Understanding the MT (Mantoux) Test for Tuberculosis

Study Notes

Also known as the Mantoux test, it is a diagnostic tool used to determine if someone has been infected with tuberculosis (TB)
Not a perfect test, but it is widely used due to its simplicity and relatively low cost

A small amount of a substance called tuberculin is injected just beneath the skin of the forearm
The tuberculin is a purified protein derivative (PPD) of the TB bacterium
The test is read 48-72 hours later by a healthcare professional
A positive reaction indicates that the person's immune system has reacted to the PPD, suggesting previous exposure to TB

A positive result is indicated by a raised, hard bump (induration) at the injection site
The size of the induration is measured in millimeters
A reaction of 5mm or more is considered positive for people with HIV/AIDS, organ transplants, or those taking immunosuppressive therapy
A reaction of 10mm or more is considered positive for people with a high risk of TB exposure, such as healthcare workers
A reaction of 15mm or more is considered positive for people with a low risk of TB exposure

Known as the Mantoux test, utilized to diagnose tuberculosis (TB) infection.
Valued for its simplicity and cost-effectiveness, despite not being a definitive test.

A small tuberculin amount, a purified protein derivative (PPD) of the TB bacterium, is injected subcutaneously in the forearm.
Test results are assessed by a healthcare professional after 48-72 hours.
A positive test reveals an immune response to PPD, indicating prior TB exposure.

A positive reaction is identified by a raised, hard bump (induration) at the injection site.
Induration size is quantified in millimeters.
5mm or more: positive for individuals with HIV/AIDS, organ transplant recipients, or those on immunosuppressive therapy.
10mm or more: positive for high-risk populations, including healthcare workers.
15mm or more: positive for individuals at low risk for TB exposure.