Giardia Antigen Detection


Send Email

Recipient(s) will receive an email with a link to 'Giardia Antigen Detection' and will have access to the topic for 7 days.

Subject: Giardia Antigen Detection

(Optional message may have a maximum of 1000 characters.)


Definition and Use

  • The Giardia antigen detection test is used for the identification of Giardia lamblia in stool specimens. It is used to evaluate diarrheal disease in patients at risk for giardiasis. Giardia EIA has a very high sensitivity (near 100%) and specificity (near 100%) compared with a series of stool O & P examinations.

  • Turnaround time: 24–48 hours.


  • Expected results: Negative.


  • Several specimens may be required in patients with light infection. Repeat testing improves sensitivity of detection. A series of O & P examinations is recommended in patients with repeatedly negative immunoassays in whom parasitic infection is still suspected.

  • A common pitfall is submission of the incorrect type of specimen for the assay. To perform immunoassays accurately, the correct specimen type (preserved or fresh) and procedures, as specified in kit instructions, must be followed exactly.

Suggested Readings

CLSI. Procedures for the Recovery and Identification of Parasites from the Intestinal Tract; Approved Guideline, 2nd ed. CLSI document M28-A2. Wayne, PA: Clinical and Laboratory Standards Institute; 2005.
Garcia  LS. Diagnostic Parasitology, 5th ed. Washington, DC: ASM Press; 2007.