Preferred test for acute or convalescent phase of disease. Acute and convalescent titers often necessary.
- Patient Preparation
- Serum separator tube.
- Specimen Preparation
- Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.1 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 or 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)
|Test Number||Components||Reference Interval|
|0050369||Rickettsia rickettsii (Rocky Mountain Spotted Fever) Antibody, IgG||Less than 1:64: Negative - No significant level of Rickettsia rickettsii Antibody, IgG detected.|
1:64 - 1:128: Low Positive - Presence of Rickettsia rickettsii Antibody, IgG detected, suggestive of current or past infection.
1:256 or greater: Positive - Presence of Rickettsia rickettsii Antibody, IgG suggestive of recent or current infection.
|0050372||Rickettsia rickettsii (Rocky Mountain Spotted Fever) Antibody, IgM||Less than 1:64: Negative - No significant level of Rickettsia rickettsii Antibody, IgM detected.|
1:64 or greater: Positive - Presence of Rickettsia rickettsii Antibody, IgM detected, which may indicate a current or recent infection; however, low levels of IgM antibodies may occasionally persist for more than 12 months post-infection.
The CDC does not use IgM results for routine diagnostic testing of Rocky Mountain Spotted Fever, as the response may not be specific for the agent (resulting in false positives) and the IgM response may be persistent from past infection.
|Component Test Code*||Component Chart Name||LOINC|
|0050369||Rocky Mt Spotted Fever IgG||5307-4|
|0050372||Rocky Mt Spotted Fever IgM||5308-2|
- Rocky Mountain Spotted Fever