Reactivation of Tuberculosis in the Setting of COVID-19 Infection.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2) was declared a pandemic by WHO in March 2020. The causative organism has since undergone a series of mutations. COVID-19 primarily being a respiratory illness causes pre-existing pulmonary diseases to show worse clinical outcomes. About one-third of the world's population is thought to be infected with latent Mycobacterium tuberculosis (MTB). Both previous and newly developed tuberculosis (TB) infection are risk factors for COVID-19 and are associated with poor outcomes. T lymphocytes play a pivotal role in defense against MTB and with evidence suggesting depletion of T lymphocytes in COVID-19, it can be postulated that COVID-19 can increase the risk of reactivation of latent TB.  Given that a large population around the globe is infected with latent tuberculosis, it is interesting to study and note cases where the virus leads to the reactivation of latent tuberculosis infection. Herein, we present a 76-year-old Brazilian male recently treated for COVID-19 pneumonia, presenting with new-onset cough and weakness diagnosed with latent MTB reactivation.