Differential Diagnosis for a 43-year-old Woman with Bilateral Apical Cavitary Lesions and Hilar Lymphadenopathy

Single Most Likely Diagnosis

• Histoplasmosis: Given the patient's symptoms of bilateral apical cavitary lesions with hilar lymphadenopathy and a productive cough, histoplasmosis is a strong consideration, especially if she has a history of travel to an undeveloped country or exposure to bird or bat droppings. This fungal infection is common in endemic areas and can present with these radiographic findings.

Other Likely Diagnoses

• Tuberculosis (TB): TB is a significant consideration given the radiographic findings of bilateral apical cavitary lesions and hilar lymphadenopathy. A history of travel to an undeveloped country increases the likelihood of exposure to TB. Chronic cough and productive sputum also align with TB.
• Sarcoidosis: This condition, which can be associated with connective tissue disorders, often presents with hilar lymphadenopathy and can have pulmonary infiltrates, including cavitary lesions in advanced cases. It's less likely to cause productive cough but is a consideration given the lymphadenopathy.
• Chronic Cavitary Pulmonary Aspergillosis: In individuals with a history of chronic lung disease or immunocompromised states, aspergillosis can cause cavitary lesions. However, it's less commonly associated with hilar lymphadenopathy.

Do Not Miss Diagnoses

• Lung Cancer with Metastatic Disease: Although less likely given the bilateral apical distribution and presence of lymphadenopathy, lung cancer (especially if the patient has a history of chronic tobacco use) can present with cavitary lesions and should not be missed due to its significant implications.
• Wegener's Granulomatosis (Granulomatosis with Polyangiitis, GPA): This is a vasculitic condition that can present with cavitary lung lesions, renal disease, and often has a significant respiratory symptomatology. It's crucial not to miss this diagnosis due to its potential for severe morbidity and mortality if untreated.

Rare Diagnoses

• Cryptococcosis: This fungal infection can cause pulmonary lesions, including cavitation, especially in immunocompromised patients. It's less common than histoplasmosis or TB but should be considered in the appropriate clinical context.
• Coccidioidomycosis: Another fungal infection that can cause cavitary lung lesions, typically in individuals who have traveled to or live in the southwestern United States. It's less likely given the lack of specific geographic mention but remains a consideration with travel to endemic areas.

Each of these diagnoses has a different set of implications for treatment and prognosis, highlighting the importance of a thorough diagnostic workup to determine the underlying cause of the patient's symptoms.