Protoporphyrias

EPP/XLP symptoms are caused by light, usually sunlight, shining on your skin. It is important to know that not all sun protection advice and products will work to protect your skin. This is because most sun protection is related to UV light, and the type of light that triggers porphyria skin symptoms is blue-violet light. Light is often referred to by its wavelength: the blue-violet wavelengths that affect porphyria are around 400 nm (~370-430 nm).

Blue-violet light is present in sunlight and can also be found in some fluorescent lights and LED lights, computer and phone screens. Light that is passing through a window, reflected off of water or snow can also trigger symptoms. Many types of LEDs and incandescent lights are safe.

Some strategies and tips to protect yourself blue-violet light include:

• Clothing: double layers or thick, dark fabrics will block out more light. Long sleeves, wide-brimmed hats, sunglasses, buffs and gloves can help keep you covered. Many people find clothing specifically for sun and UV protection to be helpful. Sun-protective clothing can be found at outdoor stores.

• Protecting your hands: Skin on your hands is often exposed to light and may be delicate, and more prone to injury. Gloves can both protect your hands from light and prevent injuries when doing outdoor activities like gardening.

• Stay in the shade: You can also consider carrying an umbrella to make your own shade.

• Sunscreen: most sunscreens don’t block blue-violet light and won’t protect your skin from porphyria. Some people find opaque or mineral sunscreens are helpful. Look for ingredients like zinc oxide or titanium oxide. These sunscreens sit on top of your skin and form a reflective barrier. Some are tinted, which can help them blend in better. Fake tanners and foundation may also help block light from hitting your skin.

• Windows: regular windows do not block blue-violet light. Windows can be tinted or covered with vinyl films that filter out blue light (they are usually yellow). Car windows can also be tinted- though it is important to check your local laws about window tinting.

• Indoor lights: dimmers, shades and filters can reduce light intensity. Look for “warm white” light bulbs- they generally have less blue light.

• Screens: most phones and computer screens will let you turn on a “night mode” that reduces blue light.

• Identifying blue light sources: some people with EPP find a photography app (EVO LightSpectrumPro) helpful to identify light sources with a lot of blue light.

• Ask for accommodations: under human rights legislation in Canada, employers and schools are required to provide reasonable accommodations for disability. If there are steps your employer or school could take, such as changing lights, adding window films or moving your workspace away from windows, you can make a request and your workplace should take reasonable steps to accommodate you.

The pain and symptoms caused by light exposure (called a phototoxicity) will generally take 4-7 days to resolve. During that time, different strategies you can try to manage your pain include:

• Cold water or compresses on the skin, some people report that steam and warm water also help

• Fans blowing cool air

• Avoiding heat sources and additional light

• Oral corticosteroids and anti-histamines, are sometimes used to manage pain and swelling, though it is unclear how effective they are. No pain medications, including narcotics appear to relieve pain.

Vitamin D deficiency is very common for people with EPP and XLP because sun exposure is important for your body to make Vitamin D. This deficiency can cause low bone density (osteopenia, osteoporosis) which can put you at higher risk for broken bones (fractures).

Vitamin D supplements are recommended and your vitamin D levels should be monitored annually.

Low iron levels are common in EPP and XLP, however iron supplements (including iron in multivitamins) should not be taken without consultation with a porphyria specialist because it can make your condition worse.

EPP AND IRON

If you have EPP, iron supplements can make your skin sensitivity worse and may increase the likelihood of liver damage. Iron supplementation may be particularly risky if you already have high protoporphyrin levels or liver damage.

Your iron levels should be monitored regularly. If your iron drops below your usual levels and/or you are experiencing the negative effects of anemia (ex. fatigue, shortness of breath) from low iron, you may want to consider treatment. Iron supplementation should be done in consultation with, and closely monitored by, your porphyria specialist. It is suggested to use a low, oral dose and complete the treatment during the winter.

XLP AND IRON

It appears that iron supplements may improve symptoms for some people with XLP. You should still consult with your doctor, however, before using iron supplements.

In general, people with EPP and XLP do not need to follow any special diets or avoid particular foods. Due to the risk of liver disease, however, people with EPP and XLP are advised to avoid or moderate their alcohol consumption.

The experience of having EPP or XLP can have a profound impact on your mental health.

Avoiding the sun can be very isolating. It is hard to maintain relationships while avoiding light exposure and managing symptoms. You may not know anyone else with porphyria and it can be hard to explain the realities of your condition to people who don’t have it. Many people with porphyria also have had negative, sometimes traumatic, experiences in the medical system, including being told that their symptoms are “in their head” or having their care needs or symptoms minimized or ignored. Family members and friends may also minimize or disbelieve their experiences.

