Order Code SFGP Spotted Fever Group Antibody, IgG and IgM, Serum
Reporting Name
Spotted Fever Group Ab, IgG, IgM, SPerforming Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumSpecimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Specimen Minimum Volume
0.2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 14 days |
Reference Values
IgG: <1:64
IgM: <1:64
Reference values apply to all ages.
Day(s) Performed
Monday through Friday
CPT Code Information
86757 x 2
Testing Algorithm
For more information see Acute Tick-Borne Disease Testing Algorithm.
Special Instructions
Useful For
Aiding in the diagnosis of spotted fever group rickettsial infections
Method Description
Substrate slides containing antigen wells for measuring antibodies to both groups of Rickettsia (spotted fever and typhus) are obtained. The indirect immunofluorescence assay is a 2-stage "sandwich" procedure. In the first stage, the patient serum is diluted in yolk sac diluent. The diluted serum is placed on the slide in contact with the substrate and incubated. Following incubation, the slide is washed in buffered saline, which removes unbound serum antibodies. In the second stage, each antigen well is overlaid with fluorescein-labeled antibody to human IgG or IgM. The slide is incubated allowing antigen-antibody complexes to react with the fluorescein-labeled antihuman IgG or IgM. After the slide is washed, dried, and mounted, it is examined using fluorescence microscopy. Positive reactions appear as rickettsial bodies exhibiting bright apple-green cytoplasmic fluorescence against a background of orange to red yolk sac matrix. Semiquantitative end point titers are obtained by testing serial dilutions of positive specimens.(Package inserts: Rickettsia IFA IgM. DiaSorin Molecular LLC; 05/2018; Rickettsia IFA IgG. DiaSorin Molecular LLC; 05/2018)
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Method Name
Immunofluorescence
Forms
If not ordering electronically, complete, print, and send Infectious Disease Serology Test Request (T916) with the specimen.