B. pertussis and B. parapertussis PCR (Sendout)

Useful For: Diagnostic test for the detection of Bordetella pertussis or Bordetella parapertussis.

The CDC notes: "Clinicians should strongly consider treating prior to test results if clinical history is strongly suggestive or patient is at risk for severe or complicated disease (e.g., infants)."

B. pertussis PCR is preferred to culture when a diagnostic test is required and detects roughly twice as many cases as culture. B pertussis DNA can be detected up to 4 weeks, or longer after symptom onset. Refer to the CDC website for additional information on testing for B. pertussis.

Reference Ranges:

Interpretation: A positive result indicates the presence of DNA from Bordetella pertussis or B parapertussis. In some cases, a patient may test positive for both B pertussis and B parapertussis. Cross-reactivity with B holmesii and B bronchiseptica may occur with the B pertussis assay (see Cautions).

A negative result indicates the absence of detectable B pertussis and B parapertussis DNA in the specimen but does not negate the presence of organism or active or recent disease (known inhibition rate of <1%) and may occur due to inhibition of PCR, sequence variability underlying primers and/or probes, or the presence of B pertussis or B parapertussis in quantities less than the limit of detection of the assay. Additionally, patients presenting late after symptom onset may test negative; in such cases, testing for B pertussis antibody, IgG, in serum may be considered.

Cautions:

Cross-reactivity with Bordetella holmesii may occur with the B pertussis PCR assay. The prevalence of B holmesii is relatively low, with positivity in <1% of nasopharyngeal swabs.¹ Please note that B holmesii has been associated with pertussis-like symptoms.¹

Cross-reactivity of the B pertussis assay has been demonstrated with a limited number of Bordetella bronchiseptica isolates. The prevalence of the insertion sequence target, IS481, has been reported to be between 1% and 5% in B bronchiseptica isolates.

This assay is not recommended for screening asymptomatic individuals who may carry B pertussis or parapertussis.

This assay is not recommended for follow up of patients previously diagnosed with pertussis (ie, as a test of cure).

Some B pertussis acellular vaccines (ie, Pentacel, Daptacel, Adacel) contain PCR detectable DNA. Contamination of specimens with vaccine can cause false-positive B pertussis PCR results. Specimens should not be collected or processed in areas that are exposed to B pertussis vaccine material.

Collection Note: The high sensitivity of amplification by PCR requires the specimen to be processed in an environment in which contamination of the specimen by Bordetella pertussis or Bordetella parapertussis DNA is unlikely.

Collect one of the following:

• Nasopharyngeal Swab (Culture Swab - Liquid Stuarts/Single Swab): Rayon swab with an aluminum shaft placed in transport medium such as a green-top nasopharyngeal swab (rayon mini-tip) with Stuart's media (no charcoal) (Mayo collection T515), or Stuart's with charcoal, or Amies with or without charcoal (Transwab Nasopharyngeal with Charcoal System).
  • Swab transport containers without charcoal must contain a pledget saturated with either Stuart's or Amies liquid media. Clear semi-solid/solid media is gel and will be rejected.
  • Other swab or media types may be inhibitory to PCR testing and will be rejected.
• Nasal Wash in sterile container: 0.5 mL nasopharyngeal (not throat) aspirate/wash or nasal aspirate/wash in a sterile container with a screw top cap (no transport media).

Reject Due To: Nose, nasal, or throat swab; calcium alginate or cotton-tipped swab; swab sent in gel transport medium, viral/universal transport medium, or Regan Lowe media; ESwab; swabs with solid plastic shaft; dry swab.

Mayo Special Collection Container: T515 (Rayon Mini-Tip Swab)

• UW Medicine Locations: Obtain Mayo swabs from the Specimen Processing Services lab at your facility.
  • UWMT: Room NW-220
  • UWNW: A200
  • HMC: Room GWH-47

Outside Laboratories: Refrigerate sample in original container.

• Contact Client Support Services at (206) 520-4600 or commserv@uw.edu to obtain swabs [Mayo Supply: T515].

Stability: Refrigerated (preferred): 7 days; Ambient: 7 days; Frozen: 7 days.

Reject Due To: Nose, nasal, or throat swab; calcium alginate or cotton-tipped swab; swab sent in gel transport medium, viral/universal transport medium, or Regan Lowe media; ESwab; swabs with solid plastic shaft; dry swab.

Refrigerate sample in original collection container.

Result-at-Entry:

• RBPSPC (B. pertussis and B. parapertussis specimen): [Enter appropriate specimen type code below.]

Specimen Codes:

• NPS (Nasopharyngeal swab)
• NW (Nasal Wash)

Sendouts:

• Order Mayo Test: BPRPV.
• Interfaced: Yes. [Interface: 601; Department: MARF]

Stability: Refrigerated (preferred): 7 days; Ambient: 7 days; Frozen: 7 days.

Reject Due To: Nose, nasal, or throat swab; calcium alginate or cotton-tipped swab; swab sent in gel transport medium, viral/universal transport medium, or Regan Lowe media; ESwab; swabs with solid plastic shaft; dry swab.

Mayo Special Collection Container: T515 (Rayon Mini-Tip Swab)