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Test Code CTNG Chlamydia/GC PCR LAB7526

Test Method

Polymerase Chain Reaction (PCR); Cepheid, GeneXpert

Performance

Testing performed Monday through Sunday.

Typically completed the same day the specimen arrives at the
testing site.

 

Assay interference may be observed in the presence of blood or mucin with vaginal/endocervical specimens.

The Xpert CT/NG Assay provides qualitative results. No correlation can be drawn between the magnitude of the Ct value and the number of cells in an infected sample.

Xpert CT/NG Assay performance has not been evaluated in patients less than 14 years of age.

Xpert CT/NG Assay performance has not been evaluated in pregnant women, or in patients with a history of hysterectomy.

The Xpert CT/NG Assay has not been evaluated with patients who are currently being treated with antimicrobial agents active against CT or NG.

A negative test result does not exclude the possibility of infection because test results may be affected by improper specimen collection, technical error, specimen mix-up, concurrent antibiotic therapy, or the number of organisms in the specimen which may be below the sensitivity of the tests.

The Xpert CT/NG Assay should not be used for the evaluation of suspected sexual abuse or for other medico-legal indications. Additional testing is recommended in any circumstance when false positive or false negative results could lead to adverse medical, social, or psychological consequences

Specimen Requirement

Vaginal, endocervical,rectal, or pharyngeal swab collected
using Xpert Swab Collection Device (Cepheid #SWAB/G-50) is
required.
 

 

Urine

 

 

Useful For

Detection of Chlamydia trachomatis or Neisseria
gonorrhoeae.

Reference Values

Chlamydia trachomatis PCR: Negative

Neisseria gonorrhoeae PCR: Negative

All positive results are reported to the Iowa
Department of Public Health.

CPT Code Information

0353U - Detection Infectious Agents by Probe Techniques;
Chlaydia trachomatis & GC, amplified probe technique

LOINC Code Information

72828-7 Chlamydia trachomatis and Neisseria gonorrhoeae DNA
panel – Unspecified specimen

Additional Specimen Collection Information

Physician-Collected Endocervical Swab

Collection
Instructions:

  1. Obtain an Xpert Swab Collection Kit.
  2. Remove excess mucus from the cervix and surrounding area using
    the large individually wrapped cleaning swab.
  3. Open the package that contains the pink-capped Xpert Swab
    Transport Reagent tube and individually wrapped collection swab.
    Set the tube aside. Do not expose swab to Xpert CT/NG Swab
    Transport Reagent prior to collection.
  4. Open the collection swab wrapper by peeling open the top of the
    wrapper.
  5. Hold the swab in your hand, placing your thumb and forefinger
    in the middle of the swab shaft.
  6. Insert the collection swab into the endocervical canal. Rotate
    the swab clockwise for 10-30 seconds in the endocervical canal.
    Withdraw the swab carefully.
  7. Unscrew the cap from the transport tube and immediately place
    the specimen collection swab into the transport reagent tube.
  8. Identifying the score-line, break the swab shaft against the
    side of the tube. Discard the top portion of the swab shaft.
  9. Recap the swab transport reagent tube and tighten the cap
    securely. Invert the tube 3-4 times to elute material from the
    swab.
  10. Label the plastic transport tube with the patient name, patient
    identification number, date and time of collection and the
    initials of the nurse who collected the specimen. 

Interfering
Substances:
Interference may be observed in the presence of blood or mucin with
endocervical specimens.

 

Storage:
Swab specimens in transport tubes can be stored at room temperature
or refrigerated for up to 60 days.

