Ehrlichia chaffeensis Antibody, IgG by IFA
0051004
 
Ordering Recommendation
Mnemonic
E CH G
Methodology
Semi-Quantitative Indirect Fluorescent Antibody
Performed
Tue, Fri
Reported
1-5 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
 
Collect
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: 0.05 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
Refrigerated.  
Unacceptable Conditions
Contaminated, hemolyzed, or severely lipemic specimens.  
Remarks
 
Stability
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)  
Reference Interval
< 1:64 Negative-No significant level of Ehrlichia chaffeensis IgG antibody detected.
1:64-1:128 Equivocal-Questionable presence of Ehrlichia chaffeensis IgG antibody detected. Repeat testing in 10-14 days may be helpful.
≥1:256 Positive-Presence of IgG antibody to Ehrlichia chaffeensis detected, suggestive of current or past infection.
Interpretive Data
Seroconversion between acute and convalescent sera is considered strong evidence of recent infection. The best evidence for infection is a significant change (fourfold difference in titer) on two appropriately timed specimens, where both tests are done in the same laboratory at the same time.

See Compliance Statement B: www.aruplab.com/CS
Note
Human ehrlichiosis is a tick-borne disease caused by rickettsial-like agents. Two forms, human monocytic ehrlichiosis (HME) and human granulocytic ehrlichiosis (HGE), have been described. HME is often referred to as "spotless" or rashless Rocky Mountain spotted fever, and has been reported in various regions of the United States. The causative agent of HME has been identified as Ehrlichia chaffeensis. Infected individuals produce specific antibodies to E. chaffeensis, which can be detected by an immunofluorescent antibody (IFA) test.
CPT Code(s)
86666
Components
Component Test Code*Component Chart Name
0051004Ehrlichia chaffeensis Antibody, IgG
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, contact interface support at interface.support@aruplab.com.
Cross References
  • E. Chaffeensis
  • HME (Human Monocytic Ehrlichiosis)
  • Tick Borne Diseases