Use

This test is a sensitive indicator of recent Group A streptococcal infection. ASO titers begin to rise approximately one week post‑infection, peaking two to four weeks later. Although useful in diagnosing recent infections, ASO does not increase in cutaneous streptococcal infections. In uncomplicated cases, ASO levels gradually decline over 6 to 12 months. Elevated ASO titers are observed in over 80% of acute rheumatic fever cases and about 95% of acute post‑streptococcal glomerulonephritis cases, underscoring its clinical utility. This overview is based on Quest diagnostics‑associated lab info.