Legionella pneumophila Antibody (Types 1-6), IgG by IFA
Ordering Recommendation
Semi-Quantitative Indirect Fluorescent Antibody
1-4 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
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: 0.1 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
Unacceptable Conditions
Contaminated, hemolyzed, or severely lipemic specimens.  
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)  
Reference Interval
<1:128  Negative -  No significant level of Legionella pneumophila Type 1-6 IgG antibody detected.
1:128 Equivocal - Questionable presence of Legionella pneumophila Type 1-6 IgG antibody detected. Repeat testing in 10-14 days may be helpful.
1:256 or greater Positive -  Presence of Legionella pneumophila Type 1-6 IgG antibody 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 on two appropriately timed specimens where both tests are done in the same laboratory at the same time. This assay may detect infection by any of the serotypes 1-6. The CDC and many state health laboratories recommend testing only for antibody to Legionella pneumophila Type 1. For equivocal or positive IFA results, the CDC protocol suggests follow-up testing for Legionella pneumophila antibody Type 1.  
For follow-up testing on equivocal or positive results, refer to Legionella pneumophila Antibody (Type 1), IgG by IFA (0050376).
CPT Code(s)
Component Test Code*Component Chart NameLOINC
0050365Legionella Pneumophila 1-6,IgG21362-9
* 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.
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