Porphyria (poor-FEAR-e-uh) refers to a group of disorders that result from a buildup of natural chemicals that produce porphyrin in your body. Porphyrins are essential for the function of hemoglobin — a protein in your red blood cells that links to porphyrin, binds iron, and carries oxygen to your organs and tissue. High levels of porphyrins can cause significant problems.
Porphyria mainly affects your nervous system, skin and other organs. The signs and symptoms of porphyria can vary, depending on the specific type and severity. Porphyria is usually inherited — one or both parents pass along an abnormal gene to their child. But in some types of porphyria, environmental factors may trigger the development of symptoms.
Treatment depends on the type of porphyria you have. Although porphyria usually can't be cured, certain lifestyle changes may help you manage it.
There are two general categories of porphyria — acute, which mainly affects the nervous system, and cutaneous, which mainly affects the skin. Some types of porphyria have both nervous system symptoms and skin symptoms, and others have mainly one or the other.
Acute porphyrias include forms of the disease that typically cause nervous system symptoms, which appear quickly and can be life-threatening. Acute porphyria attacks are rare before puberty and after menopause in women. Symptoms may last one to two weeks and usually improve slowly after the attack.
Possible signs and symptoms of acute porphyria include:
- Severe abdominal pain
- Swelling of the abdomen (abdominal distention)
- Pain in your chest, legs or back
- Constipation or diarrhea
- Heartbeat you can feel (palpitations)
- High blood pressure
- Anxiety or restlessness
- Mental changes, such as confusion, hallucinations, disorientation or paranoia
- Breathing problems
- Muscle pain, tingling, numbness, weakness or paralysis
- Red or brown urine
Cutaneous porphyrias include forms of the disease that cause skin symptoms as a result of oversensitivity to sunlight, but these forms don't usually affect your nervous system. Attacks may last for several days. With some forms, signs and symptoms may start during infancy or childhood.
As a result of sun exposure, you may experience:
- Sensitivity to the sun and sometimes artificial light, causing burning pain
- Sudden painful skin redness (erythema) and swelling (edema)
- Blisters that take weeks to heal
- Fragile skin
- Scars or skin color changes from healing blisters
- Increased hair growth
- Red or brown urine
When to see a doctor
Many signs and symptoms of porphyria are similar to those of other, more common conditions. This can make it difficult to know if you're having an attack of porphyria. Any of the following symptoms should prompt you to seek immediate medical attention:
- Severe abdominal pain, but sometimes pain in your chest, legs or back, accompanied by constipation, vomiting and sometimes diarrhea
- Sensitivity to the sun and sometimes artificial light, causing burning pain and sudden painful skin blistering, redness (erythema) and swelling (edema)
- Red or brown urine
Porphyria is most often an inherited mutation in one of the genes involved in heme production, although environmental factors can trigger symptoms in some cases.
Heme is a major component of hemoglobin, the protein in red blood cells that carries oxygen from your lungs to all parts of your body. Heme also plays a role in breaking down chemicals so they can be removed from your body. Heme is made mainly in the bone marrow and liver through the production of porphyrin and linkage with iron.
Eight different enzymes add and convert natural, smaller building blocks into porphyrin, which becomes heme with the addition of iron. Deficiency of a specific enzyme that's involved in the body's process for making heme can result in the buildup of porphyrins, causing symptoms. Each type of porphyria is due to the deficiency of a different enzyme.
Most forms of porphyria are inherited. Porphyria can occur if you inherit:
- A defective gene from one of your parents (autosomal dominant pattern)
- Defective genes from both parents (autosomal recessive pattern)
Just because you have inherited a gene or genes that can cause porphyria doesn't mean that you'll have signs and symptoms. You might have what's called latent porphyria, and never have symptoms. This is the case for most carriers of the abnormal genes.
In addition to genetic risks, environmental factors may trigger the development of signs and symptoms in some types of porphyria. When exposed to the trigger, your body's demand for heme production increases. This overwhelms the deficient enzyme, setting in motion a process that causes signs and symptoms. Examples of triggers include:
- Certain drugs (barbiturates or sulfonamide antibiotics or, less often, birth control pills, or some drugs that affect the mind or behavior, known as psychoactive drugs)
- Dieting or fasting
- Physical stress, such as infections or other illnesses
- Liver disease
- Emotional stress
- Alcohol use
- Menstrual hormones
- Sun exposure
- Excess iron in your body
Possible complications of porphyria include:
- Dehydration. Vomiting due to an attack of acute porphyria can lead to dehydration, which may require that you receive fluids through a vein (intravenously).
- Breathing difficulties. Acute porphyrias can cause muscle weakness and paralysis, which can cause breathing problems. If left untreated, they can also lead to respiratory failure.
- Low sodium in your blood. Called hyponatremia, this is usually linked to problems with sodium and water handling in your body.
- High blood pressure. Porphyrin buildup can damage your kidneys and may result in high blood pressure (hypertension).
- Chronic kidney failure. Porphyrin buildup may cause your kidneys to gradually lose their ability to function.
- Liver damage. Some forms of porphyria cause excessive porphyrins in your liver, which may lead to severe liver damage that can eventually require a liver transplant.
