Porphyria

Overview

Porphyria (por-FEAR-e-uh) refers to a group of rare disorders that result from a buildup of natural chemicals called porphyrins in the body. Porphyrins are needed to make heme, a part of hemoglobin. Hemoglobin is a protein in red blood cells. It carries oxygen to the body's organs and tissues.

Eight enzymes are needed to change porphyrins into heme. Without enough of any of these enzymes, porphyrins build up in the body. High levels of porphyrins can cause major problems, mainly in the nervous system and skin.

There are two general types of porphyrias. Acute porphyrias start rapidly and mainly affect the nervous system. Cutaneous porphyrias mainly affect the skin. A few types of porphyrias affect both the nervous system and the skin.

Symptoms of porphyria vary, depending on the specific type of porphyria and how severe it is. Porphyria is usually inherited. One or both parents pass along a changed gene to their child.

Although porphyria can't be cured, medicines and certain lifestyle changes may help you manage it. Treatment for symptoms depends on the type of porphyria you have.

Symptoms

Symptoms can vary widely by type of porphyria and in how severe the symptoms are. Symptoms also can vary among people with the condition. Some people with a gene change that causes porphyria never have any symptoms.

Acute porphyrias

Acute porphyrias include forms of the disease that usually cause nervous system symptoms. A few forms also can affect the skin. Symptoms appear quickly and can be severe. Symptoms may last hours, days or weeks.

The most common form of acute porphyria is called acute intermittent porphyria (AIP). AIP may last hours or days. Intermittent means that the symptoms may go away but return later. When the symptoms occur they are sometimes called attacks.

Symptoms of acute porphyrias may include:

• Severe pain in the belly, chest, legs or back.
• Digestive problems, such as constipation, nausea and vomiting.
• Muscle pain, tingling, numbness, weakness or paralysis.
• Red or brown urine.
• Mental changes, such as anxiety, hallucinations or mental confusion.
• Rapid or irregular heartbeats you can feel, called palpitations.
• Breathing problems.
• High blood pressure.
• Seizures.

Cutaneous porphyrias

Cutaneous porphyrias include forms of the disease that cause skin symptoms as a result of sensitivity to sunlight. These forms usually don't affect the nervous system. Porphyria cutanea tarda (PCT) is the most common type of all the porphyrias.

Sun exposure may cause:

• Sensitivity to the sun and sometimes artificial light, causing burning pain in the skin.
• Sudden painful skin redness and swelling.
• Blisters on exposed skin, usually the hands, arms and face.
• Fragile thin skin with changes in skin color.
• Itching.
• Too much hair growth in affected areas.
• Red or brown urine.

Erythropoietic protoporphyria (uh-rith-roe-poi-ET-ik pro-toe-por-FEAR-e-uh), also called EPP, is a rare type of cutaneous porphyria. It's the most common childhood porphyria. Sun or artificial light exposure quickly results in painful skin burning, irritation and swelling. Small bumps and blisters also appear. Repeated exposures can cause thick, leathery skin and scarring.

When to see a doctor

Many symptoms of porphyria are like those of other, more common conditions. This can make it difficult to know if you're having an attack of porphyria. If you have symptoms that could be porphyria, get medical attention. Prompt treatment is important.

Causes

All types of porphyria involve a problem making heme. Heme is a part of hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen from the lungs to all parts of the body. Heme also plays a role in clearing drugs and hormones from the body.

Heme is made in the bone marrow and liver. This process involves eight different enzymes that turn porphyrins into heme. A shortage or change in any of these enzymes causes a buildup of porphyrins. Which enzyme is affected determines the type of porphyria.

In cutaneous porphyrias, porphyrins build up in the skin. When exposed to sunlight, they cause symptoms. In acute porphyrias, the buildup affects the nervous system, causing symptoms.

