Frequently Asked Questions
Acute Hepatic Porphyrias
The Acute Hepatic Porphyrias (AHP) are porphyrias where the main effects of the enzyme defects are in the liver (hepatic) and include:
For in-depth information on living with your porphyria, visit the United Porphyrias Association website.
Individuals with a disease-causing change in one of the acute porphyria genes without symptoms have "latent" acute porphyria. However, this does not mean that they will never have symptoms. Exposure to certain environmental factors, such as medications, can greatly influence whether an individual with a porphyria-causing gene change has symptoms. This is why it is important that all family members of individuals diagnosed with acute porphyria be tested, whether they have symptoms or not, and that all individuals who have a confirmed diagnosis of acute porphyria be educated about and follow the recommended precautionary and preventive measures.
Yes! The diagnosis of acute porphyria is always an important piece of medical information, even when there are no symptoms. It may, for example, influence the choice of medications to treat other conditions, the choice of anesthesia for surgery, or dietary recommendations.
Surgery and pregnancy may increase the risk of an acute porphyria attack. This risk can be greatly reduced if certain precautions are taken, including the type of anesthesia used in surgeries. The surgeon and anesthesiologist should consult a porphyria expert prior to hospitalization for surgery. Such consultation may also be helpful during pregnancy. Attacks of acute porphyria can occur during pregnancy. Treatment of acute attacks during pregnancy is also possible.
For information about safe and unsafe drugs in the acute porphyrias, it is best to consult the European Porphyria Network. The database contains expert assessments of the potential of drugs to provoke attacks of acute porphyria (AIP, VP, HCP & ADP) based on the available evidence. However, this evidence is not always complete, which may lead to some degree of uncertainty. The information in this database is meant as guidance to health care professionals. It must be made clear that the prescription of drugs to a patient with acute porphyria is entirely at the risk of the physician in charge.
Since most commonly used drugs have not been tested, they should be avoided if at all possible. If a question regarding drug safety arises, a physician or medical center specializing in porphyria should be contacted.
Yes, males and females are equally at risk for having acute porphyria. Exposure to certain environmental factors, such as drugs, chemicals, and diet, greatly influence whether an individual - men and women - with a change in a porphyria-causing gene has symptoms and the severity of symptoms. However, one of the environmental factors is hormones, and, therefore, acute attacks are more common in women. Women may experience cyclical acute attacks associated with their menstrual cycle, starting in puberty. Such attacks in women may occur after ovulation and during the last part of the menstrual cycle when progesterone levels are high.
People with an acute porphyria should have a healthy balanced diet. Fasting for long periods of time and dieting should be avoided.
Thinking and memory can be affected when someone is having an acute attack. Someone with acute porphyria may also experience some neurological effects, including confusion, convulsions, muscle weakness, and, rarely, paralysis, due to effects on the nervous system from an acute attack. The effects of acute porphyria on long term thinking and memory are not known.
An acute attack can be brought on by certain drugs, hormones in women, environmental factors including chemicals of various types, nutrition including fasting and low carbohydrate diets, alcoholic beverages, medical and physical stress, and physical fatigue. Many times, the trigger of an acute attack is unknown.
Flu shots are okay to take for people with acute porphyria, and can be taken safely. Any immunizations also appear to be okay. In fact, since other illnesses can bring on an acute attack, remaining healthy is one of the most important ways to prevent acute attacks.
There has been no information to date to suggest that CAT scans with or without contrast agents should not be performed on an individual with acute porphyria.
Drugs on the “unsafe” list are those drugs that should be avoided by individuals with an acute porphyria because they have been found to provoke an acute attack in some individuals. If a drug prescribed for an individual diagnosed with an acute porphyria is on the “unsafe” list, the prescribing physician should check the Drug Database for a safe alternative.
No drug should be withheld if it is judged essential for optimum treatment of a life-threatening condition (e.g. chemotherapy for cancer). The risk versus the benefit should be assessed and discussed with the patient. For help with this assessment you may wish to contact a Porphyria expert. It may be recommended that a person undergo biochemical monitoring (i.e., ALA and PBG levels) in the early stages of treatment. It must also be noted that response to drugs in people with an acute porphyria is extremely variable and individuals may be encountered who have used an unsafe drug without adverse effect.
Donation of blood might not be harmful to you if you are in good health and have not had a recent attack. Your blood would also not be harmful to a recipient. However, a blood bank might have a policy of not taking blood from anyone with a chronic condition, just to be on the safe side.
Acute porphyrias are liver disorders, so your liver should not be donated, because the recipient would be likely to develop acute porphyria. Because acute porphyrias can damage the kidneys, you should probably not be a living kidney donor, and losing a kidney would reduce your reserve kidney function. A transplant program might have a policy of not transplanting certain organs from anyone with a chronic condition, just to be on the safe side. But transplanting some tissues, such as skin and cornea, should not be a problem.
This may be as short as a few days, but is highly variable. Multiple triggers may be present, so the timing of symptoms cannot be predicted.
Attack symptoms are nonspecific and can be mimicked by many other medical conditions. If an individual has been diagnosed already as having acute porphyria, the diagnosis of an acute attack is based on the symptoms and physician judgement. The levels of porphyrin precursors (porphobilinogen [PBG] and aminolevulinic acid [ALA]) are not determining factors because these often remain high between attacks. However, levels of ALA and PBG generally do spike during acute attacks.
If you are vomiting, have severe pain, seizures, or other neurological symptoms, it is often best to go the ER.
Yes. A seizure can be due to effects of acute porphyria on the brain, or be a consequence of decreased sodium in the bloodstream, which is a complication of the attack. Seizures generally indicate that the attack is severe and requires medical attention as soon as possible.
Attacks cause increases in the heart rate and blood pressure, due to effects on the autonomic nervous system, and these will generally return to normal with treatment of the attack. People with acute porphyria may develop chronic hypertension, which needs to be managed in the usual manner.
Your doctor can advise on managing your diabetes using pills and/or insulin. A dietitian is also helpful for designing a diet with the proper amounts of carbohydrate and fat.
Premenstrual attacks are likely due at least in part to the high levels of progesterone that occur during the second half of the cycle. If these are frequent, and no other factors are contributing, such attacks may be prevented using a GnRH analogue (e.g. Lupron) or Givlaari. You should discuss these treatment options with your doctor and a porphyria expert. Removal of the ovaries is not considered unless there are other medical indications and the patient is interested in permanent sterilization.
Yes. Other conditions that decrease food intake or cause fever and metabolic stress can trigger an attack.
This is not indicated if a healthy diet containing all required nutrients is maintained. A multivitamin tablet containing the daily requirements is not harmful, however.
It may be best to consult a dietitian to be sure you get an adequate amount of all required nutrients. A vegetarian diet generally will contain adequate amounts of carbohydrates and fiber, but may be low in protein, some vitamins and minerals such as iron and zinc.
Checking levels of urine porphobilinogen and aminolevulinic acid at least yearly is advisable to have some idea how active your acute porphyria is.