- Permanent skin damage. When your skin heals after cutaneous porphyria, it may have an abnormal appearance and coloring. Scars may remain on your skin as well, and lasting skin problems may cause your hair to fall out.
If you have signs and 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 doctor who specializes in blood disorders (hematologist).
Here's some information to help you get ready, and what to expect from your doctor.
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
- Key personal information, including any major stresses or recent life changes
- All medications, vitamins or other supplements that you're taking, including dosages
Preparing a list of questions before your appointment will help you make the most of your time. For porphyria, some basic questions to ask your doctor include:
- What's the most likely cause of my symptoms?
- What are other possible causes?
- What kinds of tests do I need? Do I need genetic testing?
- How severe is my condition?
- What's the best course of action?
- What are the alternatives to the primary approach that you're suggesting?
- I have another health condition. How can I best manage these together?
- Are there any dietary restrictions I need to follow?
- What precautions do I need to take when spending time outdoors?
- Do I need to be concerned about taking medications in the future?
- Are there any brochures or other printed material that I can have? What websites do you recommend?
- Should my family members be screened?
- Will I need a medical alert bracelet?
Don't hesitate to ask any other questions during your appointment.
What to expect from your doctor
Your doctor is likely to ask you a number of questions, such as:
- When did you first begin experiencing symptoms?
- Have your symptoms been continuous or occasional?
- How severe are your symptoms?
- What, if anything, seems to improve your symptoms?
- What, if anything, appears to worsen your symptoms?
- Do any family members have similar symptoms?
Many signs and symptoms of porphyria are similar to those of other more common diseases. Also, because porphyria is rare, it can be more difficult to diagnosis. Lab tests are required to make a definitive diagnosis of porphyria and to determine which form of the disease you have.
If your doctor suspects porphyria, he or she may recommend these tests:
- Urine test. If you have a form of acute porphyria, a urine test may reveal elevated levels of two substances: porphobilinogen (por-foe-bih-LIN-uh-jen) and delta-aminolevulinic (uh-me-no-lev-yoo-LIN-ik) acids, as well as other porphyrins.
- Blood test. If you have a form of cutaneous porphyria, a blood test may show an elevation in the level of porphyrins in your blood plasma.
- Stool sample test. Analysis of a stool sample may reveal elevated levels of some porphyrins that may not be detected in urine samples. This test may help your doctor determine your specific type of porphyria.
More tests may be needed to confirm the type of porphyria you have. Genetic testing may be suggested in the family of a person with porphyria.
Treatment depends on the type of porphyria you have and is directed at relieving symptoms.
Treatment of acute porphyrias focuses on providing rapid treatment of symptoms and preventing complications. This may require hospitalization in severe cases. Treatment may include:
- Stopping medications that may have triggered symptoms
- Medication to control pain, nausea and vomiting
- Prompt treatment of infections or other illness that may have caused symptoms
- Intravenous sugar (glucose) or sugar taken by mouth, if able, to maintain an adequate intake of carbohydrates
- Intravenous fluids to combat dehydration
- Injections of hemin, a medication that is a form of heme, to limit the body's production of porphyrin
Treatment of cutaneous porphyrias focuses on reducing exposure to sunlight and the amount of porphyrins in your body to help eliminate your symptoms. This may include:
- Drawing blood (phlebotomy). Drawing a certain amount of blood from one of your veins reduces the iron in your body, which decreases porphyrins. You may need to have a phlebotomy repeated at regular intervals before cutaneous porphyria goes into remission.
- Medication. Drugs used to treat malaria — hydroxychloroquine (Plaquenil) or, less often, chloroquine (Aralen) — can absorb excess porphyrins and help your body get rid of them more quickly than usual. These medications are generally used only in people who can't tolerate a phlebotomy.
- Beta carotene. Long-term treatment of cutaneous porphyrias may include daily doses of prescription beta carotene. Beta carotene may increase your skin's tolerance to sunlight. Your doctor can tell you what kind of beta carotene will work best for porphyria photosensitivity.
- Reducing or eliminating triggers. Triggers, such as certain medications or too much sunlight, which activated the disease, should be reduced or removed if possible, with guidance from your doctor.
- Vitamin D. Supplements may be recommended to replace vitamin D deficiency caused by avoidance of sunlight.
If you have porphyria:
- Learn what could trigger symptoms. Talk to your doctor about the type of porphyria you have and become familiar with possible symptom triggers and ways to avoid them.
- Inform your health care providers. Tell all your health care providers that you have porphyria. This is particularly important because sometimes treatments, medications or surgery can trigger porphyria symptoms.
- Wear a medical alert bracelet or necklace. Have information about your condition inscribed on a medical alert bracelet or necklace, and always wear it.
Although there's no way to prevent porphyria, if you have the disease, these steps may help prevent symptoms:
- Avoid medications known to trigger acute attacks. Ask your doctor for a list of safe and unsafe drugs.
- Don't use alcohol or illegal drugs.
- Avoid fasting and dieting that involves severe calorie restriction.
- Don't smoke.
- Minimize sun exposure. When you're outdoors, wear protective clothing and use a broad-spectrum sunscreen with a high sun protection factor (SPF).
- Treat infections and other illnesses promptly.
- Take steps to reduce emotional stress.
Because porphyria is an inherited disorder, your siblings and other family members may want to consider genetic testing to determine if they have the disease.