Genetic forms

Most forms of porphyria are caused by a gene change passed down from one or both parents. Porphyria can occur if you inherit:

• A changed gene from one of your parents (autosomal dominant pattern).
• Changed genes from both parents (autosomal recessive pattern).

Just because you inherit a gene or genes that can cause porphyria doesn't mean that you'll have symptoms. You might never have symptoms. This also is the case for most carriers of the changed genes.

Acquired forms

Porphyria cutanea tarda (PCT) usually is not passed down in families. In PCT, certain triggers can cause a buildup of porphyrins that may cause symptoms. Examples of triggers include:

• Too much iron in the body, often due to a condition called hemochromatosis, which is caused by a gene change.
• Viral infections, such as HIV or hepatitis C.
• Heavy alcohol use.
• Smoking.
• Hormones changes during the menstrual period.

Risk factors

In addition to genetic risk factors, environmental risk factors may trigger symptoms in porphyria. When exposed to the trigger, the body's demand for heme production increases. This overwhelms the low level of a needed enzyme, setting in motion a process that causes a buildup of porphyrins.

Examples of triggers include:

• Exposure to sunlight.
• Certain medicines, for example, birth control pills, sedatives and barbiturates.
• Recreational or illicit drugs.
• Dieting or fasting.
• Smoking.
• Physical stress, such as infections or other illnesses or surgery.
• Emotional stress.
• Alcohol use.
• Hormone changes during the menstrual period.

Complications

Possible complications depend on the form of porphyria:

• Acute porphyrias can be life-threatening if an attack isn't promptly treated. During an attack, you may experience dehydration from loss of fluids, breathing problems, seizures or high blood pressure. You may need a stay in the hospital for treatment. Long-term complications with repeat acute attacks may include long-term pain, chronic kidney failure, liver damage or liver cancer.
• Cutaneous porphyrias can result in permanent skin damage. And the skin blisters can become infected. When your skin heals after symptoms, it may have a changed appearance and coloring, be fragile and slow to heal, or leave scars. Cutaneous porphyrias also increase the risk of liver damage or liver cancer.

In rare cases, a bone marrow transplant or liver transplant may be needed.

Prevention

Although there's no way to prevent porphyria, if you have the condition, avoid triggers to help prevent symptoms.

Because porphyria is usually an inherited disorder, your siblings and other family members may want to consider genetic testing to determine if they have the condition. Genetic counseling is important to help understand test results and risks.

Diagnosis

Many symptoms of porphyria are like those of other more common diseases. Because porphyria is rare, it can be difficult to diagnose.

Lab tests are needed to make a diagnosis of porphyria and to determine which form of the condition you have. The types of tests depend on the type of porphyria your health care provider suspects. Tests include a combination of blood, urine or stool testing to measure porphyrin levels. Other tests may be needed. Genetic tests may be helpful to confirm the diagnosis and determine the type of porphyria you have.

Talking with a genetic counselor can give you information about genetic tests and the risk of porphyria for your children. If you have porphyria, genetic testing and counseling also may be recommended for family members.

Treatment

Treatment depends on the type of porphyria you have and how severe your symptoms are. Treatment includes medicine. It also includes identifying and avoiding symptom triggers, and relieving symptoms when they occur.

Avoiding triggers

To avoid triggers:

• Don't use medicines known to trigger acute attacks. Ask your health care provider for a list of safe and unsafe medicines, including herbal supplements and over-the-counter products.
• Don't use recreational or illicit drugs and avoid heavy drinking.
• Avoid fasting and dieting that involves severe calorie restriction.
• Don't smoke.
• Minimize sun exposure. When you're outdoors, wear protective clothing. Also use an opaque blocking sunscreen, such as one with zinc oxide or titanium dioxide. Use an SPF of at least 30 when you expect a short or limited amount of sun exposure. For longer times outdoors, use an SPF of 50. When indoors, use window filters.
• Treat infections and other illnesses promptly.
• Take steps to reduce emotional stress.
• Talk to your health care provider about options to prevent premenstrual attacks.

