All of the following are confirmatory tests for H2N2 except?

MP CHO - 2022

Microbiology

Easy

Appeared in: MP CHO - 2022

Explanation

C-reactive protein (CRP) is a non-specific marker of inflammation found in the blood.
Its levels increase in response to a wide variety of conditions, including infections (both bacterial and viral), autoimmune diseases, and tissue injury.
Because it is not specific to any single pathogen, it cannot be used to confirm an infection with a particular virus like H2N2 influenza.

Option A: Real-time PCR (RT-PCR) is a primary and highly sensitive molecular method used to confirm influenza infection by detecting the virus's specific genetic material (RNA).
Option B: Viral culture is a gold-standard confirmatory test that involves isolating and growing the live virus from a patient sample, allowing for definitive identification.
Option C: Detecting a four-fold rise in virus-specific neutralizing antibodies between acute and convalescent serum samples is a standard method for retrospectively confirming a recent infection.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Diagnostic and confirmatory tests for influenza (H2N2) as background academic context rather than a clinical decision trigger.
Nurses play a critical role in collecting appropriate respiratory samples (e.g., nasopharyngeal swabs) at the right time to ensure the accuracy of diagnostic tests like PCR and viral culture.
Understanding the difference between confirmatory and non-specific tests helps nurses interpret lab results in the context of a patient's clinical presentation and advocate for appropriate treatment and infection control measures.
What if? If a patient with suspected influenza has a negative rapid antigen test but is at high risk for complications, the nurse should anticipate that the provider may still start antiviral treatment empirically and order a more sensitive confirmatory test like RT-PCR.

How to Approach the Question

First, identify the keywords in the question stem. The key terms here are "confirmatory tests," "H2N2," and the negative word "except."
The word "except" means you are looking for the option that does NOT fit the category of a confirmatory test for H2N2.
Evaluate each option individually to determine if it is a valid confirmatory test for influenza.
Option A (Real-time PCR), Option B (Viral culture), and Option C (Virus-specific neutralizing antibodies) are all established methods for confirming a viral infection.
Option D (CRP) is a general marker of inflammation and does not confirm a specific virus. Therefore, it is the exception.
Select the option that is the outlier or does not belong with the others in the context of the question.

Concept Tested & Keywords

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