Best Answer:  They often died of blood loss ... the infection eroded a blood vessel and they bled to death, which could be spectacularly messy and gory if your plot needs it with blood pouring out of their mouth and nose OR or just a sudden fit of coughing and falling over dead with an internal bleeding.

Another way, less spectacular, was slow suffocation as the lungs became filled with the "tubercules"and the person slowly breathed less and less well and then died. The lack of oxygen was stressful to the heart, and it would just stop.