Coxiella burnetii (Q-Fever) Antibody IgG, Phase I and II with Reflex to Titer
Ordering Recommendation
Confirm infectious agent as C. burnetii (Q-fever) in symptomatic patients. Recommend testing of acute and convalescent sera.
New York DOH Approval Status
Specimen Required
Serum separator tube (SST).
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP standard transport tube. (Min: 0.4 mL) Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens. Mark specimens plainly as "acute" and "convalescent."
Refrigerated.
Contaminated, hemolyzed, or severely lipemic specimens.
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Methodology
Qualitative Indirect Fluorescent Antibody (IFA)
Performed
Mon, Wed, Fri
Reported
1-6 days
Reference Interval
Test Number | Component | Reference Interval |
---|---|---|
C. burnetii (Q-Fever) Ab, Phase I IgG | Negative | |
C. burnetii (Q-Fever) Ab, Phase II IgG | Negative |
Interpretive Data
Acute Q fever is best demonstrated by a four-fold rise in phase II IgG titers when comparing two serum samples collected 3-6 weeks apart, and testing is performed in the same laboratory at the same time. Phase I IgG titers can increase during seroconversion. However, in the case of acute infection, the phase I IgG titer should remain lower than the phase II titer. In the absence of an acute sample, a single convalescent serum sample with a phase II IgG titer greater than 1:128 in a patient who has been ill greater than 1 week, indicates probable acute Q fever.
Chronic Q fever is best demonstrated by a phase I IgG titer greater than the phase II IgG titer. Phase I and phase II IgG titers may remain elevated for months.
FDA
Note
If either C. Burnetii Abs IgG Phase I and/or Phase II result is indeterminate or positive, then titer(s) will be added. Additional charges apply.
Hotline History
Hotline History
CPT Codes
86638 x2; if reflexed add 86638 per titer
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2012626 | C. Burnetii Abs, IgG Phase I Screen | 48720-7 |
2012628 | C. Burnetii Abs, IgG Phase II Screen | 48719-9 |
Aliases
- Coxiella burnetii
- Coxiella Titer
- Q Fever Phases I and II antibody