Some Causes and Features of Swelling
Cause | Common Features* | Tests† |
|---|---|---|
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 or darkness, 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, smoking, or a period of immobility such as a long airplane flight | Ultrasound study 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 | |
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 study ECG Echocardiography | |
Infection of the skin (cellulitis) | An irregular area of redness or darkness, 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 or darkness, 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-ray studies 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 | Measurement of albumin in the blood 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 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, especially after sitting or standing, 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 third 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 | Ultrasound study or CT if a tumor is suspected |
* Features include symptoms and the results of the doctor's examination. Features mentioned are typical but not always present. | ||
† A doctor's examination is always done. In most people with swelling, doctors do a complete blood count, other blood tests, and urinalysis (to check for protein in the urine). | ||
CT = computed tomography; ECG = electrocardiography; MRI = magnetic resonance imaging. | ||