Understanding the quantification of anti-Sm . antibodies

Lupus is a fairly common disease with unpredictable progression. Quantification of anti-Sm antibodies is an important test in the detection and diagnosis of autoimmune diseases such as lupus erythematosus.

Anti-Smith antibodies are a class of autoantibodies that are important to clinical practice. Anti-Sm is directly resistant to 7 nuclear proteins of the cell nucleus, namely B/B', D1, D2, D3, E, F, G.
According to research, anti-Sm is present with frequency 5 to 30% in patients with systemic lupus erythematosus, of which 5% resulted from studies in Europe and 30% from studies in North America. On immunofluorescence, anti-Sm will fluoresce as a speckled pattern. Anti-Sm is an antibody specific for systemic lupus erythematosus but is less commonly used to diagnose lupus than anti-DNA testing. In some cases, anti-Sm can be conjugated with RNP antibodies, but RNP antibodies usually appear more slowly.

The most common types of Anti-Sm are SLE (30%) and MCTD (8%). Anti-Smith antibodies have relatively stable concentrations and little change. Although in previous studies a link between anti-Sm and disease activity levels has been shown. However, recent studies have shown that there is no association between anti-Sm and disease activity levels.
Research by Alba and colleagues has shown an association between anti-Sm and kidney damage, specifically lupus glomerulonephritis. In addition, some authors suggest that one of the predictors of silent kidney injury in SLE patients is anti-Sm.
Besides, anti-Sm is also associated with severe damage such as mental disorders, nerve damage, vasculitis.

3.1 Before conducting the test Quantitative anti-Sm antibody test is actually a type of blood test. Therefore, before the test, the patient does not need to fast or prepare anything special. If there are any specific notes, the doctor will explain them before the test is done.
3.2 The process of performing anti-Sm antibody quantification Anti-Sm antibody quantification is carried out in sequential steps as follows:
The medical professional will wrap a bandage around the patient's arm to stop the blood circulation Disinfect the blood collection site with specialized medical alcohol The sample used is usually venous blood, so the needle will be injected into the vein to collect blood. This step can be done more than once if necessary. Attach the tube to allow enough blood to flow. Remove the bandage around the hand. Clean and disinfect the area where the blood was drawn with cotton wool or gauze. bandage Place a bandage on the area where the blood was drawn 3.3 Notes after the test Your level of pain may depend on many different factors such as: Pain sensitivity, vein condition or technique medical professional blood draw. However, most blood tests for anti-Sm antibodies will not cause you much pain, often just like a needle or an ant sting.
After completing the sampling process, you need to pay attention to gently press your hand on the dressing to help control blood at the needle puncture area. In addition, you do not need to pay attention to anything else, you can return to normal activities immediately after.

3.4 Instructions for reading anti-Sm antibody quantification results Anti-Sm antibody quantification results can be given in two forms:
Negative result: Means the patient is completely normal
Positive result: Depends an abnormal increase in each type of antibody that can lead to different disease conclusions. Specifically:
Increased amount of anti-Sm antibodies: diagnosis of systemic lupus erythematosus. Increased levels of anti-RNP antibodies: Systemic lupus erythematosus, discoid lupus erythematosus, or mixed connective tissue disease. Increased anti-Jo-1 antibodies: Autoimmune myositis or pulmonary fibrosis. There will be some variation within the normal range of the anti-Smith antibody quantification technique between testing facilities. To better understand their quantitative results, patients can consult a specialist doctor.
Understanding the quantification of anti-Sm antibodies in particular and antinuclear antibodies in general has important implications in the diagnosis and treatment of autoimmune diseases.
Customers who have a need to find out the quantification of anti-Sm antibodies need to find reputable and quality facilities so that they can receive timely advice as well as proper treatment. Vinmec International General Hospital is proud to be one of the facilities providing professional and comprehensive medical examination and treatment services.

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