Coxiella burnetii (Q-Fever) Antibody IgG, Phase I and II with Reflex to Titer
Also known as: QF G 1/2
Use
The test is used to confirm the presence of the infectious agent Coxiella burnetii, which causes Q fever, in symptomatic patients. It is recommended to test acute and convalescent sera. Acute Q fever is demonstrated by a four-fold rise in phase II IgG titers between two samples collected 3-6 weeks apart. Phase I IgG titers can increase during seroconversion, but in acute infection, the Phase I IgG titer should remain lower than the Phase II titer. A single convalescent serum sample with a Phase II IgG titer greater than 1:128 in a patient who has been sick for more than one week suggests probable acute Q fever. Chronic Q fever is best indicated by a Phase I IgG titer greater than the Phase II titer.
Special Instructions
Not provided.
Limitations
Phase I and phase II IgG titers may remain elevated for months or years after an acute infection or during convalescence. Unacceptable conditions for the test include contaminated, hemolyzed, or severely lipemic specimens.
New York Approved
Methodology
Immunoassay (IFA)
Biomarkers
LOINC Codes
- 48720-7 - C burnet Ph1 IgG Ser Ql IF
- 48719-9 - C burnet Ph2 IgG Ser Ql IF
Result Turnaround Time
1-6 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.4 mL
Container
ARUP standard transport tube
Collection Instructions
Collect using a serum separator tube (SST). Separate serum from cells ASAP or within 2 hours of collection. Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens.
Storage Instructions
Refrigerated.
Causes for Rejection
Contaminated, hemolyzed, or severely lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year (avoid repeated freeze/thaw cycles) |
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