Would a tb test do any harm to an anorexic person? does it harm a person who has a loss of nutrition. what happens when it is taken?

No harm: Tb test in an anorexic person who has significantly poor nutrition does not cause harm. But it can sometimes be falsely negative as severe nutritional deprivation is associated with poor immune response, thereby blunting normal immune response to TB test. Once the person recovers, the TB test may give a more accurate result. It depends on your individual risk factors for urgency of testing.