Porphyria

 

Alternative Names

Acute intermittent porphyria; Hereditary coproporphyria; Congenital erythropoietic porphyria; Erythropoietic protoporphyria

Definition

Porphyrias are a group of rare disorders passed down through families. An important part of hemoglobin, called heme, is not made properly. Heme is also found in myoglobin, a protein found in certain muscles.

Causes

Normally, the body makes heme in a multi-step process. Porphyrins are made during several steps of this process. Patients with porphyria are lacking certain enzymes needed for this process. This causes abnormal amounts of porphyrins or related chemicals to build up in the body.

There are many different forms of porphyria. The most common type is porphyria cutanea tarda (PCT).

Drugs, infection, alcohol, and hormones such as estrogen may trigger attacks of certain types of porphyria.

Symptoms

Porphyrias involve three major symptoms:

  • Abdominal pain or cramping (only in some forms of the disease)
  • Sensitivity to light that can cause rashes, blistering, and scarring of the skin (photodermatitis)
  • Problems with the nervous system and muscles (seizures, mental disturbances, nerve damage)

Attacks can occur suddenly. They often start with severe abdominal pain followed by vomiting and constipation. Being out in the sun can cause pain, sensations of heat, blistering, and skin redness and swelling. Blisters heal slowly, often with scarring or skin color changes. The scarring may be disfiguring. Urine may turn red or brown after an attack.

Other symptoms may include:

  • Muscle pain
  • Muscle weakness or paralysis
  • Numbness or tingling
  • Pain in the arms or legs
  • Pain in the back
  • Personality changes

Attacks can sometimes be life threatening, producing:

  • Low blood pressure
  • Severe electrolyte imbalances
  • Shock

Exams and Tests

Your doctor will perform a physical exam, which includes listening to your heart. You may have a fast heart rate (tachycardia). The doctor may find that your deep tendon reflexes (knee jerks or others) do not work properly.

Blood and urine tests may reveal kidney problems or other problems. Special tests can measure porphyrins in the blood.

Some of the other tests that may be done include:

Treatment

Some of the medicines used to treat a sudden (acute) attack of porphyria may include:

  • Hematin given through a vein (intravenously)
  • Pain medication
  • Propranolol to control the heartbeat
  • Sedatives to help you feel sleepy and less anxious

Other treatments may include:

  • Beta-carotene supplements
  • Chloroquine
  • Fluids and glucose to boost carbohydrate levels, which helps limit the production of porphyrins
  • Removal of blood (phlebotomy)

Depending on the type of porphyria you have, your doctor may tell you to:

  • Avoid all alcohol
  • Avoid drugs that may trigger an attack
  • Avoid injuring the skin
  • Avoid sunlight as much as possible and use sunscreen when outside
  • Eat a high-carbohydrate diet

Outlook (Prognosis)

Porphyrias are life-long diseases with symptoms that come and go. Some forms of the disease cause more symptoms than others. Getting proper treatment and staying away from triggers can help lengthen the time between attacks.

Possible Complications

When to Contact a Medical Professional

Get medical help as soon as you have signs of an acute attack. Talk to your doctor about your risk for this condition if you have a long history of undiagnosed abdominal pain, muscle and nerve problems, and sensitivity to sunlight.

Prevention

Genetic counseling may benefit people who want to have children and who have a family history of any type of porphyria.

References

Anderson K. The porphyrias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 217.

Fuller SJ, Wiley JS. Heme biosynthesis and its disorders. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, Weitz JI, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Saunders Elsevier; 2012:chap 36.

Review Date: 3/3/2013
Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.