Confirmative test for diagnosis of tuberculosis is - - RUHS, Jaipur, PB B.Sc Nursing Entrance-2023

RUHS, Jaipur, PB B.Sc Nursing Entrance-2023

Medical & Surgical Nursing

Easy

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2023

Explanation

Sputum culture is the gold standard and most definitive test for confirming active pulmonary tuberculosis.
It provides direct evidence by isolating and growing the causative agent, Mycobacterium tuberculosis, from a patient's sputum.
A positive culture confirms active infection and is essential for performing Drug Susceptibility Testing (DST) to guide appropriate treatment.

Option A: Bronchoscopy is an invasive procedure used to collect samples (like bronchoalveolar lavage) from the lungs. It is a method of sample collection, not the diagnostic test itself.
Option C: The Tuberculin (Mantoux) test is a screening tool that detects an immune response to TB antigens. It cannot differentiate between a past/latent infection and an active disease state.
Option D: The Erythrocyte Sedimentation Rate (ESR) is a non-specific blood test that indicates the presence of inflammation somewhere in the body. It is not specific to tuberculosis.

Clinical Relevance

Nursing practice connection: Use the key finding related to Confirmatory diagnostic tests for Tuberculosis to guide bedside assessment, documentation, and the next nursing action.
A definitive diagnosis via culture is crucial before initiating the long course of anti-tubercular therapy (ATT) to ensure correct treatment and prevent the development of drug resistance.
Culture allows for Drug Susceptibility Testing (DST), which is vital for identifying drug-resistant strains like MDR-TB and guiding the selection of an effective treatment regimen.
What if? If a patient is critically ill and TB is strongly suspected, treatment may be started based on strong clinical evidence and results from faster tests like smear microscopy or molecular tests (e.g., CBNAAT), while waiting for the culture results for confirmation and DST.

How to Approach the Question

First, identify the key term in the question: 'Confirmative test'. This asks for the test that provides definitive proof of the disease, not just a suggestion.
Next, evaluate each option based on its role in the diagnostic process.
Recall the difference between screening tests (suggest possibility), supportive tests (add evidence), and confirmatory tests (prove diagnosis).
Sputum culture directly isolates and identifies the living pathogen, making it the definitive confirmation.
The Tuberculin test only screens for immune response/exposure. ESR is a non-specific inflammation marker. Bronchoscopy is a procedure to obtain a sample, not the test itself.
By eliminating the non-confirmatory options, you can confidently select the correct answer.

Concept Tested & Keywords

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