Acute porphyrias

Treatment of acute porphyria attacks focuses on providing fast treatment of symptoms and preventing complications. Treatment may include:

• Injections of hemin (Panhematin), a medicine that is a form of heme, to limit your body's production of porphyrins.
• Receiving fluid that contains sugar, also called glucose, through a vein, or sugar taken by mouth, if able. This is done to make sure you get enough carbohydrates.
• A stay in the hospital for treatment of symptoms such as severe pain, vomiting, dehydration or breathing problems.

Givosiran (Givlaari) is a monthly shot for adults with acute hepatic porphyria. In hepatic porphyrias, which include acute intermittent porphyria, the lack of the enzymes needed to make heme occurs in the liver. Givosiran can reduce the number of porphyria attacks. Discuss safety information and potential serious side effects with your health care provider.

Cutaneous porphyrias

Treatment of cutaneous porphyrias focuses on reducing exposure to triggers such as sunlight. It also includes reducing the amount of porphyrins in the body to help relieve symptoms. Reducing porphyrins may include:

• Regularly scheduled blood draws to reduce the iron in your body, which decreases porphyrins. This process is called phlebotomy.
• Taking a medicine used to treat malaria, usually hydroxychloroquine (Plaquenil). This can help absorb excess porphyrins and help your body get rid of them more quickly than usual. The medicine is generally used only in people who can't tolerate phlebotomy.
• A dietary supplement to replace low vitamin D levels caused by avoiding sunlight.

High doses of beta carotene are a common treatment for erythropoietic protoporphyria.

A treatment option only approved for erythropoietic protoporphyria is afamelanotide (Scenesse), a medicine that increases melanin in the skin. This protects skin from sunlight and allows more time in the sun without a painful skin reaction. An implant is placed under the skin that slowly releases the medicine. Talk with your health care provider about safety information and any potential serious side effects.

Lifestyle and home remedies

If you have porphyria:

• Learn what could trigger symptoms. Talk to your health care provider about the type of porphyria you have. Learn about possible symptom triggers and how to avoid them.
• Inform your health care providers. Tell all your providers that you have porphyria. This is important because sometimes treatments, medicines, illness or surgery can trigger porphyria symptoms.
• Wear a medical alert bracelet or necklace. Have information about your condition placed on a medical alert bracelet or necklace. Always wear it.

Preparing for an appointment

If you have symptoms of porphyria, you're likely to start by seeing your primary care provider. However, because porphyria can be difficult to diagnose, you may be referred to a specialist in blood disorders (hematologist) or skin conditions (dermatologist).

Here's some information to help you get ready, and what to expect during your appointment.

What you can do

Before your appointment, make a list of:

• Any symptoms you're experiencing, including any that may seem unrelated to the reason for your appointment.
• Bring photos of any rashes to the appointment, in case you don't have a rash on the day of your appointment.
• Key personal information, including any major stresses or recent life changes. Give as much information as you can about previous symptoms and what may have triggered them.
• All medicines, vitamins, herbs or other supplements that you're taking, including doses.
• Questions to ask your health care provider.

Questions to ask may include:

• What's the most likely cause of my symptoms?
• What are other possible causes?
• What kinds of tests do I need?
• What treatments do you suggest?
• What are the alternatives to the main approach that you're suggesting?
• I have another health condition. How can I best manage these together?
• Are there any precautions or restrictions I should follow?
• Do I need genetic testing? If so, should my family members also be tested?
• Are there any brochures or other printed material that I can have? What websites do you suggest?

Feel free to ask other questions during your appointment.

What to expect from your doctor

Your health care provider is likely to ask you several questions. These may include:

• When did your symptoms start?
• Have your symptoms been constant or do they come and go?
• What, if anything, seems to make your symptoms better?
• What, if anything, seems to make your symptoms worse?
• Do any family members have similar symptoms?

Be ready to answer questions so that you can spend time on areas that are important to you.