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Anti Streptolysin O Titer

Also known as ASO titer, ASLO titer

₹540~~₹600~~ 10% Off

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation is required.

Understanding Anti Streptolysin O Titer

What is Anti Streptolysin O Titer?

The Anti Streptolysin O Titer is a blood test that measures the levels of antibodies against streptolysin O, a toxin produced by group A streptococcus bacteria. It helps diagnose recent streptococcal infections and related complications, such as rheumatic fever and acute glomerulonephritis.

The Anti Streptolysin O Titer test looks for antibodies in your blood that your body makes while fighting off Group A Streptococcus (GAS) bacteria. This bacteria can cause various infections including strep throat, scarlet fever, skin infections, cellulitis etc.

The Anti Streptolysin O Titer test helps identify a recent or past streptococcal infection. It is particularly useful in diagnosing complications that arise from streptococcal infections, such as rheumatic fever (a serious complication of untreated strep throat, affecting the heart, joints, brain and skin) and post-streptococcal glomerulonephritis (an inflammation of kidneys, following a streptococcal infection, leading to kidney damage), which can occur weeks after the initial infection.

This test is recommended for individuals showing symptoms of a recent streptococcal infection or related complications, including joint pain, skin rashes, fever, or kidney problems. The ASO levels can help tell whether a streptococcal infection might be responsible for these symptoms.

Elevated ASO titres can suggest that the body has mounted an immune response to a recent strep infection. However, ASO levels can sometimes be temporarily elevated in individuals due to other factors like long-term illnesses, other infections etc., or even in healthy individuals without any symptoms.

No special preparation is required for this test. However, inform your doctor about any medications, supplements or any underlying medical conditions you may have, as these factors could potentially affect the test results.

Lab test results may vary across laboratories. Abnormal test results require an expert interpretation; therefore, never try to self-medicate at home based solely on these results, and always consult a doctor for a proper understanding of the test results as the insights from this test helps doctors assess the severity of the infection and determine appropriate treatment plans.

What is Anti Streptolysin O Titer used for?

The Anti Streptolysin O Titer test is done:

To confirm exposure to Streptococcus pyogenes bacteria.
To help diagnose rheumatic fever as indicated by elevated ASO levels.
To monitor the effectiveness of antibiotic treatment over time against streptococcal bacterial infections.
To investigate potential complications of streptococcal infections such as acute glomerulonephritis.
For risk assessment of autoimmune disorders associated with streptococcus bacterial infection like rheumatic fever or post-streptococcal glomerulonephritis.

What does Anti Streptolysin O Titer measure?

The Anti Streptolysin O Titer test measures the level of antibodies in the blood that target streptolysin O, a homogeneous exotoxin produced by the Streptococcus pyogenes bacteria. When the body is infected with this bacteria, it produces antibodies, including ASO, as part of the immune response to neutralize the toxin. The ASO titres quantifies the concentration of ASO antibodies in the bloodstream, signaling the body’s immune response to a recent or ongoing streptococcal infection.

An abnormal or positive test result means you recently had a streptococcal infection, even if you had no symptoms. Additionally, monitoring ASO levels over time can help assess the efficacy of the treatment and detect any potential complication, such as rheumatic fever or acute glomerulonephritis which may arise as a result of streptococcal infection. Therefore, the Anti Streptolysin O Titer test plays an important role in diagnosing and managing streptococcal infections and associated conditions.

Interpreting Anti Streptolysin O Titer results

Interpretations

Normal ASO level:

Children (up to 12 years of age): Below 150 IU/ml

Adults (above 12 years of age): Below 200 IU/ml

Higher than normal ASO levels indicate an infection of Streptococcus bacteria.

Low ASO titer indicates no recent infection. This is confirmed if the low levels persist in the subsequent test performed after 10 to 15 days. Other tests like Anti-Dnase B Test can also be performed.

Higher than normal ASO titer levels and continuously rising ASO titer in subsequent tests indicates a recent and ongoing infection.

High ASO levels which decline subsequently indicate a Streptococcus infection which is resolving or being cured.

A positive result in the ASO test (Higher than normal ASO levels) confirms a past Streptococcal infection. A positive result can thus help in the diagnosis of conditions like Poststreptococcal Glomerulonephritis (PSGN), Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus (PANDAS), and rheumatic fever.

Note: ASO Test results may be negative (within normal range) in upto 20% of the patients suffering from Acute Rheumatic Fever (ARF). Other tests may be performed to confirm the condition in these cases.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Anti Streptolysin O Titer

Frequently Asked Questions about Anti Streptolysin O Titer

Q. What is the Anti Streptolysin O Titer test used for?

The Anti Streptolysin O Titer test is a blood test used to determine if you've had a recent infection caused by group A streptococcus bacteria.

Q. Why do I need the Anti Streptolysin O Titer test?

Your doctor may recommend the Anti Streptolysin O Titer test if you have symptoms of a recent streptococcal infection or its associated complications, such as rheumatic fever, or streptococcal glomerulonephritis. This test helps in diagnosing these conditions and determining if recent streptococcal infection is the cause of your symptoms.

Q. What are the risks associated with the Anti Streptolysin O Titer test?

The risks associated with this test are generally minimal. However, some people may experience mild pain or discomfort at the site from where the blood sample is taken, which is usually self-limiting.

Q. What do the abnormal test results mean?

Elevated levels of ASO antibodies indicate a recent or past infection with Streptococcus group A bacteria (streptococcus pyogenes). High titres suggest that the body has produced antibodies in response to streptococcal infection. Low or normal levels suggest that there has been no recent streptococcal infection or that the immune response was minimal.

Q. Can high ASO titres cause joint pain?

Increased ASO Titre levels in the blood may harm the heart and joints.

Q. What is the treatment for Antistreptolysin?

Your body makes the antistreptolysin O antibodies when you have a streptococcal (strep) infection. Usually, when you have a strep infection like strep throat, you receive antibiotics that kill the strep bacteria.