Autoimmune connective tissue disease

Autoimmune diseases causes

Autoimmune diseases causes are:

1. Infection by a microorganism, antigenic determinants (epitopes), the most important proteins that resemble antigenic determinants of normal tissues of the host organism. By this mechanism, developed autoimmune glomerulonephritis after streptococcal infection or autoimmune reactive arthritis following gonorrhea.
2. Destruction or necrosis, or changes in their antigenic structure, so that the modified tissue becomes immunogenic for the host organism. By this mechanism, developed autoimmune chronic active hepatitis after suffering hepatitis B.
3. Violating the integrity of the tissue (gistogematicheskie) barriers, separating the norm, some organs and tissues from the blood and therefore immune from the aggression of lymphocytes owner. Moreover, since these antigens in normal tissues in the blood did not fall, the thymus does not produce the destruction of autoaggressive lymphocytes to these tissues. By this mechanism, developing autoimmune thyroiditis.
4. Hyperimmune state (abnormally enhanced immunity) or immunological imbalance in impairment of the "selector" suppressing autoimmunity, thymic function or reduced activity of T-suppressor subpopulation of cells.

The mechanism of development of many autoimmune diseases (systemic sclerosis, nodular periarteriita acquired hemolytic anemia, etc.) has not been elucidated. Most of them are developing the type of delayed-type allergic reactions involving the immune lymphocytes. In autoimmune lesions of blood paramount circulating antibodies in the blood.

As autoantigens can join proteins, nucleic acids, phospholipids, sugars themselves immunoglobulins (rheumatoid factor - is autoantibodies to IgG). In the blood are normal in a small amount of natural autoantibodies, usually IgM-class, do not cause pathological processes, and stimulate tissue regeneration.

Autoimmune diseases can be divided into:

1. Organ-specific (with a lesion of the thyroid gland, adrenal glands, stomach, pancreas - Hashimoto's thyroiditis (Hashimoto's), primary myxoedema, thyrotoxicosis, pernicious anemia, Addison's disease, diabetes mellitus type I, and others).
2. Organonespetsificheskie (with involvement of skin, kidneys, joints, muscles - dermatomyositis, systemic lupus erythematosus, scleroderma, rheumatoid arthritis, etc.).

Detection in serum of various autoantibodies has sometimes decisive diagnostic value for confirmation of a disease, is closely associated with disease activity or may determine the prognosis. Used laboratory medical tests are an important tool in choosing a method of treating and monitoring the effectiveness of therapy.

Prognostic significance change in the level of autoantibodies in an upward titles, and to reduce them. Most autoantibodies are not specific to any disease, they are found in various combinations.

 

Rheumatic diseases

Rheumatic diseases of connective tissue include:

• systemic lupus erythematosus (SLE)
• systemic scleroderma
• Sjogren syndrome
• mixed connective tissue disease
• polymyositis (myositis) or dermatomyositis
• Rheumatoid arthritis (RA)
• myasthenia gravis
• Multiple sclerosis (MS)
• sometimes antiphospholipid syndrome and periarteritis nodosa, although most recent publication is a disease "opens" a group of systemic vasculitis

 

Rheumatic diseases laboratory tests

Rheumatic diseases laboratory tests includes the definition:

• autoantibodies
• immunoglobulins
• circulating immune complexes
• components of the complement system
• acute phase proteins of inflammation
• indicators of dysfunction / injury of endothelial
• Genetic Markers
• markers of bone metabolism

 

Rheumatoid factor (RF)

Rheumatoid factor (RF) - is an antibody against the Fc-fragment of IgG. Most often these antibodies are IgM, but there are IgG-, IgA-, IgE-antibodies. Rheumatoid factor (RF) have 75-80% of patients with rheumatoid arthritis, it can also detect Sjogren's syndrome, scleroderma, dermatomyositis, hyperglobulinaemia, B-cell lymphoproliferative diseases. The presence of rheumatoid factor is considered an important prognostic sign bystroprogressiruyuschego destructive lesions of joints and systemic manifestations of rheumatoid arthritis.

 

Antibodies to cyclic citrullinated peptide (anti-CCP)

Antibodies to cyclic citrullinated peptide (anti-CCP) are a heterogeneous group of autoantibodies that recognize antigenic determinants filagrina and other proteins containing atypical amino acid citrulline. These antibodies are present in 79% of sera from patients with rheumatoid arthritis. Anti-SSR are found in the very early stages of RA. In addition, the test can differentiate between erosive (anti-SSR-positive patients) and neerozivnuyu (anti-SSR-negative patients) forms of RA.

 

Antibodies to a modified citrullinated vimentin (anti-MCV)

Vimentin is a protein of the cytoskeleton of various cell types, such as mesenchymal cells and endothelium, fibroblasts, chondrocytes and osteocytes. It is used as a marker of soft tissue tumors. Vimentin synthesized and modified by macrophages under the regulation of proinflammatory and antiinflammatory cytokines, and occurs in the synovial fluid of RA patients. About half of the RF-negative patients detected by anti-MCV.

 

Circulating immune complexes (CIC)

The formation of circulating immune complexes (CIC) is a physiological mechanism of protection, leading to rapid elimination by reticuloendothelial system or endogenous or exogenous antigens (microorganisms, viruses, parasites, plant antigens, antigens of fungi, pollen, or food).

High levels of circulating immune complexes (CIC) in serum and / or other biological fluids is observed in many inflammatory and malignant diseases that can cause the development of pathology.
Determination of circulating immune complexes (CIC) in serum - an important marker for assessing disease activity, especially in autoimmune diseases.

 

The frequency of finding antibodies (%) in autoimmune diseases

Disease	anti-dsDNA	anti-osDNA	anti-histone	anti-SS-A (Ro)	anti-SS-B (LA)
Systemic lupus erythematosus (SLE)	>90	>90	30-50	10-30	30-50
Drug lupus erythematosus (LCV)	-	30-50	50-90	-	-
Sharp syndrome / mixed connective tissue disease	10-30	10-30	-	-	-
Rheumatoid disease	-	30-50	30-50	10-30	-
Sjogren syndrome	10-30	10-30	-	>90	>90
Scleroderma	10-30	10-30	-	10-30	-
Photosensitive dermatitis, dermatomyositis	10-30	10-30	-	-	-

 

Disease	anti-Sm	anti-RNP/Sm	anti-Scl-70	anti-Jo-1
Systemic lupus erythematosus (SLE)	10-30	10-30	-	-
Drug lupus erythematosus (LCV)	-	-	-	-
Sharp syndrome / mixed connective tissue disease	-	>90	-	-
Rheumatoid disease	-	-	-	-
Sjogren syndrome	-	-	-	-
Scleroderma	-	-	>90	-
Photosensitive dermatitis, dermatomyositis	-	-	-	50-90