A.S.O. Titre

Function

The Antistreptolysin O (ASO) titre measures the amount of antibodies the body produces against streptolysin O, a toxin released by Group A Streptococcus bacteria. It does not detect the bacteria itself but rather confirms that a person has had a recent or past infection with 'Strep'.

Why it is Ordered

This test is vital for diagnosing complications that arise after a strep throat or skin infection has cleared. These are known as post-streptococcal sequelae. If a patient (often a child) develops joint pain, heart palpitations, or kidney swelling weeks after a sore throat, the ASO titre helps prove the link to a previous Strep infection.

Associated Conditions

• Rheumatic Fever: An inflammatory disease that can affect the heart, joints, brain, and skin.
• Post-Streptococcal Glomerulonephritis: A kidney disease that follows a strep infection.
• Bacterial Endocarditis: Infection of the heart valves.
• Scarlet Fever: If symptoms persist or complications are suspected.