Rheumatoid arthritis is a multifactorial, autoimmune disease with progressive joint damage; However, injuries to the skin, blood vessels, lungs and other organ systems are also revealed.
Table of Contents
The autoimmune nature of the disease causes immune inflammatory reactions in tissues and as a result chronic inflammatory and degenerative processes.
Three main groups of diseases are distinguished
Seropositive, seronegative and juvenile rheumatoid arthritis
seropositive During rheumatoid arthritis, a specific protein called rheumatoid factor, or autoantibodies developed against one's own connective tissue (anti-CCP) is found in the blood serum. Almost 80% of rheumatoid arthritis cases are seropositive.
seronegative Rheumatoid factor or autoantibodies are not detected in blood serum during rheumatoid arthritis, although the course of the disease is often no less aggressive. Diagnosis is based on additional laboratory studies, radiological and clinical data.
Juvenile (idiopathic) rheumatoid arthritis is the most common form of childhood arthritis. Symptoms may be temporary or last a lifetime. The disease is severe and affects the quality of physical development.
The first symptoms of rheumatoid arthritis are manifested by damage to small-caliber joints - ankle and metatarsal-phalangeal and inter-phalangeal joints. Joints are swollen, red, movement is limited. Symptoms may decrease periodically (remission phase) and then develop again (relapse phase).
As the disease progresses, lesions spread to larger joints: wrist, elbow, ankle, knee, and sometimes shoulder and hip joints. The disease has a relapsing-remitting, progressive character and eventually leads to irreversible deformation and disability of the affected joints.
In addition to the joints, almost half of the patients suffer from:
Rheumatoid arthritis is diagnosed based on clinical, instrumental and laboratory data.
Laboratory tests are informative:
- General blood test - provides information about the ignition process. In addition, the assessment of the ratio of different blood cells gives us a complete picture of the general condition.
- Erythrocyte sedimentation rate (eds) – provides information about the existence of an inflammatory process. During an acute inflammatory process, erythrocytes stick to each other, the formed conglomerates are easily precipitated. EDS may also be elevated during a chronic inflammatory process. An isolated determination of EDS does not provide accurate information about rheumatoid arthritis. Informative in combination with other tests.
- C reactive protein Determination (CRP) – this protein is produced in the liver and helps the immune system fight the infectious agent during the infectious process. The result of this is the development of inflammation. An autoimmune process can also cause an increase in the titer of C-reactive protein in the blood. Similar to EDS, determination of C-reactive protein in isolation is ineffective in the diagnostics of rheumatoid arthritis, although a full panel of laboratory studies provides data on the course of the inflammatory process and immune status.
- Determination of rheumatoid factor (RF) - Rheumatoid factors are immune proteins that sometimes show autoaggression against their own tissue. The quantitative determination of these proteins gives us an idea of the severity of the autoimmune process. A high RF titer often indicates the presence of rheumatoid arthritis or Sjogren's disease, as well as other autoimmune processes.
- ANA panel - Antinuclear antibodies are immunoglobulins developed against cell nuclear proteins, which are an important diagnostic marker of autoimmune diseases, including rheumatoid arthritis. In ANA-positive cases, a detailed study of ANA subclasses is performed on the patient
- ENA Panel –SS-A, SS-B, RNP, SM, SCL-70, JO-1.
- Other studies: physical examination. Instrumental studies: radiography, magnetic resonance imaging and others.
Detection / determination of ANA in the blood is the best screening test for the diagnostics of systemic connective tissue diseases. The prevalence of ANA in such patients is 20 to 100%.
To identify rheumatic diseases, it is important to distinguish between different antibodies in the ANA group. Two main categories of antinuclear antibodies are currently described:
- Autoantibodies whose targets are DNA and histones.
- Autoantibodies whose target is soluble nuclear antigens.
Target antigens of antinuclear antibodies are highly diverse. Therefore, if there is a positive result in the study of general antinuclear antibodies, it is necessary to test for specific antibodies that will help us diagnose a specific autoimmune disease.
anti-nuclear antibodies types:
- Anti-Ro52 Antibodies - It is non-specific and is found in both rheumatic and non-rheumatic diseases. It is often characteristic of Sjogren's syndrome.
