Ehrlichia chaffeensis Antibodies, IgG & IgM by IFA
Also known as: E CHAF ABS
Use
This test diagnoses infection from Ehrlichia chaffeensis, which causes human monocytic ehrlichiosis (HME), known as 'spotless' or rashless Rocky Mountain spotted fever. The presence of IgG antibodies suggests current or past infection with Ehrlichia chaffeensis, while IgM antibodies indicate a current or recent infection. The test uses seroconversion between acute and convalescent sera as strong evidence of recent infection, requiring a significant change in titer assessed by IFA for confirmation.
Special Instructions
Test requires serum, preferably collected with a serum separator tube. It should be separated from cells as soon as possible or within 2 hours of collection, and 1 mL of serum should be transferred to an ARUP standard transport tube. Convalescent specimens should be received within 30 days of the acute specimen for parallel testing. Specimen should be marked clearly as acute or convalescent.
Limitations
Presence of IgM antibodies may occasionally persist for more than 12 months post-infection, so a single IgM result should be interpreted with caution. The test requires careful handling and stability considerations, including avoiding repeated freeze/thaw cycles. Contaminated, hemolyzed, or severely lipemic specimens are unacceptable.
New York Approved
Methodology
Immunoassay (IFA)
Biomarkers
LOINC Codes
- 47405-6
- 48850-2
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.4 mL
Container
ARUP standard transport tube
Collection Instructions
Separate serum from cells immediately or within 2 hours of collection.
Causes for Rejection
Contaminated, hemolyzed, or severely lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year |
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