The course of tuberculosis
is from 6-9 months.
It will take some time to get response clinically.
Actually sputum examination should be done to confirm TB.
Serological tests should not be done in India for TB.
will come positive even after BCG vaccination
If FNAC is negative and is done by a good pathologist, i have doubt regarding the diagnosis of TB.
Lymphnode enlargement can be due to simple bacterial infection
Please consult a Chest physician and Surgeon for correct diagnosis and proceed.