Ordering RecommendationRecommendations when to order or not order the test. May include related or preferred tests.
Preferred test for acute or convalescent phase of disease. Acute and convalescent titers often necessary.
MnemonicUnique test identifier.
RMSF G/M
MethodologyProcess(es) used to perform the test.
Semi-Quantitative Indirect Fluorescent Antibody
PerformedDays of the week the test is performed.
Sun-Sat
ReportedExpected turnaround time for a result, beginning when ARUP has received the specimen.
1-3 days
New York DOH Approval StatusIndicates test has been approved by the New York State Department of Health.
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect
Serum Separator Tube (SST).
Specimen Preparation
Separate 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.
Storage/Transport Temperature
Refrigerated.
Unacceptable Conditions
Contaminated, hemolyzed, or severely lipemic specimens.
Remarks
Mark specimens plainly as "acute" or "convalescent."
Stability
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference IntervalNormal range/expected value(s) for a specific disease state. May also include abnormal ranges.
Negative - No significant level of IgM antibody detected.
1:64 or greater
Positive - Presence of IgM antibody 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.
Interpretive DataBackground information for test. May include disease information, patient result explanation, recommendations, details of testing, associated diseases, explanation of possible patient results.
Antibody reactivity to Rickettsia rickettsii antigen should be considered Spotted Fever group reactive. Other organisms within the group include R. akari, R. conorrii, R. australis, and R. sibirica.
Seroconversion, a fourfold or greater rise in antibody titer, between acute and convalescent sera is considered strong evidence of recent infection. Acute-phase specimens are collected during the first week of illness and convalescent-phase samples are generally obtained 2-4 weeks after resolution of illness. Ideally these samples should be tested simultaneously at the same facility. If the sample submitted was collected during the acute-phase of illness, submit a marked convalescent sample within 25 days for paired testing.
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.
Compliance Category
FDA
NoteAdditional information related to the test.
Hotline History
N/A
CPT CodesThe American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. The codes reflect our interpretation of CPT coding requirements based upon AMA guidelines published annually. CPT codes are provided only as guidance to assist clients with billing. ARUP strongly recommends that clients confirm CPT codes with their Medicare administrative contractor, as requirements may differ. CPT coding is the sole responsibility of the billing party. ARUP Laboratories assumes no responsibility for billing errors due to reliance on the CPT codes published.
* 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.
AliasesOther names that describe the test. Synonyms.
Rickettsia
RMSF
Rocky Mountain Spotted Fever
Rickettsia rickettsii (Rocky Mountain Spotted Fever) Antibodies, IgG & IgM by IFA