Mantoux test is one of the diagnostic tests for?

Appeared in: MNS 2015

Explanation

The Mantoux test, also known as the Tuberculin Skin Test (TST), is a standard method to screen for infection with Mycobacterium tuberculosis.
It works by detecting a delayed-type hypersensitivity immune response to Purified Protein Derivative (PPD), an antigen derived from the bacteria.
The test involves an intradermal injection of PPD into the forearm, with the result read 48-72 hours later.
A positive reaction, indicated by a measured area of induration (not just redness), suggests a past or present infection with the TB bacteria.

Option A: Diphtheria is a bacterial infection diagnosed primarily through clinical presentation (e.g., a thick gray membrane covering the throat) and confirmed with a throat swab culture.
Option C: Tetanus diagnosis is based entirely on clinical signs and symptoms, such as lockjaw (trismus), muscle stiffness, and spasms. There is no diagnostic laboratory or skin test for tetanus.
Option D: Leprosy (Hansen's disease) is diagnosed by identifying acid-fast bacilli in samples from skin lesions (slit-skin smears) or through a skin biopsy.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Mantoux test for Tuberculosis diagnosis as background academic context rather than a clinical decision trigger.
Nurses are responsible for correctly administering the Mantoux test using the intradermal technique, ensuring a wheal is formed.
Accurate reading of the test at 48-72 hours is a critical nursing skill. The measurement of the induration (not redness) in millimeters must be documented precisely.
Interpretation is context-dependent; a 5 mm induration can be positive in an HIV-positive patient but negative in a healthy individual with no risk factors. Nurses must be aware of these risk categories.

How to Approach the Question

This is a factual recall question that tests your knowledge of specific diagnostic procedures.
First, identify the key term in the question stem: 'Mantoux test'.
Access your knowledge base about common diagnostic tests. The Mantoux test is one of the most well-known skin tests in medicine.
Associate the Mantoux test with its primary target disease, which is Tuberculosis.
Review the options to confirm your answer and mentally eliminate the incorrect choices by recalling their respective diagnostic methods (e.g., Diphtheria - culture, Tetanus - clinical signs).

Concept Tested & Keywords

QFcwuqctv2444C17TgNcz4

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart B (pp 202-403 of 604) p. 25-27

E6 Ghai Essential Pediatrics(pp 26-904 of 913) p. 257-259

Practise the full MNS 2015

Attempt every question from this paper in a timed mock, then review the full solution for each one.