This wonderful post came from Dr. Hayes (you can read the original article here)
When the immune system works the way it supposed to, immune cells attack things that shouldn’t be in our system like viruses and bacteria. However, autoimmune diseases happen when your immune system starts to see healthy, normal cells in your body as foreign invaders and, in turn, attacks them. Your immune system may see cells in specific organs as foreign and sometimes manifest as rashes on the skin. This can also show up in the joints as redness and swelling. The common theme between all autoimmune diseases is inflammation. Some autoimmune diseases restrict themselves to certain organs (for example, Graves’ disease, which for the most part, is a disease that only attacks the thyroid). Other diseases like lupus can affect almost any part of the body.
How do autoimmune diseases happen?
We don’t completely understand why autoimmune diseases occur. Some people are genetically predisposed to these diseases. We do know that certain ethnic groups tend to get autoimmune diseases more often than others. It’s also possible that an outside influence like a virus may trigger the disease.
Where does dermatology fit into autoimmune diseases?
As a dermatologist, I see autoimmune diseases on a regular basis. There are certain autoimmune diseases that have classic findings on the skin. This is very important to recognize because, when I see a skin problem that looks concerning for an autoimmune disease, it may be a sign that there are internal problems in the body as well. Fortunately, there are treatments for this.
Below, I have listed some of the more common autoimmune diseases. The diseases that involve the skin are listed in bold.
The most common autoimmune disease that I see involving the skin is lupus. Many people reading this article may know someone with lupus. One of the more common symptoms of lupus is a photosensitive skin rash. This means that when a person with lupus goes out into the sun, they feel sick or develop a rash. The rash most commonly seen with systemic lupus is the “malar” (butterfly) rash that covers the cheeks and nose.
The sun can trigger a flare-up of the disease and the malar rash is a warning sign that the disease is active. The rash is important to recognize because, when lupus is untreated, it has the potential to cause damage to other organs such as the kidneys, lungs or heart. Systemic lupus can affect almost any organ. Other skin findings with systemic lupus are dilated blood vessels around the cuticles or ragged cuticles. Rashes can also occur on any area that is exposed to the sun. Skin problems may be one of the first symptoms of lupus, so sensitivity to sunlight is not something to take lightly.
One type of lupus called Subacute Cutaneous Lupus doesn’t typically have internal involvement. Instead, it just presents itself with sun-sensitive rashes.
How does a person know if they have the autoimmune disease lupus?
The diagnosis is made when a person meets a certain number of diagnostic criteria. One needs to have 4 of the following problems to be diagnosed with lupus:
1. Skin rashes: either a malar rash, discoid rash (somewhat circular-shaped scarring skin lesions) or a rash on sun-exposed areas
2. Mouth sores
4. Pleurisy (inflammation of the lungs) or pericarditis (inflammation of the heart)
5. Abnormal blood tests such as low white blood cell counts or platelets
6. Kidney problems
7. Neurologic problems such as psychosis or seizures
8. Abnormal autoantibody tests such as a positive ANA (anti-nuclear antibody test); Almost all patients with lupus have a positive ANA. However, many people without lupus have a positive ANA as well so it’s important for this to be interpreted by a Rheumatologist specialist.
For those that do have lupus, one of the most important practices to prevent flare-ups of the disease is meticulous sun protection. Sunscreen should be used on a daily basis that contains a physical
blocker like zinc.