A client has a positive tuberculosis (TB) skin test and a negative chest x-ray. What could explain this situation?

A positive tuberculosis skin test indicates that a person has been exposed to the bacteria that cause TB, leading to an immune response. However, the presence of a negative chest x-ray suggests that there is no active pulmonary TB infection or any significant lung disease.

In this context, the most plausible explanation is that the client had a previous TB infection or received the Bacillus Calmette-Guérin (BCG) vaccine, which is used in some countries to prevent TB. Previous infection can lead to a positive skin test result due to the immune system's memory of the bacteria, even if the infection is no longer active. Similarly, the BCG vaccine can also cause a positive skin test result without indicating an actual infection with active disease.

The provided rationale emphasizes the distinction between a historical infection or vaccination and the current state of health, which is reflected in the negative chest x-ray. Understanding this connection is vital in managing potential TB cases and interpreting skin test results accurately.