Ewa's sign is seen in:
In pericardial effusion the base of the left lung may be compressed by pericardial fluid, producing a patch of dullness and increased fremitus (and egophony) beneath the angle of the left scapula. This is Ewa's sign. Ref: Harrisons principles of internal medicine, 18th edition, Page: 1971.
Acute pulmonary embolism
Pericardial effusion
Pneumomediastinum
Chronic constrictive pericarditis