Group A streptococci (Streptococcus pyogenes) produces streptolysin which is a cytolysin. Infected patients mount an immune response to streptolysin O which can be detected 1 week and peaks 2 to 4 weeks after the infection. In patients without complications or reinfections the anti-streptolysin O (ASO) titre falls to pre-infection levels within 6 to 12 months. Elevated ASO titres are seen in 80-85% of patients with rheumatic fever and 95% of patients with post-streptococcal glomerulonephritis. Indicated in Any condition associated with infection by streptococcus pyogenes e.g. rheumatic fever, nephritis, arthritis etc.
Tube
Serum Gel
ID
12752
Availability
Weekdays
Additional Information
Measurement can be useful diagnostically if recent infection with streptococci is known to be important in aetiology. Diseases include rheumatic fever, post streptococcal glomerulonephritis and scarlet fever. A rise in ASO titre above 408 U/mL is associated with recent strep infection. Elevated ASO titres are seen in 80-85% of patients with rheumatic fever and 95% of patients with post-streptococcal glomerulonephritis.
Turn Around
7 days
Send to
Leeds General Infirmary
Clinical Immunology
Old Medical School
Great George Street
Leeds
LS1 3EX
Collection Con
No restrictions
Frequency
Daily
Sample REQ
Blood
Ref. Range (Male)
<408
Ref. Range (Female)
<408
Ref. Range Notes
<408 IU/mL
Units
IU/mL
IP Acute TAT
Contact Laboratory
IP Routine TAT
7 days
GP Acute TAT
Contact Laboratory
GP Routine TAT
7 days