rare skin diseases

Rare Skin Diseases

Skin diseases range from being mild inconveniences to major health threats. Your skin is actually the largest organ of your body. So, when you have a skin disease, you shouldn’t take it too lightly. You’ve probably heard of acne, psoriasis, rosacea, and eczema, which are skin diseases. You also know about skin cancer, as it is the most common cancer in the US.

While most skin diseases are treatable, some are rare, or very rare. There’s confusion around rare skin diseases. This is because there’s limited research and often mimic common diseases. The Institute of Health has a list of hundreds of rare skin diseases.

As a general rule, many different skin diseases share similar symptoms. A doctor can make the right diagnosis, based on physical exams and additional tests. If recommended treatments aren’t working, doctors and patients will research rare skin diseases. This is also done when new or unusual symptoms occur.

In this article, we’ll discuss three rare skin diseases: Raynaud’s disease, Polymorphous (or polymorphic) light eruption, and Stevens-Johnson syndrome.

rare skin diseases like raynaud's disease affects the extremities

Raynaud’s Disease

Raynaud’s disease affects the skin of extremities; the skin of the fingers, toes, nose, and ears. During an acute episode triggered by cold or stress, the skin of the fingers or toes turns white, then blue, and then feels cold and numb. As a person warms up or experiences stress relief, circulation improves and the skin turns red, inflamed, and painful.

Raynaud’s disease develops when arteries in extremities narrow and limit blood supply when exposed to cold or stress. There is still researching going on. Some believe underlying conditions may cause this rare skin disease. Autoimmune diseases such as scleroderma, rheumatoid arthritis, and Sjogren disease may contribute. Plaque buildup in arteries, carpal tunnel, and beta-blocker and anti-migraine drugs could also cause Raynaud’s disease.

Doctors use antinuclear antibody tests to identify underlying causes of Raynaud’s disease.
To treat the skin disease, doctors prescribe calcium channel blockers and vasodilators. In severe cases, patients may require chemical injections and even surgery.

the sun brings out rare skin diseases like polymorphous light eruption

Polymorphous Light Eruption

Do you develop a red rash with tiny bumps or raised patches when you expose your skin to sun rays? If so, you may have a special sensitivity to light called polymorphous (or polymorphic) light eruption. This condition usually appears in the spring and early summer.

The rash typically appears within half an hour to a few hours after sun exposure. It usually resolves itself without scars within 7 to 10 days. In more severe cases corticosteroids or even phototherapy are necessary.

The rash that appears is itchy and there may be a burning, painful sensation. Since this rash is similar to other conditions that may be more serious, it is important to seek medical advice to get the right diagnosis.

Doctors will need to perform a physical examination to diagnose polymorphous light eruption. They may also order a biopsy, blood test, and photo testing.

Females and those with light skin are more likely to develop this condition. It is best to avoid exposure to the sun during peak hours and wear sunscreen at all times when outside.

Polymorphic light eruption is different from solar urticaria, which is an allergic reaction to the sun and causes hives.

medications could cause the rare skin disease stevens-johnson syndrome

Stevens-Johnson Syndrome (SJS)/Toxic Epidermal Necrolysis

Stevens-Johnson syndrome (SJS) is also known as toxic epidermal necrolysis. It’s a rare skin disease that is life-threatening and needs emergency medical treatment. The skin disease is often a reaction to a medication.

Early signs and symptoms seem harmless, as they mimic flu: a sore throat, fever, and fatigue. These flu-like symptoms last one to three days. They’re then followed by a red or purplish rash that spreads across the body. Blisters will start to form on the skin. The rash is painful and skin can start to shed a few days after the development of blisters. The disease also affects mucous membranes on the genitals and face including the mouth, nose, and eyes.

Drugs linked to the development of SJS include:

  • Allopurinol (used to treat gout)
  • Some antibiotics
  • Anti-seizure medication
  • Antipsychotic medication
  • Naproxen
  • Tylenol
  • Ibuprofen

Reactions can take place up to two weeks after using medications.

Infections such as HIV and pneumonia are also linked to cases of SJS.

Treatment of SJS includes:

Risk factors for SJS include a weakened immune system, previous history of this condition, and certain genetic factors. Left untreated, SJS and its more severe form, toxic epidermal necrolysis, can lead to sepsis, eye damage, skin damage, and respiratory failure.


With the skin being the largest organ of our bodies, it’s important to take care of it. Learn about rare skin diseases and their symptoms so you can identify them and treat them as needed.

Remember to always wear sunscreen when outside and exposed to the sun’s rays, too. Take care of your skin and pay attention to it.