Coxiella burnetii / Q Fever Phase 2 IgG antibody ELISA Kit

Arigo Biolaboratories

Coxiella burnetii / Q Fever Phase 2 IgG antibody ELISA Kit

23

~ 1 hours

ELISA

Cut - off

Intra-Assay CV: less than 9%Inter-Assay CV: less than 7%

diagn. 100%

~2 hour

Research Use Only

HRP

The reference standard test for the serologic diagnosis of acute Q fever is the indirect immunofluorescence antibody (IFA) using C. burnetii antigen, performed on paired serum samples to demonstrate a significant (fourfold or more) rise in antibody titers. The first sample should be taken as early in the disease as possible, preferably in the first week of symptoms, and the second sample should be taken 3 to 6 weeks later. In most cases of Q fever, the first IgG IFA titer is typically low, or negative, and the second typically shows a fourfold or greater increase in IgG antibody levels. A negative test during the first week of illness does not rule out Q fever as a cause of illness. There are two distinct antigenic phases (phase I and phase II) to which humans develop antibody responses. In acute infection, an antibody response to C. burnetii phase II antigen is predominant and is higher than antibody levels to phase I antigen; the reverse is true in chronic infection which is associated with a rising phase I IgG titer that may be higher than phase II IgG. IgM antibodies usually rise at the same time as IgG, near the end of the first week of illness, and remain elevated for months or longer and therefore provide limited diagnostic value on their own. Furthermore, IgM antibodies are less specific than IgG antibodies and more likely to result in a false positive. For these reasons, physicians requesting IgM serologic titers should also request concurrent IgG titers.

2°C to 8°C

41116100