What is the clinical significance of the ASO test?
Clinical Significance of ASO Test. The antibodies level starts to rise in 1-3 weeks after streptococcal infection, peaks in 3-5 weeks, and then goes back to insignificant level over 6-12 months, so a positive test can indicate current but more recent group A, C, and G streptococcal infection.
What is the ASO titer test?
The antistreptolysin O (ASO) titer test is a blood test that checks for a strep infection. When you come into contact with harmful bacteria, your body produces antibodies to defend itself against these bacteria. Your body produces antibodies specific to the bacteria they fight. The ASO titer test...
What is Aso test for strep throat?
Antistreptolysin O Titer (ASO) Test. Medically reviewed by Judith Marcin, MD on January 6, 2017 — Written by Darla Burke. The antistreptolysin O (ASO) titer test is a blood test that checks for a strep infection. When you come into contact with harmful bacteria, your body produces antibodies to defend itself against these bacteria.
What is Aso antistreptolysin O (ASO)?
Antistreptolysin O (ASO) is an antibody. This test is done to see if you have the ASO antibody in your blood. An antibody is a protein that is made by your immune system. The ASO antibody shows if you have had an infection caused by the Streptococcus bacteria. Some illnesses are caused by a previous Streptococcus bacterial infection.
What is the ASO test used for?
The ASO test or antistreptolysin O titer test is used to measure the antibodies produced by your body as a response to the group A Streptococcus (G...
Understanding the test results of the ASO test
The normal range of the ASO test is less than 200 for adults, and it is less than 100 for children below five years. If your ASO test results are h...
Why do I need an ASO test?
Your doctor will advise an ASO test if you exhibit symptoms of post-streptococcal complications. The symptoms of post-streptococcal complications a...
What happens during an ASO test?
Your doctor might advise you to refrain from eating or drinking anything for six hours before the test. During the test, you will have to give a bl...
What is the normal range of ASO?
The normal range of the ASO test for adults is less than 200. The normal range of the ASO test for children below five years is less than 100. If y...
What is the ASO blood test used for?
The ASO blood test is used to measure the level of antistreptolysin antibodies in your blood. If your blood test shows results above 200, it means...
Is fasting required for an ASO blood test?
The ASO test is conducted to measure the level of antistreptolysin antibodies present in your blood to check whether you had a streptococcus infect...
What are the symptoms of ASO positivity?
Some symptoms that ASO positive patients display are: Joint swelling and pain Fever Skin rash Heart inflammation (carditis), leading to shortness o...
How do I prepare for an ASO test?
Your doctor might tell you not to eat or drink anything for six hours before the ASO test. Your doctor might also advise you to stop taking some me...
What are the complications associated with an ASO test?
Although the ASO test is generally safe, it might include certain complications: Difficulty in obtaining blood, requiring multiple needle pricks. B...
What is ASO test?
ASO test is done by serological methods like latex agglutination or slide agglutination. ELISA may be performed to detect the exact titre value. The test principle, procedure and interpretation presented here are based on Latex Anti-Streptolysin O (ASO) test.
What is ASO agglutination?
ASO latex agglutination is the rapid and simple test for the qualitative and semi-quantitative measurement of antibodies to Antistreptolysin-O in human serum. This method is based on an immunological reaction between streptococcal exoenzymes bound to biologically inert latex particles and streptococcal antibodies in the test sample. The reagent has been adjusted in the way that presence of an ASO titer of 200 IU/mL or higher in the serum gives a visible agglutination of the latex particles.
What is Anti-Streptolysin O (ASO)?
Anti-Streptolysin O ( ASO or ASLO) is the antibody made against streptolysin O, an immunogenic, oxygen-labile hemolytic toxin produced by most strains of group A and many strains of groups C and G streptococci.
What is the effect of SLO on the heart?
The SLO toxin has direct toxic effects on heart tissue. In the course of a streptococcal infection, SLO stimulates the production of specific antistreptolysin (ASO) antibodies, which in-vitro, neutralize the hemolytic properties of the antigen.
