ASO Latex Kit

ASO Latex Kit – Diagnostic Test for Streptococcal Infections

The ASO Latex Kit is a rapid agglutination test designed to detect Antistreptolysin O (ASO) antibodies in human serum. These antibodies are produced in response to infections caused by Group A Streptococcus (Streptococcus pyogenes). The ASO test is commonly used to diagnose and monitor post-streptococcal complications such as rheumatic fever, post-streptococcal glomerulonephritis (PSGN), and scarlet fever.

Principle of the Test

The ASO Latex Kit uses the latex agglutination method, where latex particles coated with Streptolysin O antigen react with ASO antibodies in the patient’s serum. If ASO antibodies are present, visible agglutination (clumping) of the latex particles occurs, indicating a positive test result. The degree of agglutination correlates with the ASO concentration in the blood.

Test Procedure

1. Sample Collection – A blood sample is drawn from the patient and the serum is separated.
2. Reaction Setup – A drop of the patient’s serum is mixed with latex reagent on a test slide.
3. Observation – The slide is gently rocked for a few minutes, and any visible clumping indicates a positive reaction.
4. Interpretation –
   • Positive Result: Agglutination occurs, suggesting recent or ongoing streptococcal infection.
   • Negative Result: No visible clumping, indicating no significant ASO antibodies.

Clinical Applications

• Diagnosis of Recent Streptococcal Infections – Confirms exposure to Group A Streptococcus bacteria.
• Monitoring Rheumatic Fever and Glomerulonephritis – Helps assess post-streptococcal immune responses.
• Evaluation of Recurring Infections – Tracks ASO levels over time to detect reinfection or disease progression.