Introduction While Post Tuberculous (TB) Bronchiectasis is the most common cause of Bronchiectasis in South Asia, there has been little research into its microbiology and clinical characteristics in Pakistan. This single centre retrospective cohort study at Bach Christian Hospital (BCH) in rural Northern Pakistan seeks to address this issue. Methods Demographic, Imaging, Aetiological and Microbiological data were obtained from 32 patients with Bronchiectasis at BCH from between January 2023 and December 2023. Results 76% (25/32) of all cases of Bronchiectasis were Post TB. TB infection was seen in 5 cases of Post TB Bronchiectasis, TB with bacterial or fungal co infections in 4, and single bacterial infections in 4. In post TB Bronchiectasis 4 patients had growth of a single bacterium. Drug sensitivities were obtained for bacterial isolates. One patient each with Post TB and Non-TB Bronchiectasis died from Type 2 Respiratory failure despite appropriate treatment. 2 patients with Post TB Bronchiectasis and destroyed lung syndrome improved but with ongoing significant respiratory impairment. All other patients improved with treatment. Discussion 1. The frequency of Post TB Bronchiectasis is very high even for South Asia. 2. A significant number (8/24) of Post TB Bronchiectasis had re-infection or failure to improve despite appropriate drug treatment. TB PCR (Polymerase Chain Reaction) on Bronchoalveolar lavage (BAL) was key in the management of these patients. 3. Among patients with Post TB Bronchiectasis, those with co-infection present a difficult treatment challenge. 4. Some patients with Post TB Bronchiectasis have significant complications such as destroyed lung syndrome which is difficult to manage. 5. Drug susceptible bacteria and NTM were less commonly isolated than in other studies. Conclusion Further research is needed particularly to manage Post TB Bronchiectasis patients with co-infections or complications such as significant structural lung disease.

The authors have declared no competing interest.

This study did not receive any funding.

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Bach Christian Hospital Ethics Committee gave ethical approval for this work

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