55 year old female , reported after 1 year of ATT with non responsive cough and worsening exertional dyspnoea. She was sputum smear negative and her TT was also negative.She had no weight loss . What is the likely diagnosis ? How will you confirm it ?

Evolving lung fibrosis in a perihilar and paralymphatic distribution.Sarcoidosis is likely.Endobronchial biospsies ,BAL or TBLB should establish the diagnosis.