What would happen if a person has a complement deficiency?

Deficiencies in the complement cascade can lead to overwhelming infection and sepsis. In addition to playing an important role in host defense against infection, the complement system is a mediator in both the pathogenesis and prevention of immune complex diseases, such as systemic lupus erythematosus (SLE).

When do you suspect a complement deficiency?

[5] Complement deficiency should also be suspected in a patient with recurrent sinopulmonary infection with normal humoral (antibody) immunity and with/without autoimmunity. Pyogenic infections and sepsis in children and neonates may be an indication of mannan-binding lectin deficiency.

How is complement deficiency diagnosed?

Complement deficiencies are commonly diagnosed with the following tests:

1. Total serum class haemolytic complement (CH-50) test.
2. Alternative haemolytic complement (AP-50) test.
3. Screening for immune complex diseases.
4. Antinuclear serology to test for lupus.
5. Urinalysis.
6. Complete blood count (CBC)

What are the clinical manifestations of complement system deficiency?

The following symptoms (signs) are consistent with complement deficiency in general:

• Recurring infection.
• Auto-immune disorders.
• Glomerulonephritis.
• Joint problems (manifestation)
• Lung function (MBL variant alleles)
• Angioedema.
• Dermatomyositis.
• Vasculitis.

What causes low complement levels?

If your results show lower than normal amounts or decreased activity of complement proteins, it may mean you have one of the following conditions: Lupus. Rheumatoid arthritis. Cirrhosis.

What causes low C3 and C4 complement levels?

This is the result of an acquired disease. If your C3 and C4 levels are reduced, this may be a sign that you have lupus. With lupus, your total complement level may be slightly lower. Low C3 and C4 levels may also be a sign of alcoholic liver disease.

What will happen if a person is deficient of C3 complement system protein?

Prognosis. C3 deficiency can lead to recurrent infections with severe sequelae and high morbidity and mortality. There may be overwhelming sepsis in early life. Deficiencies of the components of the MAC (C5-C9) tend to lead to less severe infections and have a better prognosis with careful management.

What are examples of immune deficiencies?

Types of Primary Immune Deficiency Diseases

• Autoimmune Lymphoproliferative Syndrome (ALPS)
• APS-1 (APECED)
• CARD9 Deficiency and Other Syndromes of Susceptibility to Candidiasis.
• Chronic Granulomatous Disease (CGD)
• Common Variable Immunodeficiency (CVID)
• Congenital Neutropenia Syndromes.
• CTLA4 Deficiency.
• DOCK8 Deficiency.

What are the clinical indications for complement deficiency?

Clinical indications for possible complement deficiencies include recurrent mild or serious bacterial infections, autoimmune disease, or episodes of angioedema (a painless, but often dramatic, swelling under the skin, or swelling in the intestines, which can be extremely painful). Very rarely angioedema in the brain can be fatal.

What is factor B deficiency?

Factor B is an acute phase protein and increases during inflammation. There is only one unconfirmed report of this deficiency in humans. Properdin is the only complement protein that is X-linked. The protein is synthesized by monocytes, granulocytic cells and T-cells.

Are there any known human complement deficiencies?

There is only one unconfirmed report of this deficiency in humans. Properdin is the only complement protein that is X-linked. The protein is synthesized by monocytes, granulocytic cells and T-cells. Several mutant forms of the protein have been identified that result in decreased AP function.

What is complement dysfunction and what causes it?

The diseases that accompany uncontrolled activation or inadequate performance of complement’s functions are often the result of inherited deficiency or subtle impairment of one or more of the components.