Name of the Procedure:

Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, for multiple types or sub-types, includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, first 2 types or sub-types. Common names: Influenza PCR test, Flu multiplex assay.

Summary

This procedure involves using advanced molecular techniques to detect the presence of influenza viruses in a patient's sample. It identifies multiple types and sub-types of the flu virus by examining their genetic material (RNA or DNA).

Purpose

The procedure is used to identify the type and subtype of influenza virus causing an infection. This helps in diagnosing flu and can guide the selection of the appropriate antiviral treatment. It also assists in monitoring the spread and evolution of flu viruses in the population.

Indications

• Fever, cough, and body aches
• Influenza-like symptoms, especially during flu season
• Severe respiratory illness requiring hospitalization
• Cases where rapid diagnostic tests have given uncertain results

Preparation

• No specific preparation is generally required.
• Patients may be asked to avoid certain nasal sprays or treatments before sample collection.
• Diagnostic tests such as a rapid flu test may be performed prior to this procedure for preliminary screening.

Procedure Description

1. A sample, usually a nasal or throat swab, is collected from the patient.
2. The sample is processed in a laboratory where viral RNA is extracted.
3. Reverse transcription converts the RNA to complementary DNA (cDNA).
4. Multiplex PCR is then used to amplify the cDNA, targeting specific sequences unique to different flu virus types and sub-types.
5. Probes labeled with fluorescent markers bind to the amplified DNA, allowing the lab to detect and identify the specific influenza viruses present.

Duration

The laboratory portion of the procedure typically takes a few hours to complete. Results are usually available within 24-48 hours.

Setting

The sample collection can be done in any medical setting such as a hospital, outpatient clinic, or doctor’s office. The analysis is performed in a specialized laboratory.

Personnel

• Healthcare professionals involved in sample collection: Nurses or physician assistants.
• Laboratory personnel: Medical laboratory scientists or technologists.

Risks and Complications

• Common: Mild discomfort during sample collection.
• Rare: Minor nosebleed or irritation from nasal swab.
• There are minimal risks as this is a non-invasive diagnostic test.

Benefits

• Accurate identification of influenza virus type and subtype.
• Helps in selecting the most effective antiviral treatment.
• Aids in public health surveillance and preventing the spread of flu.

Recovery

• No recovery time required as it is a diagnostic test.
• Patients can resume normal activities immediately after sample collection.
• Follow-up may depend on the results and the treatment plan prescribed by the healthcare provider.

Alternatives

• Rapid influenza diagnostic tests (RIDTs): Quicker but less sensitive.
• Viral culture: More accurate but takes longer to yield results.
• Serological tests: Used less frequently and mainly for research purposes.

Patient Experience

During sample collection, patients may experience brief discomfort or a tickling sensation in the nose. After the procedure, there are no lingering effects, and pain management is generally unnecessary.