Common causes of edema of the extremities include: 1. Kidney causes. Patients with poor renal function may have a decrease in glomerular filtration rate, water and sodium retention as well as a decrease in urine output, and therefore edema may occur, most often starting in the lower extremities of both legs and eyelids, and may subsequently develop throughout the body.2. Patients with liver disease may have edema of the extremities. Liver disease can lead to a decrease in synthetic albumin, which in turn can lead to hypoproteinemia and tissue edema.3. Malnutrition, in which patients have absorption disorders, can lead to a decrease in albumin and thus edema.4. Patients with thyroid function problems may have edema, as well as other endocrine problems that can lead to edema of the extremities, such as common hypothyroidism, secondary or primary aldosteronism, etc., all of which can lead to edema of the extremities. The patient may also have edema in the extremities due to other endocrine problems, such as hypothyroidism, secondary or primary aldosteronism, etc. Cardiac diseases, such as heart failure, are prone to edema in the extremities.