ASO – Antistreptolysin

Alternate Name: Aso

  | ASLO

SAL Code:

802

CPT:

86060

Loinc:

5370-2

Turn Around Time:

1 Day

Setup:

Daily

Units:

IU/mL

Department:

Special Chemistry

Specimen Requirements:

Primary Tube:

SST

Primary Substance:

Serum

Temperature

Period

Stable Fridge:

10 Days

Rejection Criteria:

Gross hemolysis; lipemia; improper labeling

Clinical Info:

Streptolysin O is a hemolysin produced by group A streptococci. In an infected individual, Streptolysin O acts as a protein antigen to which the patient mounts an antibody response. A rise in titer begins about 1 week after infection and peaks 2-4 weeks later. In the absence of complications or re-infection, the ASO titer will usually fall to pre-infection levels within 6-12 months. Both clinical and laboratory findings should be correlated in reaching a diagnosis.
Over 80% of patients with acute rheumatic fever and 95% of patients with acute glomerulonephritis due to streptococci have elevated levels of ASO.

Additional Information:

The ASO test is primarily used to help determine a recent strep infection with group A Streptococcus.

Sample Collection:

Collect patient samples using standard phlebotomy techniques. Click here for additional collection instructions.

Test Limitations:

False-positive ASO titers can be due to increased levels of serum beta-lipoprotein produced in liver disease and by "contamination" of serum by Bacillus cereus and Pseudomonas species. ASO is not sensitive for the diagnosis of streptococcal pyoderma.

Test Information:

Components: