Lower extremity edema is a multifactorial clinical condition characterized by the abnormal accumulation of interstitial fluid within the subcutaneous tissues of the lower limbs. Clinically, it often presents as visible swelling, which may be either pitting or non-pitting, depending on the underlying etiology. The pathophysiology involves a complex interplay of mechanisms, including increased capillary hydrostatic pressure, decreased oncotic pressure, lymphatic obstruction, and increased capillary permeability. The differential diagnosis is broad, encompassing systemic causes such as congestive heart failure, chronic kidney disease, and hepatic dysfunction, as well as localized factors including venous insufficiency, lymphedema, and trauma. A thorough history and physical examination, complemented by appropriate diagnostic studies such as duplex ultrasonography and laboratory testing, are essential to identify the underlying cause and to inform appropriate management strategies.
