Systemic vasculitis is a group of autoimmune disorders characterized by inflammation of blood vessels throughout the body. It is caused by the immune system attacking blood vessel walls, often producing anti-C1q antibodies that lead to decreased complement C1q levels and vascular damage. The Complement Component C1q test is the most important test for diagnosis because it directly measures this critical immune protein reduced in active vasculitis.
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Systemic vasculitis is caused by an autoimmune response where the immune system mistakenly attacks blood vessel walls throughout the body. The body produces autoantibodies, particularly anti-C1q antibodies, that target complement proteins essential for normal immune function. This autoimmune attack triggers inflammation that damages blood vessels of various sizes, leading to restricted blood flow and potential organ damage. The exact trigger for this immune system malfunction is not always clear, but it can be associated with infections, certain medications, or other underlying autoimmune conditions.
The Complement Component C1q test is the most important test for systemic vasculitis because it directly measures levels of the C1q protein that becomes depleted when the body produces anti-C1q antibodies. These antibodies are closely associated with active vascular inflammation and tissue damage in vasculitis. Low C1q levels combined with clinical symptoms strongly indicate active disease. This test is valuable not only for initial diagnosis but also for monitoring disease activity during treatment. Additional tests like inflammatory markers (ESR and CRP), complete blood count, and organ-specific tests may be ordered alongside C1q testing to provide a comprehensive assessment of disease severity and organ involvement.
You should get tested if you experience unexplained fever, fatigue, and weight loss along with signs of organ involvement such as skin rashes or lesions, numbness or weakness in limbs, joint pain, or breathing difficulties. Testing is especially important if you notice purple spots on skin (purpura), persistent sinus problems, blood in urine, or sudden vision changes. If you have another autoimmune condition and develop new symptoms affecting multiple body systems, prompt testing can help detect vasculitis early. Early diagnosis through blood testing leads to timely treatment that can prevent serious organ damage and improve long-term outcomes.
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What this means
Your testosterone levels are slightly below the optimal range. While this is not necessarily cause for concern, it may contribute to occasional fatigue, reduced motivation, or lower muscle mass over time.
Recommended actions
Increase resistance or strength training
Prioritize 7–8 hours of quality sleep per night, try to reduce stress
Include more zinc- and magnesium-rich foods (like shellfish, beef, pumpkin seeds, spinach)
Consider retesting in 3–6 months
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