Ordering Recommendation

Confirm infectious agent as C. burnetii (Q-fever) in symptomatic patients. Recommend testing of acute and convalescent sera.


QF G 1/2


Semi-Quantitative Indirect Fluorescent Antibody


Mon, Wed, Fri


1-6 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Serum separator tube (SST).

Specimen Preparation

Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 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."

Storage/Transport Temperature


Unacceptable Conditions

Contaminated, hemolyzed, or severely lipemic specimens.


After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

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

Single phase II IgG titers of 1:256 and greater are considered evidence of C. burnetii infection at some time prior to the date of the serum specimen. Phase I antibody titers of 1:16 and greater are consistent with chronic infection or convalescent phase of Q-fever.

Compliance Category



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


CPT Codes

86638 x2; if reflexed add 86638 per titer


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
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • Coxiella burnetii
  • Coxiella Titer
  • Q Fever Phases I and II antibody
Coxiella burnetii (Q-Fever) Antibody IgG, Phase I and II with Reflex to Titer