ARUP's Laboratory Test Directory

Eastern Equine Encephalitis Antibody, IgG by IFA, Serum : 0050509

Mnemonic: EASTERN

Methodology: Semi-Quantitative Indirect Fluorescent Antibody
Performed: Tue, Fri
Reported: 1-5 days
Specimen Required: 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: Severely contaminated, hemolyzed, or severely lipemic specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference Interval:
Less than 1:16
Interpretive Data: A positive result for IgG may suggest current or past infection. Eastern equine encephalitis and western equine encephalitis viruses are both related and will show cross-reactivity. Initial infection by one of these viruses will show a specific rise in titer which is higher than titers against any other viruses of the group. A subsequent infection by another virus within this group, however, will boost the titer against the initial infecting virus (anamnestic response) and make a specific diagnosis difficult.
CPT Code(s): 86652
Cross References: Encephalitis Antibody (Eastern Equine Encephalitis Antibody, IgG by IFA, Serum)