A 53-year-old man develops weakness, malaise, cough with bloody sputum and night sweats. A chest X-ray reveals numerous apical densities bilaterally, some of which are cavitary. Exposure to Mycobacterium tuberculosis was documented 20 years ago, and M. tuberculosis is identified in his sputum. Which of the following describes the expected lung pathology in this patient?
High-Yield Explanation
Secondary (reactivation) tuberculosis occurs due to: Reactivation Fresh infection Secondary TB: characterized by the formation of granulomas and extensive tissue destruction (caseous necrosis). Mycobacteria typically spread to the apices of the lungs and produce large cavities, which are associated with hemoptysis. Apical lesion: Supraclavicular- Puhl's focus Infraclavicular- Assmann's focus Hilar LN- not affected. Miliary tuberculosis refers to widespread seeding of bacteria in the lungs and distant organs. Granulomatous inflammation may induce fibrosis as a secondary feature.