A Unique Case of COVID Pneumonia, Tuberculosis, and Silicosis

A 72-year-old man presented to our emergency room for evaluation of fevers, chills, and myalgias for twelve weeks. He also reported a history of chronic productive cough and chest tightness. Two weeks prior to presentation, he was working at the local international airport in March of 2020 when he noticed increasing dyspnea with exertion whilst performing routine tasks at his job. At the time of our interview, he denied sick contacts and no known history of tuberculosis exposure. He also reported a remote history of working as a stone cutter in concrete mines in Honduras. A chest x-ray was performed and demonstrated bilateral mass-like upper lobe opacities that were present on imaging two years prior. Computed tomography of the chest (figure 1) revealed volume loss and mass-like perihilar upper lobe predominant opacities with fibro-retractile architectural distortion, peribronchovascular and centrilobular nodules, and scattered areas of patchy ground-glass opacification with bibasilar predominance. His fibrotic changes were thought to be consistent with silicosis with progressive massive fibrosis secondary to prior inorganic dust inhalation. A superimposed process underpinning his acute presentation was suspected given the findings of patchy ground-glass opacities. A SARS-CoV-2 PCR test was obtained and was positive. Given several months of symptoms preceding this acute presentation, a third process was suspected, especially in light of his immigration history and centrilobular nodular pattern on imaging. An interferon gamma release assay for tuberculosis, mycobacterium tuberculosis PCR and mycobacterial cultures from expectorated sputum were obtained, all with positive results. He was discharged with a standard regimen of Rifampin, Isoniazid, Pyrazinamide, and Ethambutol with follow-up with the health department at which point he had recovered from his acute illness. He did remarkably well in regards to his COVID-19 diagnosis. He did not receive any COVID specific therapies given his active diagnosis of TB and was discharged home on room air. Silicosis is a well-known predisposing factor to development of tuberculosis, thought to arise from silica particulate macrophage dysfunction. A combination of immune dysfunction related to silicosis and occupational exposure likely led to development of viral pneumonia in this patient. His occupation at a large international airport in March 2020 prior to the institution of quarantine and travel restrictions uniquely put him at risk for both TB and COVID-19 pneumonia, which is nicely demonstrated with these classic CT findings.