Hypothyroidism-Related Pleural Effusion

Pathophysiology and Presentation

• Severe, long-standing hypothyroidism can lead to fluid accumulation in various body cavities, including the pleural space, due to increased capillary permeability and other mechanisms 1, 2

Diagnostic Considerations

• The American Heart Association, as published in Circulation, suggests that hypothyroidism should be considered in the differential diagnosis of unexplained pleural effusions, especially when accompanied by other signs of hypothyroidism 3
• The European Society of Cardiology recommends that thyroid function tests (TSH, T4) should be performed in patients with unexplained pleural effusions, as suggested in the European Heart Journal 1, 3

Clinical Pearls and Pitfalls

• The American College of Cardiology, as published in Circulation, notes that the presence of hypothyroidism does not exclude other common causes of pleural effusion, and a thorough evaluation is still warranted 1