It is important to look after your mental health. In addition to general health advice such as eating well, practice good sleep hygiene and exercising regularly, you may find the following helpful:

• Ask your doctor for support to manage anxiety and depression symptoms

• Seek professional support from a counsellor or psychologist

• Connect with others who have similar experiences: read stories, attend patient gatherings and join supportive online groups

• Incorporate meditation or other practices into your daily routine

Children with EPP and XLP are often set apart from their peers, and growing up with a skin porphyria can be extra isolating. The American Porphyria Association’s Shadow Jumpers has stories, tips and tricks from other children living with EPP and their parents. There is a summer camp, Camp Sundown, for children who cannot go out in the sun and their families. Each year the Canadian Association for Porphyria supports families to attend Camp Sundown.

In a small number of EPP and XLP cases, liver failure can occur ( see Liver Disease and EPP/XLP above). Liver failure can occur quickly, so it is important that your liver function is monitored regularly, and you should seek treatment immediately if you have signs of liver failure (yellow eyes and skin, abdominal pain, increased intolerance to sunlight).

Why some people with EPP/XLP develop liver damage and others don’t is not well understood. There are steps you can take, however, reduce your risk and protect your liver:

• Moderate or avoid alcohol consumption

• Get vaccinated against Hepatitis A and B

• Limit the use of drugs and herbal preparations known to cause liver issues, particularly drugs that cause cholestasis (slowing the flow of bile from your liver). These drugs include- among others- estrogens, anabolic steroids and some types of antibiotics.

Some lights used in medical procedures and dental work may trigger a reaction. Additional precautions should be taken:

• The blue lasers used by dentists for cavities can burn your gums. Care should be taken when directing the light.

• Bright surgical lights should generally be safe, however, the surgical team should be made aware of your light sensitivity and yellow filters over lights can be used to reduce risk, particularly for long surgeries. Using these filters is especially important if you have liver damage related to EPP/XLP. In these cases, the use of surgical lights can cause a reaction on the inside of the body.

• The lights used for laser eye treatments and laser hair removal have been done with no reported problems.

• The lights used for endoscopies are generally safe, though if you have severe liver-disease the doctor should consult with a porphyria specialist before the procedure.

Many people worry that they will pass on their porphyria to their children. EPP is a genetic condition, which means that you can pass on the genes that cause porphyria. This does not mean, however, that your children will have your condition. You can ask for a referral to a genetic counsellor to better understand how your children are likely to be affected.

KEY TAKE-AWAY

The risk of your children inheriting EPP will depend on your partner’s genes. To understand your risk, your partner will need to be tested for a low function or severe gene variant.

THE SCIENCE

EPP is what’s called an autosomal recessive disorder. What this means is:

• Autosomal: the sex of the person will not affect the likelihood of passing on the gene (the gene is not on a sex chromosome). Because everyone has two copies of each autosomal gene, the likelihood of a parent passing on an autosomal gene to a child of either sex is 50%.

• Recessive: Everyone has two copies of each type of autosomal gene. If the gene is recessive, that means you need two copies of the gene variant in order to have the condition (so one from each parent).

EPP inheritance is more complicated than many other recessive disorders because there are three different variations of the gene, and it is the combination of the different variants that causes EPP:

• Severe variant: you will need at least one copy of the severe variant to have EPP

• Low function variant: having a copy of this gene variant is fairly common in the general population and will only be a problem if combined with the severe variant

• Normal variant: if you have at least one copy of this variant, you will not have EPP, though you may be a carrier of the severe variant

Most people with EPP will have one severe variant and low function variant. Each of those genes has a 50% chance of being passed on to your children. Because you need two copies of a non-normal variant, including one that is severe, the likelihood of your child inheriting EPP depends on the genes of the other parent:

• If the other parent has two normal copies, your child will not have EPP but there is a 50% chance they will be a carrier of the severe variant

• If the other parent has a low function variant or is a carrier for the severe variant, there is a chance that your child will have EPP.

XLP is an X-linked genetic condition which means that the gene causing XLP is on a sex chromosome (the X chromosome). This means that the inheritance pattern will depend on the sex of the parent and child.

MALES WITH XLP

Males have two different sex chromosomes- an X and a Y. Because they only have one copy of the X, if their X chromosome has the gene variant for XLP, they will have XLP.

For fathers with XLP this means:

• All of their daughters will receive a copy of their X chromosome. They will have the XLP gene.

• All of their sons will receive of their Y chromosome. This means that they will not have XLP.

FEMALES WITH XLP

Females have two X chromosomes. This means that they will have two copies of the gene. If one of X chromosomes has the variant for XLP, they may or may not have symptoms.

• All of their sons and daughters will have a 50% chance of inheriting a copy of the XLP variant. If their sons get the variant they will have XLP.

In cases where there are two X chromosomes, it can be difficult to predict if you will have symptoms. This is because cells usually only use one copy of their X chromosome, so whether or not you have symptoms will depend on if cells are using the copy with the XLP variant or not.