###Human: Can latent TB scaring be misdiagnosed as interstitial lung disease with RA? ###Assistant: Hello. I can understand your concern. According to your statement, you have been suffering from chronic bronchitis with rheumatoid arthritis with recently diagnosed with RA related interstitial lung disease or idiopathic pulmonary fibrosis. You had a history of PTB and taking anti-tubercular drugs. You are concerned about your recent diagnosis based on HRCT chest whether it is RA-ILD/IPF or latent TB related complications for your past sufferings and now you feel a lot better. Your HRCT of chest reveals (attachment removed to protect patient identity), interstitial fibrosis characterized by peripheral traction bronchiectasis, irregular reticulation in all lobes, microtubules with calcification in mid and lower lungs, lower lobe predominant microcystic changes without significant ground glass opacifications, hilar calcified lymph nodes consistent with chronic granulomatous disease, and bronchial wall thickening bilaterally. Similar type of radiological findings can be found in post TB fibrosis, chronic obstructive pulmonary disease which includes two key components chronic bronchitis and emphysema, RA-ILD or IPF, etc. You may not tell your doctor about your previous history of Latent TB. For that reason his diagnosis was RA-ILD or IPF as you are suffering from RA. So he was not wrong as your radiological reports suggest the above mentioned differential diagnosis. Again, on high altitude, your doctor found crackles as you are suffering from COPD and it may be associated with infections that time and now it not heard as your infection was subsided.