Real-time PCR by Abbott Alinity Resp-4-Plex
The Alinity m Resp-4-Plex assay is a multiplex real-time reverse transcription (RT) polymerase chain reaction (PCR) test intended for the simultaneous qualitative detection and differentiation of RNA from SARS-CoV-2, influenza A virus (flu A), influenza B virus (flu B), and/or Respiratory Syncytial Virus (RSV).
The Alinity m Resp-4-Plex assay is a multiplex real-time reverse transcription (RT) polymerase chain reaction (PCR) test for use with the automated Alinity m System for the qualitative detection and differentiation of RNA from flu A, flu B, RSV, and SARS-CoV-2 in respiratory specimens from individuals suspected of a respiratory viral infection consistent with COVID-19. Testing is limited to laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. Åò 263a, that meet requirements to perform moderate or high complexity tests.
The Alinity m Resp-4-Plex assay is only for use under the Food and Drug Administration’s Emergency Use Authorization.
Based on in-house testing, the lower limit of detection for Influenza A is 36 copies/ml, for Influenza B is 11 copies/ml, for RSV is 17 copies/ml and for SARS-CoV-2 is 9 copies/ml.
Test performance varies by site of sample collection. In situations where maximum sensitivity is needed for patient care or infection prevention, a nasopharyngeal swab sample is recommended.
Positive results are indicative of active infection but do not rule out bacterial infection or co-infection with other pathogens not detected by the test. Clinical correlation with patient history and other diagnostic information is necessary to determine patient infection status. The agent detected may not be the definite cause of disease.
Negative results do not preclude influenza A, influenza B, RSV, or SARS-CoV-2 infection and should not be used as the sole basis for patient management decisions. Negative results must be combined with clinical observations, patient history, and epidemiological information.
Recent patient exposure to FluMist or other attenuated influenza vaccines may cause inaccurate positive results for flu A and flu B due to the presence of attenuated viruses.
Interference was observed for RSV when evaluated with FluMist. Recent patient exposure to FluMist or other attenuated influenza vaccines may cause inaccurate false negative RSV results.
Interference was observed for flu A, flu B, RSV, and SARS-CoV-2 when evaluated with high concentrations of Pneumocystis jirovecii (PJP). There is a risk of false negative for flu A, B, RSV, and SARS-CoV-2 results under certain co-infection circumstances with Pneumocystis jirovecii (PJP).
The Alinity m Resp-4-Plex assay was validated with nasopharyngeal swabs. Anterior nasal swabs (self-collected under healthcare provider (HCP) supervision or HCP-collected) are also considered acceptable specimen types, but performance has not been established. The analytical performance of mid-turbinate specimens was validated by the Microbiology Laboratory.
The test will be performed multiple times per day with results reported within 48 hours of receipt of specimen in the laboratory contingent upon testing capacity.
MLabs has limited supplies of NP swabs and transport media. Please contact client services at 800-862-7284 to determine availability of supplies for your testing needs. MLabs can accept testing from clients that provide their own collection supplies.
Nasopharyngeal specimen collection:
With the head in a tilted position, insert the swab into one nostril, advancing into the nasopharynx until resistance is felt. Rotate the swab several times on the nasopharyngeal membrane to allow adequate collection of epithelial cells - a minimum of 3 "full twists" is standard to obtain a good collection; if unsure you maintained contact with the membrane, add another 1-2 full twists.
Insert swab into viral transport media or phosphate buffered saline. Break off swab stick at the breakpoint to ensure it will fully fit into the closed tube. Fasten the cap tightly to prevent leakage. Refrigerate.
Send to the laboratory as soon as possible. Obtaining columnar epithelial cells will enhance reliability of viral detection.
Anterior nasal specimen collection (performed by a healthcare provider or the patient after reviewing and following the collection instructions):
Insert the entire collection tip of the swab provided (usually ½ to ¾ of an inch, or 1 to 1.5 cm) inside the nostril. Firmly sample the nasal wall by rotating the swab in a circular path against the nasal wall at least 4 times. Take approximately 15 seconds to collect the specimen. Be sure to collect any nasal drainage that may be present on the swab. Repeat in the other nostril using the same swab. Place swab, tip first, into the transport tube provided.
Mid-turbinate specimen collection:
Use a tapered swab. Tilt patient’s head back 70 degrees. While gently rotating the swab, insert swab less than one inch (about 2 cm) into nostril parallel to the palate (not upwards) until resistance is met at turbinates. Rotate the swab several times against nasal wall and repeat in other nostril using the same swab.Place swab, tip first, into the transport tube provided.
Please see CDC for current sample collection guidance: https://www.cdc.gov/coronavirus/2019-nCoV/lab/guidelines-clinical-speci…
Please refer to Michigan Medicine COVID testing guidelines for recommended specimen type based on test indication:
Please see CDC for current sample collection guidance: https://www.cdc.gov/coronavirus/2019-nCoV/lab/guidelines-clinical-specimens.html
Laboratories within the United States and its territories are required to report all SARS-CoV-2 results to the appropriate public health authorities.
Additional information from the CDC can be found below:
• COVID-19: https://www.cdc.gov/coronavirus/2019-ncov/index.html
Additional information about the interpretation and use of the Abbott Alinity m Resp-4-plex assay can be found within the following fact sheets:
Health Care Providers: https://www.fda.gov/media/146489/download