What is the workup for peripheral edema (swelling of the feet)?

From the Guidelines

A workup for feet swelling should begin with a thorough medical history and physical examination to determine the underlying cause, including assessment of bilateral versus unilateral swelling, timing, associated symptoms, and medication review, as recommended by the most recent guidelines 1. The initial evaluation should include laboratory tests such as complete blood count, comprehensive metabolic panel, thyroid function tests, and urinalysis to evaluate for kidney, liver, or thyroid dysfunction.

• Additional tests may include B-type natriuretic peptide (BNP) for heart failure, D-dimer if deep vein thrombosis is suspected, and albumin levels to check for protein deficiency.
• Imaging studies like duplex ultrasound can identify venous insufficiency or thrombosis, while echocardiography may be necessary if cardiac causes are suspected.
• Chest X-ray can help evaluate for pulmonary conditions contributing to right heart failure. Management depends on the underlying cause, ranging from diuretics for fluid retention, compression stockings for venous insufficiency, to specific treatments for conditions like hypothyroidism or heart failure, as suggested by previous studies 1. Lifestyle modifications including leg elevation, sodium restriction, and regular exercise are often beneficial regardless of etiology, and swelling that is severe, sudden, accompanied by shortness of breath, chest pain, or occurs after prolonged immobility requires immediate medical attention as these may indicate serious conditions requiring urgent intervention 1.

From the Research

Causes of Feet Swelling

• Edema is an accumulation of fluid in the interstitial space that occurs as the capillary filtration exceeds the limits of lymphatic drainage, producing noticeable clinical signs and symptoms 2
• The chronic accumulation of edema in one or both lower extremities often indicates venous insufficiency, especially in the presence of dependent edema and hemosiderin deposition 2
• Obstructive sleep apnea may cause bilateral leg edema even in the absence of pulmonary hypertension 2
• Brawny, nonpitting skin with edema characterizes lymphedema, which can present in one or both lower extremities 2
• Possible secondary causes of lymphedema include tumor, trauma, previous pelvic surgery, inguinal lymphadenectomy, and previous radiation therapy 2

Diagnostic Approach

• A thorough history and physical examination and a carefully considered laboratory and imaging evaluation are critical in differentiating causes of lower limb edema 3
• A diagnostic algorithm that incorporates a systematic approach to the patient with leg swelling and provides an efficient pathway for the differential diagnosis for this problem can be useful 3
• Common etiologies of leg swelling include systemic, superficial, and deep venous, and lymphatic disorders 4

Management Options

• Skin care is crucial in preventing skin breakdown and venous ulcers in patients with edema 2
• Eczematous (stasis) dermatitis can be managed with emollients and topical steroid creams 2
• Patients who have had deep venous thrombosis should wear compression stockings to prevent postthrombotic syndrome 2
• Use of pneumatic compression devices or compression stockings may be helpful in cases of lymphedema 2