Hi, i am 30 years old and since 2005 i have this unusualities in my right upper lung. I did not mind this because everytime i do pre-employment medical examination which includes CXR, I always get medically fit advice. Now that i am flying to USA as a worker (seafarer to be exact), i am advised to start on anti PTB drugs and be back to the clinic after two months (this coming June 30). I am just wondering what seem to be the problem. I have read about latent TB infection. Could i possibly have that? I was never sick, no symptoms or whatsoever, my sputum smear came out negative. Pls help me, I want to get clearance, but i am not sure if my dream of going to USA ends here because of this scar. I have old xray films to show that the fibrous density found in my lung has no activity for the past 9 years.

Summarized question: What causes Pulmonary tuberculosis?