Q Fever IgG and IgM Antibodies (Sendout)
General Information
- Lab Name
- Q Fever IgG and IgM Antibodies (Sendout)
- Lab Code
- RQFP
- Epic Ordering
- Q Fever IgG and IgM Antibodies (Sendout)
- External Test Id
- QFP
- Description
Useful For: Diagnosis of Coxiella burnetii, the causative agent of Q fever.
Ordering Note: For CAST use only. Ordered reflexively when Q Fever Antibody Screen, Reflex to Titer (Sendout) [RQFVRS] is reactive.
- Synonyms
- C Burnetii, Coxiella Burnetii Ab, Coxiella Titer, Febrile Agglutinins, OX-19 (Proteus OX-19 - Weil-Felix), OX-2 (Proteus OX-2 - Weil-Felix), OX-K (Proteus OX-K - Weil-Felix), QFever, QFP, Weil-Felix
- Components
-
Code Name RQFP1G Q Fever Phase I IgG Antibody RQFP2G Q Fever Phase II IgG Antibody RQFP1M Q Fever Phase I IgM Antibody RQFP2M Q Fever Phase II IgM Antibody RQFIN Q Fever IgG and IgM Antibodies Interpretation
Interpretation
- Method
Indirect Immunofluorescence
- Reference Range
- See individual components
- Ref. Range Notes
Reference Values:
Q Fever Phase I Antibody, IgG: <1:16 Q Fever Phase II Antibody, IgG: <1:16 Q Fever Phase I Antibody, IgM: <1:16 Q Fever Phase II Antibody, IgM: <1:16 Interpretation:
Phase I antibody titers greater than or equal to phase II antibody titers are consistent with chronic infection or convalescent phase Q fever.
Phase II antibody titers greater than or equal to phase I antibody titers are consistent with acute/active infection.
A negative result argues against Coxiella burnetii infection. If early acute Q fever infection is suspected, collect a second specimen 2 to 3 weeks later and retest.
In Q fever sera, it is common to see IgG titers of 1:128 or greater to both phase I and phase II antibody titers. IgG class antibody titers appear very early in the disease, reaching maximum phase II titers by week 8 and persisting at elevated titers for longer than a year. Phase I titers follow the same pattern, although at much lower levels, and may not be initially detected until convalescence.
In Q fever sera, it is common to see IgM titers of 1:64 or greater.
IgM class antibody titers appear very early in the disease, reaching maximum phase II titers by week 3 and declining to very low levels by week 14. Phase I titers follow the same pattern, although at much lower levels, and may not be initially detected until convalescence.
- Interferences and Limitations
Cautions: Serologic responses are time dependent. Specimens collected too early in the disease may not have detectable antibody levels. A second specimen collected 2 to 3 weeks may be necessary to detect antibody.
Low level positive titers (ie, <1:256) may remain for prolonged periods of time following resolution of disease.
- Guidelines
Ordering & Collection
- Specimen Type
- Blood
- Collection
-
3 mL blood in a RED TOP tube or GOLD SST
- Handling Instructions
- Quantity
-
requested: 0.5 mL serum
minimum: 0.3 mL serum
Processing
- Processing
Orderable as reflex from Q Fever Antibody Screen, Reflex to Titer (Sendout) [RQFVRS] only.
Stability: Refrigerated: 7 days; Frozen: 7 days: Ambient: Unacceptable.
Reject Due To: Gross hemolysis, gross lipemia, gross icterus.
Performance
- LIS Dept Code
- Sendouts Mayo Lab (RF) (MARF)
- Performing Location(s)
-
Sendout Mayo Clinic Laboratories (Superior Drive)
800-533-17103050 Superior Drive NW
Rochester, MN 55901 - Frequency
- Performed: Monday - Saturday. Report Available: 1-3 days.
- Available STAT?
- No
Billing & Coding
- CPT codes
- 86638x4
- LOINC
- 22211-7
- Interfaced Order Code
- UOW1935