What is the letter O in Streptococcus pyogenes?
The letter “O” indicates that this toxin is oxygen labile. The SLO toxin has direct toxic effects on heart tissue. In the course of a streptococcal infection, SLO stimulates the production ...
Does ASO test detect streptolysin?
Since streptolysin is only one of several Streptococcus A exoenzymes, the ASO test will not detect the other antibodies to exoenzymes of Streptococcus A.
Why is an ASO test performed?
ASO titre test is done specifically to determine a Streptococcus infection by assessing the levels of antibodies produced in response to streptolysin O.
How do you prepare for an ASO test?
Your doctor will provide instructions related to any preparations before the test. You will likely be asked to fast for 6 hours before the test.
How is ASO test performed?
A lab technician will place an elastic band around your upper arm to stop the flow of blood, which enables easy identification of a vein for withdrawal of blood sample
What do ASO test results indicate?
Normal results: A negative test result indicates the absence of a Streptococcus infection. However, the test may be performed again after two weeks. Normal values may vary slightly among laboratories. The results must be discussed with a doctor to get a clear diagnosis.
Why do you need an ASO titer?
You may need an ASO titer blood test if your health care provider suspects you have one of the following complications. Infections . Without proper treatment, strep bacteria can spread to other areas of your body. This can cause infections in your tonsils, sinuses, skin, middle ear, and blood. Scarlet fever.
What does it mean when your ASO is low?
A negative ASO level or a very low ASO level means that you probably haven't had a strep infection recently. Your body starts producing ASO antibodies between a week and a month after you're infected. Three to five weeks after you develop the illness, you will have the most antibodies in your blood.
How long does it take for ASO to increase?
An antistreptolysin O titer measures how much ASO is in your blood. The ASO antibodies start increasing about a week after you experience a strep infection. They keep increasing for several weeks and then start to decrease.
What is an antistreptolysin o titer?
An antistreptolysin O titer (ASO) is a blood test used to determine if you've had a recent infection caused by group A streptococcus bacteria. It's not used to diagnose a current strep infection, such as strep throat. Instead, this test is mainly used if you have symptoms that your doctor thinks may have ...
How long before ASO test can you eat?
This test uses a blood sample drawn from a vein, usually in your hand or arm. Your doctor may tell you not to eat for six hours before the test. Your doctor may do another ASO titer test two weeks later to see if your levels are increasing or decreasing.
Can a strep throat test be used for strep throat?
It's not used to diagnose a current strep infection, such as strep throat. Instead, this test is mainly used if you have symptoms that your doctor thinks may have been caused by a previous strep infection that went untreated.
What is ASO test?
Antistreptolysin O (ASO) is an antibody targeted against streptolysin O, a toxic enzyme produced by group A Streptococcus bacterium. ASO and anti -DNase Bare the most common of several antibodies that are produced by the body’s immune system in response to a strep infection with group A Streptococcus. This ASO test measures the amount of ASO in the blood.
What does rise in ASO mean?
8. Rise in ASO indicates concurrent, past or present infection.
What is the anti-streptolysin O test?
The anti-streptolysin O test is based on the fact that patients with Streptococcus pyogenes (group A streptococcal) infections develop antibodies that inhibit the hemolytic activity of streptolysin O.
What is the function of streptolysin O?
4. The “O” in the name stands for oxygen-labile; the other related toxin being oxygen-stable streptolysin-S. The main function of streptolysin O is to cause hemolysis
What do I need to know about ASO results?
What do I need to know about the test results. Your healthcare provider will explain what your test results mean. The presence of ASO does not tell which disease you have now. It only tells if you have had a streptococcus infection that may have caused your illness. Several ASO tests may need to be done over a period of weeks.
How do I get ready for the test?
Your healthcare provider will tell you when to have your blood test done. The blood test may be done before or after eating. Ask your healthcare provider if you should wait to take your medicines until after your blood is taken. Wear a short-sleeved or loose shirt on the day of the test. This will make it easier to draw your blood.
