ARUP's Laboratory Test Directory

St. Louis Encephalitis Antibody, IgM by IFA, Serum : 0098732

Mnemonic: STL M SER

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: 0.15 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: Plasma. Contaminated, heat-inactivated, 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: This test is intended to be used as a semi-quantitative means of detecting St. Louis virus-specific IgM in serum samples in which there is a clinical suspicion of St. Louis virus infection.  A positive result for IgM may suggest current or recent infection.  This test should not be used solely for quantitative purposes, nor should the results be used without correlation to clinical history or other data.  Because other members of the Flaviviridae family, such as West Nile virus, show extensive cross-reactivity with St. Louis virus, serologic testing specific for these species should also be performed.
CPT Code(s): 86653
Cross References: Encephalitis Antibody, St. Louis (St. Louis Encephalitis Antibody, IgM by IFA, Serum)