Thanks for your query at HCM! According to me either your wife is undertreated which caused relapse or she is a case of Multi-drug resistant TB/ Extensively drug resistant TB. I suggest get the ZN smear & culture and sensitivity done for Mycobacterium TB by BacT/Alert. Also get the Hains test done to detect resistant to first line or second line TB drugs. Also it can help to identify if she is suffering fro a rare type of TB called Non-tuberculous Mycobacteria (NTM) which requires absolutely different treatment. Let her treatment be guided by evidence based medicine. I am sure she will respond. Visit a pulmonologist/ ID physician for correct dosage of drugs. She will require prolonged treatment based on sensitivity results. Take care.