How to help plan for lab work?
You have the right to help plan your care. To help with this plan, you must learn about your lab tests. You can then discuss the results with your healthcare providers. Work with them to decide what care may be used to treat you. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.
What does ASO stand for in medical terms?
Previous Elevated ASOT meaning. Basically: ASO is a medical term for “antistreptolysin O ”, antistreptolysin O is a medical term for “ASO antibody” or “ASO Ab”, which is a weapon released against foreign attacks by a substance called “streptolysin O”, streptolysin O is a bacterial toxin breaks blood cells and causes hydrolysis of your blood, ...
How long does it take for ASO to return to baseline?
How long time does ASO titer take to be normal again? ASO titres return to baseline levels in 23 months.
What is the normal ASO titer?
Titer or titre means “concentration” or “unit”. Normal ASO titer range is 100 IU/mL for adult and preschool age child , u0001200 IU/mL for child at school age. It’s better to call it negative level than normal level. ASO test is a measure of the antistreptolysin O antibodies level in your blood,
What Is Anti-Streptolysin O (ASO)?
Clinical Significance of Aso Test
- An antistreptolysin titer greater than 166 Todd units (or >200 IU) is considered a positive test in adults, while The normal value for adults is less than 166 Todd units, which indicates a negative test. Measurement of ASO antibody titre is important in the investigation of post-streptococcal diseases, particularly acute poststreptococcal glomerulonephritis and rheumatic fever. 1. Over 8…
Tests For Aso
- ASO test is done by serological methods like latex agglutination or slide agglutination. ELISAmay be performed to detect the exact titre value. The test principle, procedure and interpretation presented here are based on Latex Anti-Streptolysin O (ASO) test.
Principle of The Test
- ASO latex agglutination is the rapid and simple test for the qualitative and semi-quantitative measurement of antibodies to Antistreptolysin-O in human serum. This method is based on an immunological reaction between streptococcal exoenzymes bound to biologically inert latex particles and streptococcal antibodies in the test sample. The reagent has...
Qualitative Test
- Procedure:
1. Bring all reagents and specimens to room temperature. 2. Place one drop (50 µl) of the positive control and 50 µl of the patient serum into separate circles on the glass slide. 3. Shake the ASO latex reagent gently and add one drop (45 µl) on each circle next to the sample to be tested and … - Results and Interpretation:
1. Negative result: No agglutination of the latex particles suspension within two minutes. 2. Positive result: An agglutination of the latex particles suspension will occur within two minutes, indicating an ASO level of more than 200 IU/ml.
Semi-Quantitative Test
- Procedure:
1. Serum to be titrated is serially diluted (1:2, 1:4, 1:8 etc) in 0.9 g/L saline solution. 2. Place one drop of positive control on slide. Do not attempt to dilute the ASO positive control serum for comparative or other purposes as no correlation exists between actual titre of the control and tit… - Results and Interpretation:
The serum ASO titre can be defined as the highest dilution showing a positive result. The approximate ASO level (IU/ml) present in the sample can be optained by the following formula: 1. ASO Titre (IU/ml) = Highest dilution with positive reaction x Reagent sensitivity ( 200 IU/ml) e.g. i…
Limitations of The Test
- Highly haemolyzed and lipemic serum as well as plasma interfere with the test.
- Non-streptococcal conditions that occasionally cause positive reactions (usually less than 500 IU/ml) in ASO antibody tests include rheumatoid arthritis, tuberculosis, pneumococcal pneumonia, gonor...
- Since streptolysin is only one of several Streptococcus A exoenzymes, the ASO test will not d…
- Highly haemolyzed and lipemic serum as well as plasma interfere with the test.
- Non-streptococcal conditions that occasionally cause positive reactions (usually less than 500 IU/ml) in ASO antibody tests include rheumatoid arthritis, tuberculosis, pneumococcal pneumonia, gonor...
- Since streptolysin is only one of several Streptococcus A exoenzymes, the ASO test will not detect the other antibodies to exoenzymes of Streptococcus A.
