A 66-year-old man with a history of alcoholism and poor dentition presents with 1 week of fever, dyspnea, and cough productive of purulent sputum. Chest radiographs reveal infiltrates in the posterior segments of the upper lobes. If untreated, what is the most likely complication of this disease

The most likely complication of this disease is the development of Empyema.

Explanation:

The patient has symptoms of fever, dyspenea (breathlessness with chest pain), cough and sputum which directs towards empyema as they are symptoms of pneumonia and prolonged symptoms would cause empyema.

The infiltrates in the posterior segments of upper lobe of the right lung results in bulging fissure causing necrosis lesion which would cause the complications of empyema.

The empyema is the condition in which pus cells are formed in thoracic cavity, in pleural fluid bacterial infection occurs due to pneumonia or surgery of chest.

The empyema risk is high for diabetics, pulmunary infected and alcoholism.