Sarcoidosis: This is the most common cause of bilateral hilar lymphadenopathy, characterized by the formation of granulomas in various organs, including the lungs and lymph nodes. It often presents with symmetric bilateral hilar adenopathy on chest radiographs.

Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma can cause bilateral hilar lymphadenopathy. The presence of systemic symptoms such as fever, night sweats, and weight loss may suggest this diagnosis.
Tuberculosis: Although more commonly associated with unilateral lymphadenopathy, tuberculosis can cause bilateral hilar lymphadenopathy, especially in immunocompromised patients or in certain forms like miliary tuberculosis.
Histoplasmosis: This fungal infection can cause lymphadenopathy, particularly in endemic areas. It may present with bilateral hilar adenopathy, especially if the infection is acute.

Lymphangitic Carcinomatosis: Metastatic cancer to the lungs can cause lymphadenopathy, and certain types like breast, lung, and stomach cancer are more prone to spread to the lymph nodes. Missing this diagnosis could lead to delayed treatment of an underlying malignancy.
Wegener's Granulomatosis: Now known as Granulomatosis with Polyangiitis (GPA), this is a form of vasculitis that can affect the lungs and cause lymphadenopathy. It's crucial to diagnose and treat promptly to prevent organ damage.

Castleman Disease: A rare disorder that involves an overgrowth of cells in the lymph nodes, which can cause lymphadenopathy. It can be unicentric (localized) or multicentric (systemic).
Kimura Disease: A rare, chronic inflammatory disorder that can cause lymphadenopathy, typically in the head and neck region, but can occasionally involve the hilar lymph nodes.
Silicosis: A form of occupational lung disease caused by the inhalation of silica particles, which can lead to lymphadenopathy among other pulmonary manifestations. It's rare in the general population but should be considered in individuals with a relevant occupational history.