Doctors usually classify edema as either pitting or non-pitting. If you press a swollen area with your finger and it doesn’t cause an indentation in the skin, it’s considered non-pitting edema.
Areas of pitting edema respond to pressure, usually from a hand or finger. For example, when you press on the skin with your finger, it’ll leave an indentation, even after you remove your finger. Chronic pitting edema is often a sign of liver, heart, or kidney problems. It can also be a symptom of a problem with nearby veins.
Applying pressure to non-pitting edema, on the other hand, doesn’t cause any lasting indentation. It’s often a sign of a condition affecting the thyroid or lymphatic system.
Lymphedema is a condition that makes it difficult for lymph fluid to properly drain due to a blockage. It’s often caused by a surgical procedure or as a secondary condition. You can also be born with it.
When lymph fluid can’t drain it accumulates and causes swelling. Lymphedema can be either pitting or non-pitting.
Some people with severe or advanced hypothyroidism develop a condition called myxedema. It tends to cause swollen legs and feet, but it can also cause swollen eyelids and lips. In some cases, it can also cause tongue swelling.
Lipedema causes fat cells to grow and proliferate, and leads to increased fluid retention around the cells which results in non-pitting edema that’s often tender or painful. It usually affects the legs and feet and occurs almost exclusively in women.
If you have unusual swelling, there are several things your doctor can do to determine the cause. They’ll likely start by applying pressure to the area to see whether your edema is pitting or non-pitting.
If you’ve recently had a lymph node removed, they may use lymphoscintigraphy. This is an imaging test that uses a radioactive substance to see how fluid travels through your lymphatic system. Depending on your medical history, they may be able to diagnose lymphedema with a basic physical exam.
They may also perform a thyroid function test to measure your thyroid-stimulating hormone (TSH) levels, along with your thyroxine (T4) levels. Low T4 levels, along with high TSH, indicate hypothyroidism which causes myxedema. If you’ve already been diagnosed with hypothyroidism, you may not need any other tests to diagnose myxedema.
Lipedema can be harder to diagnose because it doesn’t always show up in imaging tests. Instead, your doctor will likely examine you for physical signs, such as:
- easy bruising
- unaffected feet
- excess weight that doesn’t respond to diet or exercise
Non-pitting edema is usually harder to treat than pitting edema. Pitting edema is often due to extra water, so it responds well to elevation and diuretics. Non-pitting edema, on the other hand, is usually caused by factors other than just fluid, which makes drainage more difficult.
Lymphedema usually responds well to complex decongestive therapy (CDT). This involves:
- using gentle massage to stimulate fluid movement and open up lymphatic capillaries
- wrapping the area with bandages
- following a skin care routine to keep the affected area moisturized
- getting regular exercise
- wearing compression garments
While there’s no treatment for lipedema, many people find that CDT also works well for lipedema symptoms. Lipectomy, a modification of liposuction, may also help with lipedema in its earlier stages.
Myxedema usually requires medication, such as a synthetic T4 hormone called levothyroxine. This will help to restore the balance of your thyroid hormones. Keep in mind that it may take a few weeks for this treatment to start working.
If left untreated, non-pitting edema can cause a range of complications. As your skin stretches in response to swelling, it can become dry and cracked, leaving it vulnerable to infection. Over time, the swelling can also permanently scar the deep tissue beneath the affected area. It can also lead to poor circulation and increase your risk of developing ulcers.
The cause of myxedema can lead to something called a myxedema crisis. This is a medical emergency that causes:
- decreased breathing
- low body temperature
- low blood oxygen
- high blood carbon dioxide
- low blood sodium
A myxedema crisis can also cause death, so it’s very important to seek immediate treatment.
Non-pitting edema is usually a sign of an underlying condition, so it’s best to have your doctor take a look at the affected area. Depending on the cause, you may need massage therapy, medication, compression garments, or a combination of all three.