Paradoxical reactions in non-HIV tuberculosis presenting as endobronchial obstruction.

Paradoxical reaction (PR) in tuberculosis (TB) is common and may affect up to 25% of patients. PR has the potential to cause significant morbidity and, on occasion, death. Although PR has been recognised for some time, the pathophysiology, especially in HIV-negative patients, is not well understood. We present two cases of PR in HIV-negative patients with TB presenting as significant airway obstruction secondary to a florid endobronchial component. These cases demonstrate that PR should be considered in all patients presenting with airway symptoms who have started TB treatment. The outcomes of the cases illustrate the need for wider recognition of this condition and more research to characterise patients who may be at risk, in order to gain a greater understanding of the mechanisms involved and to make or predict this diagnosis earlier.