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Antistreptolysin (ASO)

Overview of Group A Streptococcal Infections

Group A streptococci (GAS) are responsible for a range of infections, including skin conditions and angina tonsillaris (strep throat). When these bacteria infect the upper respiratory tract, they can lead to serious complications such as glomerulonephritis, acute endocarditis, Sydenham’s chorea, and acute rheumatic fever. These conditions have the potential to cause long-term damage to vital organs such as the heart and kidneys.

Importance of Early Detection and Treatment

Prompt diagnosis and appropriate antibiotic treatment are essential to prevent the progression of streptococcal infections. In areas like Slough and surrounding towns such as Windsor, Maidenhead, and Langley, timely testing and intervention can significantly reduce the risk of post-infection complications and support long-term health.

Streptococcal Toxins and Immune Response

Group A β-hemolytic streptococci produce several toxic metabolites, including NAD-glycohydrolase, streptodornases (DNases), and hyaluronidase. These substances can trigger immune responses in the body. The immune system often forms antibodies against these bacterial toxins, which helps in assessing the presence and severity of the infection.

Key Antibodies in Streptococcal Testing

The most clinically significant antibody responses include those directed against:

Streptolysin O

Streptococcal DNase

Streptococcal hyaluronidase

Among these, the antistreptolysin O (ASO) antibody test is the most commonly used to evaluate streptococcal infections. Elevated ASO levels are seen in approximately 85% of individuals with acute rheumatic fever, making it a valuable diagnostic tool.

Monitoring ASO Levels for Treatment Efficacy

In Slough and nearby areas, private blood testing for ASO levels can help monitor patient response to treatment. ASO titres should be tested at regular weekly intervals to determine whether the antibiotic therapy is effective or if a persistent antigenic stimulus remains—even after visible symptoms subside.

Private Streptococcal Testing Services in Slough

Residents of Slough and surrounding locations such as Burnham, Farnham Common, and Cippenham can benefit from reliable streptococcal antibody testing. Early detection and regular monitoring using ASO and related tests can aid in managing potential complications and supporting full recovery from Group A streptococcal infections.

There is an additional £20 phlebotomy fee for every donation.