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Complement levels
Total complement activity (CH50, CH100) looks at the overall activity of the complement system. Typically, other tests that are more specific for the suspected disease are performed first. C3 and C4 are the most commonly measured complement components. A complement test may be used to monitor patients with an autoimmune disorder and to see if treatment for their condition is working. For example, patients with active lupus erythematosus may have lower-than-normal levels of the complement proteins C3 and C4.
Dr. Jeff Livingston reviewed this
24 year experience in Obstetrics and Gynecology
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A 35-year old asked:
What would having low complement levels indicate?
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A 31-year old asked:
What do low complement levels indicate is going on?
1 doctor answer • 3 doctors weighed in
A 40-year old asked:
I've never head of complement levels, what do they mean when they are low?
1 doctor answer • 3 doctors weighed in
A 28-year old female asked:
What do you think it means when your complement level comes back high (176) but you test a "low" postive for lupus? This is for my 18 month old son.
1 doctor answer • 1 doctor weighed in
A 45-year old asked:
Should I see a rheumatologist if I have elevated complement levels?
4 doctor answers • 9 doctors weighed in
A 30-year old female asked:
My C4 complement level is low and C3 complement is at the low end of the range (90, ref range 90-180). What could this mean?
2 doctor answers • 4 doctors weighed in
A 39-year old female asked:
Is a consistantly low C4 complement level but normal c1 inhibitor and functional level normal for hae if not in a flare?
2 doctor answers • 4 doctors weighed in
A 21-year old male asked:
Do serum complement levels naturally fluctuate? had one mildly low C4 with normal C3 but when test redone both had risen & C4 was within normal range
1 doctor answer • 1 doctor weighed in
A 32-year old asked:
I have vesico-ureteric reflux and acute hypertension, why would complement levels be an investigation?
1 doctor answer • 1 doctor weighed in
A 21-year old male asked:
Can you have lupus with completely normal bloodwork? ANA, ENA neg, Complement levels normal, CBC normal. ESR of 2 and normal CRP
1 doctor answer • 1 doctor weighed in
A 39-year old female asked:
Can low complement levels cause lichen planus ( armpit) and tinea versicolor?
2 doctor answers • 4 doctors weighed in
A 35-year old male asked:
Have borderline low C3 and C4 complement levels and low 1:80 titre positive ANA speckled. With symptoms relating to sle and sjorgrens - atypical ?
1 doctor answer • 1 doctor weighed in
A 33-year old male asked:
Labcorp says that a serum complement C3 level of 89 mg/dl is low for an adult. Does this sound right?
1 doctor answer • 5 doctors weighed in
A 33-year old male asked:
Can chronic viral infections cause low complement C3 levels? If so, which chronic viruses do this?
1 doctor answer • 2 doctors weighed in
A 49-year old male asked:
What illness could explain ELEVATED C3 and C4 complement serum levels in the presence of angioedema? ANA and Rheum Arth Factor both negative.
1 doctor answer • 1 doctor weighed in
A 43-year old male asked:
Could my severe vitamin d deficiency be the cause of my extremely high complement ch50 level? C3 and C4 are normal.
1 doctor answer • 2 doctors weighed in
A 25-year old female asked:
Rnp antibody, speckled pattern, titer of 1:320. No symptoms or anything. High complement c3 & c4 levels. do I have an autoimmune disease?
1 doctor answer • 1 doctor weighed in
A 31-year old female asked:
What does it mean when you have high levels of complement c4 and sedimentation rate westergren?
1 doctor answer • 1 doctor weighed in
A 33-year old male asked:
I have normal levels of complement C2 and c4. C3 level is low. Ch50 is high-normal(57 u/ml)-(all are serum tests)-what are the possible causes?
1 doctor answer • 1 doctor weighed in
A 44-year old asked:
Diagnosed with high levels of total complement (ch50) and c-reactive protein. What does that mean?
1 doctor answer • 1 doctor weighed in
A 46-year old asked:
What to do if I have high levels of total complement (ch50) and c-reactive protein. what does that mean?
1 doctor answer • 1 doctor weighed in
A 33-year old male asked:
Can you have a normal ch50 (total complement) blood test result, but still have low C3 and/or C4 levels?...Or would low C3 or C4 show up on ch50 test?
2 doctor answers • 4 doctors weighed in
A 51-year old female asked about a female:
My 14yo has C3 level is 71, C4 is 13, C50 is 60. Alkaline phosphatase plasma low 72. Because total complement was ok, we were told she is fine?? Family history of Lupus. She has face rash, cold hands turning purple, low energy. Should I worry?
2 doctor answers • 2 doctors weighed in
A 41-year old asked:
What is complement c3?
1 doctor answer • 4 doctors weighed in
A 33-year old asked:
What does high hemolytic complement mean?
1 doctor answer • 2 doctors weighed in
A 36-year old asked:
What does high immunoglobulin IG m and complement mean?
1 doctor answer • 3 doctors weighed in
A 44-year old asked:
Anyone have lupus or know any information on C4 complement?
3 doctor answers • 5 doctors weighed in
A 28-year old male asked:
I have type 1 obesity. What is the best pill to complement my diet?
2 doctor answers • 4 doctors weighed in
A 33-year old male asked:
Does the human body even use the complement system at all to fight-off viruses?
1 doctor answer • 2 doctors weighed in
A female asked:
Running is my primary form of exercise. What else would complement this for a full body workout for general health? Would yoga be a good option?
2 doctor answers • 3 doctors weighed in
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