How bronchopleural fistula develops in secondary TB?

how bronchopleural fistula develops in secondary TB?

The pathophysiology of the subacute and chronic forms of bronchopleural fistulae (BPF) are primarily related to infection and are often seen in immunocompromised or debilitated patients with multiple comorbidities. The chronic form is associated with an infectious process and fibrosis of the pleural space. Thank you.