Lab Dept:

Microbiolgy/Virology

Test Name:

HUMAN METAPNEUMOVIRUS PCR

General Information

Lab Order Codes:

MPVP

Synonyms:

hMPV PCR; Metapneumovirus PCR; Respiratory viruses, human Metapneumovirus (hMPV) PCR; Virus, PCR for human Metapneumovirus (hMPV)

CPT Codes:

87798 – Amplified probe technique, each organism

Test Includes:

Detection of human metapneumovirus in patients exhibiting symptoms of acute upper and /or lower respiratory tract infections by RT-PCR (Reverse Transcription Polymerase Chain Reaction). Detection of influenza virus types A and B and RSV can be performed using the same specimen if requested.

Logistics

Lab Testing Sections:

Molecular Diagnostics, Mpls Campus

Phone Number:

612-813-7103

Test Availability:

Specimens accepted daily, 24 hours

Turnaround Time:

12 – 24 hours

Special Instructions:

Requisition must state specific site of specimen and date/time of collection.

Specimen

Specimen Type:

Bronchoalveolar lavage (BAL) specimens; Nasopharyngeal washings; nasopharyngeal aspirates; 2 flexible-shaft dacron NP swabs. Do not use calcium alginate swabs.

Container:

Sterile screw cap container; swab transport media. Caution: containers with tubing tend to leak compromising the specimen.

Volume:

1 – 2 mL nasal washings, nasal aspirates or BAL; 2 NP swabs

Collection:

Nasopharyngeal Washings

1. Tilt patients head back at a 70 ° angle.
2. Insert rubber bulb syringe containing 1 – 2 mL sterile saline until it occludes the nostril.
3. Collect specimen (minimum: 1 mL) with one complete squeeze and release bulb.
4. Repeat in other nostril.
5. Dispense the specimen into a sterile screw cap container and transport to the lab immediately.

If specimen cannot be transported to the lab immediately, place 1 – 2 mL of specimen in viral transport media (VTM) and refrigerate.

Nasal Aspiration

1. Prepare suction set up on low to medium suction.
2. Wash hands.
3. Put on protective barriers (e.g., gloves, gown, mask).
4. Place child supine and obtain assistant to hold child during procedure.
5. Attach luki tube to suction tubing and #6 French suction catheter.
6. Insert catheter into nostril and pharynx without applying suction.
7. Apply suction as catheter is withdrawn.
8. If necessary, suction 0.5 – 1 mL of normal saline through catheter in order to clear the catheter and increase the amount of specimen in the luki tube.
9. Carefully transfer specimen to a screw cap container.

If specimen cannot be transported to the laboratory immediately, place 1 – 2 mL of specimen in viral transport media (VTM) and refrigerate.

NP swabs (2)

1. Carefully insert a flexible-shaft dacron swab containing a dry tip into the nasopharyngeal cavity until resistance is encountered.
2. Rotate the swab slowly on the nasopharyngeal membrane for 5 – 10 seconds to absorb secretions.
3. Remove the swab, place in swab transport medium and send to the lab immediately.

If specimen cannot be transported to the laboratory immediately, cut swabs into viral transport media (VTM) and refrigerate.

Bronchoscopy

1. Specimen obtained by physician through the biopsy channel of the bronchoscope.
2. Transfer 1 – 2 mL of sample into a luki tube or sterile container.

Special Processing:

Lab Staff: Place specimen into viral transport media (M4 VTM) upon arrival in laboratory.

Transport/Storage:

Transport to the Laboratory immediately to maintain specimen integrity. Specimens can be stored at refrigerated temperature (2 – 8º C) for up to 72 hours before processing.

Sample Rejection:

Specimen with a transit time exceeding 1 hour after collection without refrigeration; specimen not submitted in appropriate transport container; dry swabs; improperly labeled specimen; insufficient volume; leaking or non-sterile containers.

If an unacceptable specimen is received, the patient’s caregiver will be notified and another specimen will be requested before the specimen is discarded

Interpretive

Reference Range:

No human metapneumovirus detected by PCR

Unresolved results due to PCR inhibition are inconclusive. Consider repeat collection if clinically indicated.

Critical Values:

N/A

Limitations:

• Blood, excessive nasal secretions/mucus, decongestants and substances used to relieve nasal dryness or irritation may inhibit PCR and give unresolved results.
• There is a risk of false negative results if specimens are improperly collected, transported or stored
• Low levels of virus shedding may yield a false negative result.

Methodology:

Reverse Transcription Polymerase Chain Reaction (RT - PCR)

References:

Pro hMPV+ Instructions for Use, PIH27 V2.1 March 2010, GenProbe Prodesse, Inc., W229 N1870 Westwood Drive, Waukesha, WI 53186

Miller, J. Michael (1999) A Guide To Specimen Management in Clinical Microbiology, American Society for Microbiology, Washington, D.C, pg 100

Miller, J. Michael, Krisher, K. and Holmes, H.T. (2007) General Principles of Specimen Collection and Handling In P.R. Murray et al., (ed.), Manual of Clinical Microbiology, 9th edition, American Society for Microbiology, Washington, D.C., pg 50

Updates:

1/10/2011: Addition of BAL specimen type.
11/30/2011: BAL specimen type validated in 2011.