Question

A positive PPD indicates:

A. Exposure to Mycobacterium tuberculosis
B. Active tuberculosis infection
C. Dormant tuberculosis infection
D. Vaccination with BCG
E. Any of the above is possible

Answer 1

The interpretation of PPD test result is an important step in deciding if the person is actually tested positive or not. Generally, the size of induration on the person’s skin and their medical risk factors are taking in the consideration together while interpreting the PPD test result. A person can have induration on skin of the test arm and can be tested positive for PPD if they have been exposed to Mycobacterium tuberculosis, have active or dormant tuberculosis infection, have been vaccinated for BCG, or in many other different scenarios. Therefore, you should select the option ( E) i.e. Any of the above is possible.

Thanks!