Category: TRAINING

No one is truly allergic to the sun, but some people are quite sensitive to different types of sun rays and may develop mild to serious reactions after spending time in the sun.

There are several types of “sun allergies,” but polymorphous light eruption (PMLE), an autoimmune condition in the skin that occurs after sun exposure, is one of the most common. Other conditions considered as sun allergies are solar urticaria (hives and reddish patches that usually start 30 minutes to two hours after the sun exposure), actinic prurigo (papules and nodules that are intensely itchy on sun-exposed skin areas), and photoallergic reaction (when the UV rays from the sun modify the chemical structure of medications or products applied to the skin, and a person develops an allergy to the newly modified substance).

What causes PMLE?

People who have PMLE have immune cells that are triggered by sun rays, which attack their skin, and they develop a skin reaction to the sun’s the ultraviolet (UV) rays.

PMLE represents 70% of all sun-induced skin eruptions. It can affect both sexes and all skin types, and it usually starts when someone is a teen or young adult. PMLE may be an inherited condition. Being a female, having fair skin, and living in the north are other risk factors.

PMLE is more common in young women who live in temperate climates. People who live in temperate climates spend all winter out of the sun, so when it becomes warmer the sun exposure is intense. People who live in warmer climates are desensitized because they have a higher sun exposure all year.

What does PMLE look like?

PMLE can appear several hours or days after the first major sunlight exposure of the season, usually during spring or at the beginning of summer. The areas of the body generally affected the most are the ones that are covered during wintertime, but not in the summer: the neck, the chest, and the outer parts of the arms.

After exposure to the sun, people with PMLE usually notice reddish patches on their skin. These spots may itch, burn, or sting, but they typically don’t leave a scar. In more severe cases, the patches cover most of the body and may also be associated with headaches, fevers, tiredness, and low blood pressure. (If you experience these symptoms, see an urgent care provider for evaluation.) If you think you have PMLE or another sun allergy, a dermatologist is the best doctor to evaluate and treat your skin condition.

Does PMLE get better?

PMLE lesions often get better in approximately 10 days, and it’s important to avoid sun exposure until you are healed. People who develop PMLE can experience significant discomfort and have their life negatively impacted during the spring and summer months. However, repetitive sun exposure can make PMLE less likely to occur. The hardening effect, as it is called, means that the skin lesions that appear after the first episode are less severe, and they can be better tolerated during subsequent episodes.

What are current treatments for any sun allergy, including PMLE?

The best treatment is to prevent sun exposure. Avoid sunlight when it is most intense (from 10 a.m. to 4 p.m.), and use UV-protecting clothing or clothes made of darker and thicker fabrics, as they will prevent the UV rays coming from the sun from reaching your skin. Hats with a wide brim protect your scalp, face, and (partially) the neck.

Broad-spectrum sunscreens that protect your skin from both UVA and UVB rays should be used daily, even if it’s cloudy. Apply sunscreen on your face and any part of your skin that is not covered by a hat or clothing. Reapply sunscreen every two hours, and if you go swimming or get sweaty reapply more frequently (water-resistant sunscreen should also be reapplied).

If you develop PMLE, the areas of skin impacted can be treated with steroid creams. In severe cases, your doctor may recommend a short course of steroid pills. Medications that reduce the immune response, such as azathioprine, are options for treating PMLE, since it is an autoimmune condition (the body is attacking it is own healthy cells).

Antihistamines are medications typically used for allergies that may help shorten the duration of reddish patches that itch or burn, and they also reduce inflammation.

Hydroxychloroquine (a medication also used to treat malaria) can be used in case of flare-ups, or as a prevention method when people travel to sunny locations during winter vacations.

Oral Polypodium leucotomos extract, a natural substance derived from tropical fern leaves, may work as a potent antioxidant, and has anti-inflammatory properties that are beneficial in the prevention of PMLE. Other nutritional supplements containing lycopene and beta-carotene (vitamin A derivatives) have a similar effect. A dermatologist will guide you on the best way to use these medications.

The bottom line

Sun allergies are common in temperate climates, but with a dermatologist’s guidance, vigilant sun prevention, and medications they can be managed throughout the sunny months of the year.

