The swelling of the extremities may be caused by two diseases. The first disease is due to the patient’s heart disease, because heart disease may lead to restricted cardiac function, which in this case will cause the patient to have a restricted amount of blood return, thus leading to the appearance of bruising in the extremities, because the bruising is mainly in the capillaries of the extremities, so this situation will lead to swelling in the extremities. Patients are advised to go to the hospital for relevant examinations, such as electrocardiogram and cardiac ultrasound, which can effectively make a diagnosis. After a clear diagnosis, they must be actively treated symptomatically to avoid serious complications. The second disease may also be caused by kidney disease, because kidney disease can lead to renal insufficiency, and patients with renal insufficiency can cause water discharge restriction in the body, this situation will lead to the accumulation of water in the body, and water accumulation is most common in the limbs, so this will also lead to the situation of edema in the limbs. It is recommended that patients should also go to the hospital for relevant examinations, such as renal ultrasound, magnetic resonance imaging and renal function tests, which can effectively make a diagnosis, and after the diagnosis must be actively treated symptomatically.