A nurse is caring for a client with suspected tuberculosis (TB) who has provided sputum samples for testing. Which laboratory test is used to confirm the presence of Mycobacterium tuberculosis in sputum samples?

A) Incorrect. Chest X-rays are often used to assess lung involvement in TB but are not a primary screening test for TB infection.

B) Incorrect. Sputum culture is used to confirm the presence of TB bacteria in individuals with suspected active TB disease.

C) Correct. The Mantoux TST is a common screening test for TB infection. A small amount of PPD is injected under the skin, and the reaction is assessed after 48-72 hours.

D) Incorrect. CT scans may be used in TB diagnosis but are not typically used for initial screening of TB infection.

A) Correct. Sputum samples are often most concentrated with TB bacteria when collected in the morning, as they have had time to accumulate overnight.

B) Incorrect. Rinsing the mouth before collecting sputum may dilute the sample and reduce its accuracy.

C) Incorrect. Deep coughing is encouraged to obtain samples from the lower respiratory tract, where TB bacteria are more likely to be present.

D) Incorrect. Sputum samples should be collected in specific containers designed for this purpose to maintain sample integrity and avoid contamination.