Dear friend, welcome and thanks for entrusting your query here at HCM!
I am Dr. Prasad Akole (Critical Care Expert- http://bit.ly/Dr-Prasad-Akole) and am glad to address to your query here.
The skin tests for TB are indicative and have many false positives and negatives.
Confirmation of TB is only on demonstrating TB bacilli or caseating necrosis
or culture of the germs.
Yes, anti-tubercular therapy is hepato-toxic and may cause liver damage
So treatment should be started only on confirmation or it is a strong clinical suspicion of the doctor and risk benefit ratio is favourable to treat.
Please be guided by your physician and need to look for more evidence of TB infection by further testing.
I hope you are fully satisfied with the guidance I gave.
I would be glad to answer any further queries. May I request you to rate your experience here before you close.
Thank you and Good luck!