Angioedema (allergic, idiopathic, or hereditary)

Painless swelling, most often affecting the face, lips, and sometimes tongue

Sometimes itching or tight sensation

Swelling that does not remain indented after being pressed (nonpitting swelling)

Only a doctor's examination

A blood clot in a deep-lying vein in a leg (typically), an arm, or the pelvis (deep vein thrombosis)

Sudden swelling

Usually pain, redness, warmth, and/or tenderness in the affected area

If the clot travels and blocks an artery to the lung (pulmonary embolism), usually shortness of breath and sometimes coughing up blood

Sometimes in people who have risk factors for blood clots, such as recent surgery, an injury, bed rest, a cast on a leg, hormone therapy, cancer, or a period of immobility such as a long airplane flight

Ultrasonography

Sometimes a blood test to detect blood clots (D-dimer)

Chronic venous insufficiency (causing blood to pool in the legs)

Swelling in one or both ankles or legs

Chronic mild discomfort, aching, or cramps in the legs but no pain

Sometimes reddish brown, leathery areas on the skin and shallow sores on the lower legs

Often varicose veins

Only a doctor's examination

Painless swelling in both legs and feet

Only a doctor's examination

Heart failure

Painless swelling in both legs and feet

Often shortness of breath during exertion or while lying down and during sleep

Often in people known to have heart disease and/or high blood pressure

Chest x-ray

ECG

Echocardiography

Infection of the skin (cellulitis)

An irregular area of redness, warmth, and tenderness on part of one limb

Swelling

Sometimes fever

Only a doctor's examination

Infection deep under the skin or in the muscles (rare)

Deep, constant pain in one limb

Redness, warmth, tenderness and swelling that can feel tight

Signs of severe illness (such as fever, confusion, and a rapid heart rate)

Sometimes a foul discharge, blisters, or areas of blackened, dead skin

Blood and tissue cultures

X-rays

Sometimes MRI

Kidney disease (mainly nephrotic syndrome)

Widespread, painless swelling

Often fluid within the abdomen (ascites)

Sometimes puffiness around the eyes or frothy urine

Blood tests to evaluate kidney function

Measurement of protein in a urine specimen

Liver disease if chronic

Widespread, painless swelling

Often fluid within the abdomen (ascites)

Causes that are often apparent based on history (such as alcohol use disorder or hepatitis)

Sometimes small spiderlike blood vessels that are visible in the skin (spider angiomas), reddening of the palms and, in men, breast enlargement and a decrease in the size of the testes

Other blood tests to evaluate the liver

Lymphatic vessel obstruction due to surgery or radiation therapy for cancer

Painless swelling of one limb

A cause (surgery or radiation therapy) that is apparent based on history

Only a doctor's examination

Lymphatic filariasis (a lymph vessel infection due to certain parasitic worms)

Painless swelling of one limb and sometimes the genitals

In people who have been in a developing country where filariasis is common

Examination of a blood sample under a microscope

Normal swelling

A small amount of swelling of both feet and/or ankles that occurs at the end of the day and resolves by morning

No pain, redness, or other symptoms

Only a doctor's examination

Pregnancy or a normal premenstrual symptom

Painless swelling in both legs and feet

Usually relieved to some extent by rest and leg elevation

In women known to be pregnant or about to have a menstrual period

Only a doctor's examination

Pregnancy, with preeclampsia

Painless swelling in both legs and feet and sometimes hands

High blood pressure (often new)

Usually occurring during the 3rd trimester of pregnancy

Measurement of protein in urine

Pressure on a vein (for example, by a tumor, pregnancy, or extreme abdominal obesity)

Painless swelling that develops slowly

Ultrasonography or CT if a tumor is suspected