DISCUSSION
Differential diagnosis
Granulomatosis with polyangiitis. GPA, also known as Wegener granulomatosis, is characterized by necrotizing granulomatous inflammation with necrotizing vasculitis, usually of small and medium vessels; ocular involvement is frequent.1 Ocular granulomas of GPA can be mistaken for those caused by other diseases, such as mycobacterial or syphilitic infection or idiopathic uveitis.2
Tuberculosis. Common symptoms of TB include fever, cough, dyspnea, weight loss, malaise, and fatigue. Granulomas are typically necrotizing but are occasionally nonnecrotizing.3 TB can manifest with hilar and diffuse lymphadenopathy,4 which the patient’s chest imaging revealed (see Figure 1). Granulomas produced by Mycobacterium tuberculosis and atypical mycobacteria are similar histopathologically to sarcoidosis granulomas, complicating the diagnostic process.5
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