20 years ago, after my first year working in a hospital (medical records) my TB skin test turned positive. After waiting 2 weeks, they did another skin test which was also positive. I was put on INH therapy for 6 months. After 3 months, I started having nerve problems in my hands and feet. Stabbing needle pains. They did nerve conduction studies that showed I developed Stage II nerve damage (stage III is irreversible, stage II "can" reverse itself) I was taken off INH after 4 months. I still have nerve problems in my hands and feet plus restless leg syndrome and a wandering neuropathy. Now 20 years later, I started a new job at a new hospital. After telling the health screen nurse all this, she said there is a blood test that can determine if you "really" have been exposed or if you are just allergic to a component of the skin test or if the skin test was actually read properly. After listening to her explain how the skin test should read on an actual positive, I knew my test 20 years ago was not read properly. A "real" positive should have an M&M size nodule underneath the skin that is very very hard. The nodule does not go away for a few weeks. The nodule and any redness around the area should be measured accurately for that is a determining factor also. This health screen nurse offered to do a blood test and I'm sorry I forget the name of the test but it has "gold" in the name. Sure enough, it turns out I was never exposed to TB AT ALL. I didn't have to take INH. I didn't have to go through 20 years of restless leg syndrome, needle pains in my feet or hands, or wandering neuropathy! I didn't have to worry and fret if I was going to develop TB and expose my family to it. I will have restless leg syndrome the rest of my life (I'm 48) Its painful!
Please, if you have had a positive skin test, find a hospital that will do this blood test. It is a very expensive test (approx $375) but completely worth it. If you don't have to take INH, don't!! Its a damaging drug. It has impacted my life for the rest of my life... all for nothing. Please take the blood test to make absolutley sure you were exposed to TB.