- Anti-PM-Scl Antibodies Target: A protein complex involved in ribosome synthesis. Characteristic of the complex form of systemic scleroderma with poliomyositis / dermatomyositis.
- Anti-CENP In Antibodies Target: A protein involved in cell division. CENP B is a serological marker for CREST syndrome (a subtype of progressive systemic scleroderma).
- PCNA Antibodies Target: A protein involved in DNA replication and repair and cell cycle regulation. It is found in 3% of patients with systemic lupus erythematosus.
- double stranded DNA-He against Antibodies - is a diagnostic marker of systemic lupus erythematosus, is characterized by high specificity (found in 30-90% of patients with lupus erythematosus). It is also used to monitor the clinical activity of the disease. A small percentage can be found in the case of drug-induced lupus erythematosus, rheumatoid arthritis and scleroderma.
- Antinucleosomal Antibodies - They can be detected in systemic lupus erythematosus, prior to double-stranded DNA antibodies.
- antihistone Antibodies - Target: Histons. Is found in 95% of drug-induced systemic lupus erythematosus.
- ribosomal P-of protein against Antibodies - is a marker of neurolupus (damage to the central and peripheral nervous system caused by lupus erythematosus).
- Antimitochondrial AMA M2 Antibodies Target: Enzyme pyruvate dehydrogenase. Its elevated titer confirms the diagnostics of primary biliary cirrhosis. Has a prognostic value in patients with signs of biliary stasis and indicates the risk of developing biliary cirrhosis.
- Anti-DFS70-Antibodies - Associated with atopic dermatitis and prostate cancer. Its highest prevalence is confirmed in patients with Vogt-Harada syndrome (66.7%), autoimmune thyroiditis (55%) and atopic dermatitis (30%).
A diagnostic tool for rheumatoid diseases is the ENA panel, which examines autoantibodies against nuclear extractable proteins:
Anti-SS-A – The most commonly detected ENA antibody. It is associated with systemic lupus erythematosus, its subacute subcutaneous course, neonatal lupus, etc.
Anti-SS-B - It is a typical marker of autoimmune connective tissue diseases. It occurs in Sjogren's disease, scleroderma, myositis, systemic lupus erythematosus.
Anti-RNP - Autoantibodies against ribonucleoproteins. It occurs in 45% of patients with systemic lupus erythematosus, however, it is also characteristic of other connective tissue diseases: Sjogren's syndrome, scleroderma and polymyositis.
Anti-SM - Smith's autoantibodies are formed against small nuclear ribonucleoprotein - Smith, which consists of B, B1, D, E, G protein subunits. Smith's autoantibodies are typical of systemic lupus erythematosus and are present in 30% of patients.
Anti-SCL-70 - Autoantibodies are present in 20% of patients with systemic scleroderma and often indicate a poor clinical prognosis.
Anti-JO-1 - It is an autoantibody characteristic of myositis, which occurs in patients with idiopathic inflammatory myopathies. These antibodies are directed against histidyl transport RNA synthetase and inhibit histidyl attachment to transport RNA during protein synthesis. A form of polymyositis and dermatomyositis with lung damage is often associated with it. The anti-JO-1 antibody titer correlates directly with disease activity.
When Let's hold on test antinuclear on antibodies?
- When autoimmune systemic disease of connective tissue (collagenosis) is suspected
- To diagnose and evaluate the activity of such diseases as systemic lupus erythematosus, progressive systemic sclerosis, Sjogren's syndrome, polymyositis/dermatomyositis.
How Get ready For the test?
Food, water and other products are not affected by the test results.
Of results possible Interpretation
Positive Result Confirms the presence of specific antibodies.
weak signal Indicates that the presence of autoantibodies is unclear and questionable. Depending on the patient's symptoms, the test may be repeated every 1-2 months.
Negative Result Indicates the absence of specific autoantibodies.
Laboratory "Synevo" Offers Rheumatoid arthritis diagnostic tests and panels:
|Name of the test||Category||Price||CODE||Response time (working day) **||Location of the analysis ****||Buy||hf: categories|