A 66-year-old man comes to the emergency department due to increasing shortness of breath over the past 5 days. He has had a nonproductive cough for 4 days. The patient appears ill. Neck veins are nondistended. There is decreased chest expansion on the right side. Auscultation reveals decreased breath sounds over the right lung base and dullness to percussion. Chest imaging shows a right lower lobe infiltrate and a mild pleural effusion on the right side. Thoracentesis is performed. Pleural fluid and serum findings are as follows: Which of the following is contributing most to the pathogenesis of this patient's pleural effusion?

Question

A 66-year-old man comes to the emergency department due to increasing shortness of breath over the past 5 days.  He has had a nonproductive cough for 4 days.  The patient appears ill.  Neck veins are nondistended.  There is decreased chest expansion on the right side.  Auscultation reveals decreased breath sounds over the right lung base and dullness to percussion.  Chest imaging shows a right lower lobe infiltrate and a mild pleural effusion on the right side.  Thoracentesis is performed. Pleural fluid and serum findings are as follows:  Which of the following is contributing most to the pathogenesis of this patient's pleural effusion?

Quizplus · Accepted Answer

Eductional Objective: Transudative effusions are typically caused by alterations in hydrostatic or oncotic pressure (eg, heart failure, cirrhosis, nephrotic syndrome), whereas exudative effusions typically result from inflammation and consequent increased vascular membrane permeability (eg, infection, malignancy, rheumatologic disease).  Exudative effusions are characterized by a high ratio of pleural fluid to serum total protein (>0.5) or lactate dehydrogenase (>0.6), or high absolute levels of lactate dehydrogenase.

A 66-Year-Old Man Comes to the Emergency Department Due to Increasing