Crystal® VC Rapid Diagnostic Test (RDT) Procedure

IMPORTANT: Wear appropriate personal protective equipment while performing this test.

  1. Label 5 ml test tube with patient identifier. Set aside.
  2. Ensure the reagent bottle is intact and solution is not turbid or discolored. Discard bottle if unsatisfactory.
  3. Unscrew the sample processing vial and add sample.
    1. For solid, semisolid, or viscous stool, use the sampling stick to collect a small portion of stool from two or more areas in the sample and insert in the sample processing vial. NOTE: “Stab” do not “scoop” to avoid picking up particulate matter that may clog the dipstick membrane.
    2. For liquid stool, use transfer pipette to add 2 drops of sample to the sample processing vial.
  4. Tightly recap sample processing vial and shake to mix contents.
  5. Break the outer end of the cap from the sample processing vial.
  6. Dispense 4 drops of processed sample into labeled 5 ml test tube.
  7. Carefully open aluminum pouch along perforated line.
  8. Inspect contents. REMINDER: Only touch the top of the dipstick.
    1. Check dipstick for damage (e.g., no tears, splits, discoloration).
    2. Ensure the pouch contains desiccant that has not changed white in color.
    3. Discard dipstick if damaged, or if desiccant is missing or changed to white in color.
  9. Label top of dipstick with patient identifier.
  10. Place the dipstick in the test tube with the arrows facing DOWN.
  11. Confirm the end of the dipstick (“the dipping area”) is submerged in the processed sample. NOTE: The arrows should remain above the level of the sample.
  12. Wait 15-30 minutes, remove dipstick and read the result. (See table below for results interpretation.)
  13. Place all waste in a double-lined plastic bag labeled “Biohazard.”
Results Interpretation
Interpretation* Pinkish red band observed
O1 O139 Control
A. Vibrio cholerae O139 detected + +
B. Vibrio cholerae O1 detected + +
C. Vibrio cholerae O1 and O139 detected + + +
D. Vibrio cholerae O1 and O139 not detected +
E. Invalid results + or – + or –

*Control band must appear for the result to be considered valid.

diagram showing how to use the bottles.

Schematic View of Dipstick

diagram of a dipstick showing where to touch, where to ID, where the bands will appear, where to insert with the arrows pointing down, and the dipping area.
visual representation showing the control band with valid results and invalid results.

Schematic Interpretation of Results