Antistreptolysin O Titer Lab Test

Group A Streptococcal Infection Test

CPT Code(s)

86060

Methodology

Immunoturbidimetric

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 andPseudomonas species. ASO is not sensitive for the diagnosis of streptococcal pyoderma.

Reference Range(s)

Clinical Significance

This test is a sensitive test for recent streptococcal infection. A rise in ASO begins about one week after infection and peaks two to four weeks later. ASO levels do not rise with cutaneous infections. In the absence of complications or reinfection, the ASO level will fall to preinfection levels within 6 to 12 months. Over 80% of patients with acute rheumatic fever and 95% of patients with acute glomerulonephritis due to streptococcihave elevated levels of ASO.

Alternative Name(s)

Streptolysin-O Antibody,Strep A,ASO,Streptococcus, Group A,Strep