Sun sensitivity, sun allergies & PLE

Aug 12, 2017

For many people, one of the joys of summer is spending time in the sun. But other people are extremely sensitive to sun. And some people can have an allergic reaction to the sun called polymorphous light eruption.

This week on “Take Care,” Dr. Rosemarie Ingleton, professor of dermatology at Mount Sinai Hospital, discusses sun sensitivity and polymorphous light eruption. Ingleton is also an instructor at the Albert Einstein College of Medicine.

Ingleton says sun sensitivity can be described as someone who sunburns very quickly, “within seconds or minutes” when someone with a similar skin tone is not burning that quickly.

Being sun sensitive or sun toxic can occur for a few different reasons. You could be taking a medication that makes your skin more sensitive to the sun, or applying a product that does, says Ingleton.

For example, many topical treatments for acne can increase your skin’s sun sensitivity. Retinoids, vitamin-A based creams and benzoyl peroxides are among the culprits.

Oral medications that can cause sun toxicity include oral antibiotics for treating acne, diabetic control medicines, some high blood pressure medicines and even birth control pills.

Also, Ingleton says certain underlying medical conditions can make patients inherently photo sensitive.

So when is sun sensitivity diagnosed as polymorphous light eruption, or PLE?

It can be difficult to tell if you have polymorphous light eruption. PLE is considered polymorphous because it can look different on different people. Ingleton says it can appear on the skin as little bumps, a big red patch, or a hive.

Ingleton says PLE seems to be a seasonal thing. It comes on in late spring and usually peters out as summer goes on. Typically it appears on the arms or on the chest – or as Ingleton describes it, the part of your body that shows when you’re wearing a V-neck shirt. She says sometimes it itches or is red or bumpy.

Ingleton says it’s an autoimmune response.

“Your skin’s immune cells are just misbehaving,” she says.

Ingleton says PLE can seemingly come out of nowhere. Many people say they get their first episode in their late teens or 20s.

“It seems to be a very sporadic, weird, out-of-the-blue kind of condition,” Ingleton said.

The typical pattern of the disease is that patients tend to get it every year for a few years or many years. But there is an end point, Ingleton says.

Patients diagnosed with PLE are mostly women, but it’s not strongly found among family members. It’s more common in areas with a distinct change in temperature – the northern parts of the world where there is a cold season followed by hot months. Ingleton says it’s not seen much in climates where it’s hot year-round.

So how do you know if what you have is PLE and not a rash or other allergic reaction? Ingleton says a diagnosis is dependent on seeing an actual eruption on the skin. Every now and then it’s necessary to have a skin biopsy performed to see exactly what it is. Sometimes a blood test can help distinguish PLE from other conditions.

If you suspect you may have PLE, Ingleton says it’s best to go see a dermatologist.

The number one protection against PLE is wearing sunscreen. Ingleton recommends wearing it on a daily basis during the season.

Once a flare-up occurs, it can be treated with an anti-inflammatory cream, maybe something with a hydrocortisone base to it. Anti-itch products sometimes help.

But Ingleton says for some people, these treatments don’t help. These patients may need to do something called “phototherapy,” which involves being purposefully exposed to certain wavelengths of light, almost to desensitize them. It can help the rash go away. And then in the future, those patients can get phototherapy to help prevent an outbreak.

But, Ingleton says avoidance of the sun, to the best of your ability, is the best way to avoid PLE.