 

Patient-Collected Vaginal Swab

 

Collection
Instructions:

  1. Obtain an Xpert Swab Collection Kit. Swabs are not to
    be sent home with patients. They must be collected at the
    healthcare facility.
  2. Open the package that contains the pink-capped Xpert Swab
    Transport Reagent tube and individually wrapped collection swab.
    Set the tube aside. Do not expose swab to Xpert CT/NG Swab
    Transport Reagent prior to collection.
  3. Open the collection swab wrapper by peeling open the top of the
    wrapper. Remove the swab, taking care not to touch the tip or lay
    it down.
  4. Hold the swab in your hand, placing your thumb and forefinger
    in the middle of the swab shaft across the score-line.
  5. Carefully insert the swab into your vagina about two inches
    inside the opening of the vagina.
  6. Gently rotate the swab for 10-30 seconds. Ensure the swab
    touches the walls of the vagina so that moisture is absorbed onto
    the swab. Withdraw the swab and continue to hold it in your
    hand.
  7. Unscrew the cap from the transport tube and immediately place
    the specimen collection swab into the transport reagent tube.
  8. Identifying the score-line, break the swab shaft against the
    side of the tube. Discard the top portion of the swab shaft.
  9. Recap the swab transport reagent tube and tighten the cap
    securely.
  10. Return the tube as instructed to your doctor, nurse, or
    care-provider. The Health Care Provider should label the plastic
    transport tube with the patient name, patient identification
    number, date and time of collection and the initials of
    employee who assisted with the collected the specimen.

Interfering
Substances:
Interference may be observed in the presence of blood or mucin with
vaginal specimens.

 

Storage:
Swab specimens in transport tubes can be stored at room temperature
or refrigerated for up to 60 days.

 

Clinician Collected Rectal Swab

 

Collection
Instructions:

  1. Obtain an Xpert Swab Collection Kit.
  2. Discard the larger swab.
  3. Open the package that contains the pink-capped Xpert Swab
    Transport Reagent tube and individually wrapped collection swab.
    Set the tube aside. Do not expose swab to Xpert CT/NG Swab
    Transport Reagent prior to collection.
  4. Open the collection swab wrapper by peeling open the top of the
    wrapper.
  5. Hold the swab in your hand, placing your thumb and forefinger
    in the middle of the swab shaft.
  6. Carefully insert the swab approximately 1 cm beyond the anal
    sphincter (so that the fiber tip is no longer visible) and rotate
    gently. Withdraw the swab carefully.
  7. Unscrew the cap from the transport tube and immediately place
    the specimen collection swab into the transport reagent tube.
  8. Identifying the score-line, break the swab shaft against the
    side of the tube. Discard the top portion of the swab shaft.
  9. Recap the swab transport reagent tube and tighten the cap
    securely. Invert the tube 3-4 times to elute material from the
    swab.
  10. Label the plastic transport tube with the patient name, patient
    identification number, date and time of collection and the
    initials of the nurse who collected the specimen. 

Clinician Collected Pharyngeal Swab

 

Collection
Instructions:

  1. Obtain an Xpert Swab Collection Kit.
  2. Discard the larger swab.
  3. Open the package that contains the pink-capped Xpert Swab
    Transport Reagent tube and individually wrapped collection swab.
    Set the tube aside. Do not expose swab to Xpert CT/NG Swab
    Transport Reagent prior to collection.
  4. Open the collection swab wrapper by peeling open the top of the
    wrapper.
  5. Hold the swab in your hand, placing your thumb and forefinger
    in the middle of the swab shaft.
  6. Instruct the patient to open mouth widely. Position tongue
    toward the bottom of the mouth. Swab areas of the pharynx (tonsil,
    posterior wall, uvula).
  7. Unscrew the cap from the transport tube and immediately place
    the specimen collection swab into the transport reagent tube.
  8. Identifying the score-line, break the swab shaft against the
    side of the tube. Discard the top portion of the swab shaft.
  9. Recap the swab transport reagent tube and tighten the cap
    securely. Invert the tube 3-4 times to elute material from the
    swab.
  10. Label the plastic transport tube with the patient name, patient
    identification number, date and time of collection and the
    initials of the nurse who collected the specimen. 

Urine Specimens

Collection
Instructions:

  1. The patient should not have urinated for at least 1 hour prior
    to specimen collection.
  2. Female patients should not cleanse the labial area prior to
    specimen collection.
  3. Male patients should not cleanse the tip of the penis prior to
    specimen collection.
  4. Direct patient to provide first-catch urine into a urine
    collection cup free of any preservatives.
  5. Label the urine cup with the patient name, patient
    identification number, date & time of collection and the
    initials of the nurse who collected the specimen.