Entamoeba histolytica Antigen Rapid Test (ICT/Lateral Flow Assay)


1. Objective

To rapidly detect antigens of Entamoeba histolytica in human stool samples using a lateral flow immunochromatographic test (ICT), providing a quick diagnosis of amebiasis.

2. Principle

The test utilizes monoclonal antibodies specific to E. histolytica antigens, immobilized on a nitrocellulose strip inside a plastic cassette.

  • When stool extract is added, if the E. histolytica antigen is present, it binds to gold-labeled antibodies in the conjugate pad and migrates by capillary action.

  • A visible colored test line forms at the "T" (test) line if the antigen is present.

  • A control line (C) appears in all valid tests to confirm the test worked properly.

3. Materials

  • Entamoeba histolytica rapid test cassette (ICT device)

  • Sample buffer (provided in kit)

  • Stool collection container

  • Dropper or swab stick

  • Timer or stopwatch

  • Gloves and PPE

  • Biohazard disposal container

4. Procedure

  • Collect stool sample in a clean container.

  • Prepare sample by mixing a small amount in the provided buffer tube.

  • Add 3–4 drops of the mixed solution into the sample well of the test cassette.

  • Wait for 10–15 minutes (as per manufacturer's instructions).

  • Interpret results within the specified time frame.

5. Result Interpretation

  • Positive: Two colored lines appear—one in the test region (T) and one in the control region (C).

  • Negative: Only one colored line appears in the control region (C).

  • Invalid: No control line appears; test must be repeated.

6. Uses

  • Rapid diagnosis of intestinal amebiasis caused by E. histolytica.

  • Ideal for point-of-care testing, travel clinics, and field diagnostics.

  • Especially useful in resource-limited settings due to its simplicity and speed.

7. Conclusion

The Entamoeba histolytica Antigen Rapid Test is a quick, easy-to-use, and cost-effective method to screen for amebiasis. Though not as sensitive as ELISA, it provides reliable results within minutes without requiring laboratory equipment.


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