Alejandro Floh, BSc
Medical student,
University of Toronto
Co-authored by:
D'Arcy L. Little, MD, CCFP
Director of Medical Education and Research
York Community Services, Toronto, ON
Introduction
Family physicians are frequently faced with patients who complain of the swelling of one or both of their legs. Although many cases of leg swelling are benign, a systematic approach is necessary in order to avoid overlooking a potentially serious condition.
The principle cause of leg swelling is edema.2 Edema is a general term that refers to a "clinically apparent increase in interstitial volume"1, which arises from capillary filtration that exceeds lymphatic drainage.
History
A comprehensive history is the first step in making a diagnosis of leg swelling. Initially, leg swelling should be classified into two broad categories: unilateral versus bilateral, and acute versus subacute or chronic. In general, this classification should allow one to differentiate between local diseases, which are usually unilateral, and manifestations of systemic conditions, that present as unilateral or bilateral swelling. Major local conditions include deep vein thrombosis (DVT), superficial thrombophlebitis, and cellulitis. Systemic illnesses such as congestive heart failure (CHF), cirrhosis, nephrotic syndrome, and malnutrition usually present with bilateral swelling of the lower extremities.