About the Authors

Neera Nathan, MD, MSHS, Contributor

Dr. Neera Nathan is a dermatologist and researcher at Massachusetts General Hospital and Lahey Hospital and Medical Center. Her clinical and research interests include dermatologic surgery, cosmetic dermatology, and laser medicine. She is part of the … See Full Bio View all posts by Neera Nathan, MD, MSHS

Lais Lopes Almeida Gomes, Contributor

Dr. Lais Lopes Almeida Gomes is a dermatology research fellow at Massachusetts General Hospital, and a pediatric dermatologist in Brazil. Her clinical and research interests include atopic dermatitis and global health. She is part of the … See Full Bio View all posts by Lais Lopes Almeida Gomes

Chronic kidney disease (CKD) affects an estimated 37 million people in the United States. Often, it begins and progresses silently, causing no obvious symptoms until kidney function is severely impaired. During early stages, up to nine in 10 people aren’t aware that they have it.

If kidney disease is caught early and treated properly, serious problems may be avoided. Once kidneys fail, ongoing dialysis or kidney transplant is necessary. But barriers to care are highest for Black and Hispanic people with advanced kidney disease, and also for younger adults ages 22 to 44, according to a recent study.

How does kidney disease affect the body?

As a doctor who focuses on patients with kidney disease, I’ve found that it helps to explain a few basics. Our kidneys have several jobs. Their most important task is to regularly remove toxins from the bloodstream and excess water from the body by making urine.

If you have CKD, your kidneys are not removing toxins from your blood as well as they should. At its most severe, this can progress to end-stage kidney disease (ESKD), which is when the filtering capacity of your kidneys is reduced enough to make you feel ill.

If this occurs, two main forms of treatment can replace your kidney function: dialysis or a kidney transplant. Dialysis can be performed at a treatment center, or at home after appropriate training. Transplant surgery and post-surgical care occur at specialized centers.

What causes kidney disease?

High blood pressure, diabetes, and high cholesterol are three common risk factors for developing chronic kidney disease. Smoking, obesity, and frequent use of over-the-counter anti-inflammatory medicines, such as ibuprofen or naproxen, worsen kidney function over time.

Severe cases of COVID-19 requiring hospitalization have emerged as a separate risk factor for CKD. And genetic factors may predispose a person to kidney disease as well.

Gaps in kidney care are contributing to health disparities

Statistics show that people who are non-Hispanic Black, Hispanic, and Native American bear a disproportionate burden of kidney disease. For example:

• For every white person who develops ESKD, three Black people develop it.
• While non-Hispanic Black patients make up only 13% of the US population, they represent 35% of people currently on dialysis.
• Among patients initially on a wait list for a kidney transplant in 2014, median wait times were approximately 64 months for Black patients, 57 months for Hispanic patients, and 37 months for white patients.

Most likely, disparities in CKD reflect a combination of the social determinants of health, genetics, and a higher burden of other diseases that contribute to kidney disease, such as high blood pressure and diabetes. Barriers to getting proper treatment — particularly early treatment — play a role, too.

A recent retrospective study in the American Journal of Kidney Medicine suggests age is also a factor. The researchers reviewed data from more than 800,000 patients who received dialysis at home, dialysis at a treatment center, or a kidney transplant between 2011 and 2018. They found

• white people in the study were more likely than people of color to use at-home dialysis or receive a kidney transplant within 90 days.
• the care gap was greatest among adults ages 22 to 44. Black patients in this age group were 79% less likely, and Hispanic patients were 53% less likely, than white patients to receive a kidney transplant within 90 days.

These disparities may be driven partly by the fact that Black and Hispanic patients are less likely to receive appropriate early-stage kidney care, and by differences in insurance. They may also be less likely to have access to a living kidney donor. An important limitation of this study is that these findings cannot be applied to other minority groups.

The bottom line

The good news is that most people can prevent kidney disease by following healthy lifestyle habits, such as eating a low sodium diet, getting moderate exercise, not smoking, and minimizing alcohol intake. If you have high blood pressure, diabetes, high cholesterol, or heart disease, you should be tested for kidney disease once a year. High blood pressure and diabetes — which occur more often among Black Americans and people of color in the US than among white Americans — harm kidneys. Studies such as the one described above increase our understanding of health disparities in kidney disease, with the hope of one day coming up with an equitable solution for everyone, no matter their background or age.

About the Author

Christopher Estiverne, MD, Contributor

Originally from New Jersey, Dr. Christopher Estiverne is currently a staff nephrologist at Brigham and Women’s Hospital in Boston, where he specializes in care of patients with chronic kidney disease. He completed his medical degree and … See Full Bio View all posts by Christopher Estiverne, MD