Range
For All Individuals:
Conventional Unit: 12–38 mg/dL
SI Unit: 0.12–0.38 g/L
Results That Differ From The Norm (Direct and Indirect Causes)
Increased levels may indicate:
Cancer
Ulcerative colitis (inflammatory bowel disease)
Decreased levels may indicate:
Bacterial infections
Cirrhosis (advanced liver scarring)
Glomerulonephritis (inflammation of the kidney's filtering units)
Hepatitis (inflammation of the liver)
Hereditary angioedema (genetic disorder causing swelling)
Kidney transplant rejection
Lupus nephritis (kidney inflammation due to lupus)
Malnutrition
Rare inherited complement deficiencies
Systemic lupus erythematosus (autoimmune disease)
Key Reasons For Testing
Detecting Inflammation: Identifies inflammation caused by conditions like lupus or rheumatoid arthritis.
Immune System Function: Assesses how well your immune system defends against infections and maintains balance.
Autoimmune Disease Diagnosis: Helps diagnose conditions like lupus nephritis or autoimmune hepatitis.
Kidney Health: Evaluates kidney function in diseases like glomerulonephritis.
Cardiovascular Risk: Links elevated levels to a higher risk of heart disease.
Metabolic Syndrome: Spots early signs of diabetes or related concerns like high blood pressure.
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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