Porphyria is the term used to describe a group of rare diseases characterised by an overproduction of substances called porphyrins, which is caused by a metabolic defect that is usually inherited genetically.
The body requires porphyrins for the production of haem (a constituent of haemoglobin), which functions to carry oxygen from the lungs to the rest of the body. In porphyria, there is a deficiency in the enzymes required to metabolise the porphyrins; the resulting overproduction manifests in the skin or neurological system.
While porphyria’s causes are mainly genetic, one type, porphyria cutanea tarda, is acquired as a result of certain forms of liver dysfunction, and cannot be inherited.
The two main types of porphyria are identified as:
- Cutaneous porphyria, which affects the skin
- Acute porphyria, which affects the nervous system.
What are its symptoms?
Symptoms of acute porphyria include the following:
- Abdominal pain
- Chest pain
- Increase in heart rate and blood pressure
- Muscle weakness
- Arm, leg and back pain
- Cramping
- Vomiting and constipation
- Changes in personality
- Changes in mental state, including paranoia, hallucinations
- Confusion and/or agitation
- Seizures
- Red or brown urine
The long-term effects of porphyria may include chronic pain, depression, and kidney and liver damage. These symptoms appear in the forms of flare-ups or attacks lasting from one to two weeks. Onset is often quick and can be life-threatening.
The main symptom of cutaneous porphyria is a sensitivity to light that affects the hands, forearms, face, ears and neck, and results in:
- Blisters and rash (these may take weeks to heal or clear up)
- Skin swelling
- Pain
- Thickening and darkening of the skin
- Increased hair growth
While porphyria symptoms may overlap with other conditions, seek medical attention immediately if you experience severe abdominal, chest and/or neck pain accompanied by constipation or diarrhoea and vomiting; or extreme sensitivity to light that causes a burning pain, swelling and/or blistering of the skin.
How is it diagnosed?
A porphyria diagnosis can be made by performing tests on blood, urine or stool samples. Multiple tests may be required to establish the particular type of porphyria present.
What are your treatment options?
Porphyria treatment depends on the type and severity of the symptoms. A person suffering from an acute porphyria attack will often require hospitalisation, where treatment will be given for pain, nausea and other symptoms. Glucose or haemin injections may also be administered. Nerve damage and related muscle weakness may require up to several months to repair.
For cutaneous porphyria attacks, treatment may include regular blood removal or a phlebotomy to reduce the amount of iron in the liver; low doses of the antimalarial drug chloroquine; and cool compresses applied topically.
Can it be prevented?
Most kinds of porphyria are inherited and can therefore not be prevented. Risks vary depending on the type, but about half can occur if one altered gene is passed from one parent.
Episodes of acute porphyria may be triggered by the use of barbiturates, tranquilizers and sedatives. Cutaneous porphyria is mostly an acquired disease, which can become active when triggered by certain conditions, such as hepatitis C and HIV/AIDS, or lifestyle issues, including excessive intake of iron, alcohol consumption and smoking. Other potential triggers also include fasting, menstrual hormones and stress.
For more info
For more information and support groups, visit:
The joint University of Cape Town and University of KwaZulu/Natal information site on porphyria