ARUP's Laboratory Test Directory

Entamoeba histolytica (amebiasis), Antibody, IgG : 0050070

Mnemonic: AMB

Methodology: Semi-Quantitative Enzyme-Linked Immunosorbent Assay
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: 0.1 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: Refrigerated.

Unacceptable Conditions: 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:
0.79 IV or less: Negative - No significant level of detectable E. histolytica IgG antibody.
0.80-1.19 IV: Equivocal - Repeat testing in 10-14 days may be helpful.
1.20 IV or greater: Positive - IgG antibody to E. histolytica detected, suggestive of a 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.
Note: In the case of extraintestinal complications, a positive antibody can indicate amebiasis even though stool findings are negative.
CPT Code(s): 86753
Cross References: Amebiasis histolytica Antibody (Entamoeba histolytica (amebiasis), Antibody, IgG) , E. histolytica Antibody (Entamoeba histolytica (amebiasis), Antibody, IgG)