A patient with low-grade fever and weight loss has poor excursion on the right side of the chest with decreased fremitus, dullness to percussion, and decreased breath sounds all on the right. The trachea is deviated to the left. The most likely diagnosis is

The diagnosis in this patient is suggested by the physical exam findings. The findings of poor excursion, flatness of percussion, and decreased fremitus on the right side are all consistent with a right-sided pleural effusion. A large right-sided effusion may shift the trachea to the left. A pneumothorax should result in hyperresonance of the affected side. Atelectasis on the right side would shift the trachea to the right. A consolidated pneumonia would characteristically result in increased fremitus, flatness to percussion, and bronchial breath sounds, and would not cause tracheal deviation.