Yale New Haven Hospital

Department of Laboratory Medicine
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Streptolysin O antibody

Lab Section: 



Lab Location: 

Main Lab

Test ID: 






Tuesday, Friday


4 days

Specimen Requirements: 

Collection: 5.0 mL Blood in a Gold Top Tube.
Pediatric volume: 0.5 mL.
Unacceptable conditions: Grossly hemolyzed specimens.
Stability: After separation from cells: Ambient: 48 hours; Refrigerated: 7 days; Frozen: 3 months



Clinical Indications: ASO is one of several toxic immunogenic exoenzymes produced by group A beta hemolytic streptococci. An elevated ASO titer usually is an indication of a recent infection with a group A beta hemolytic streptococcus and as such has become relatively routine for the diagnosis and management of acute rheumatic fever and acute glomerulonephritis. Approximately 80-85% of individuals with a current streptococcal infection will demonstrate an elevated ASO titer. It may decrease by the time a patient presents with acute rheumatic fever; therefore a previous streptococcal infection cannot be ruled out due to a negative ASO result. Additonally, it is uncommon for a skin infection to produce a rise in ASO titer. Also, examining for antibodies to DNAase B may be of value.

Reference Interval: 

< 214 IU/mL

CPT Code(s): 


Last Changed: 

12/23/2016 13:28:59

Last Reviewed: 

8/24/2017 12:36:44 PM