2-4 days after setup at PeaceHealth Laboratories’ reference lab.
Specimen Collection Details
One 7.5 mL serum separator tube (SST).
Allow to clot. Centrifuge, separate serum from cells and immediately pour into a plastic vial.
48 hours ambient, 14 days refrigerated, or 1 year frozen.
1 mL serum.
0.5 mL serum.
The majority of group A streptococci produce significant quantities of DNase-B, while most other groups of streptococci do not. High levels of neutralizing antibody to DNase-B are commonly found in patients following a group A streptococcal infection. Since it persists longer than other streptococcal antibodies (2-3months), it is the preferred test in patients with chorea suspected to be due to rheumatic fever. Since it is not influenced by the site of infection, DNase-B antibody is more reliable than the streptolysin O antibody (ASO) test in providing evidence for streptococcal infection in patients with post-impetigo glomerulonephritis. Elevated titers are strongly suggestive of recent or current infection with group A streptococci. Fourfold increases in titer between acute and convalescent samples taken approximately 2 weeks apart are confirmatory.