Porphyria is a group of disorders that can cause nerve or skin problems.
A porphyria that affects the skin is called cutaneous porphyria. A porphyria that affects the nervous system is called acute porphyria.
The most common type of porphyria is porphyria cutanea tarda (PCT), which affects the skin. PCT is also the most treatable.
No known cure exists for any type of porphyria.
Symptoms of Acute Porphyria
The symptoms of acute porphyria can develop quickly and last for days or weeks. A salt imbalance sometimes accompanies an episode of this type of porphyria. The imbalance can contribute to some of these symptoms:
Long-term complications in some patients have included:
Symptoms of Cutaneous Porphyria
Symptoms of cutaneous porphyria occur when the skin is exposed to sunlight. The most commonly affected areas include the back of the:
The symptoms include:
- Swelling of the skin
- Increased hair growth
- Darkening and thickening of the skin
Causes of Porphyria
Each type of porphyria has the same root cause -- a problem in the production of heme. Heme is a component of hemoglobin. That's a protein in red blood cells that carries oxygen from the lungs to the rest of the body.
Heme contains iron and gives blood its red color. The production of heme takes place in the liver and bone marrow and involves many different enzymes. A shortage of any of those enzymes can create an excess buildup of certain chemical compounds involved in producing heme. The specific type of porphyria is determined by which enzyme is lacking.
Most types of porphyria are inherited. About half of them occur when one altered gene is passed from just one parent. The risk of developing a porphyria or passing it to your children depends on the specific type.
Porphyria cutanea tarda, on the other hand, is often an acquired disease. Although the enzyme deficiency that causes PCT can be inherited, most people who inherit it never develop symptoms. Instead, the disease becomes active when the deficiency is triggered by certain conditions or lifestyle choices. These include:
Episodes of acute porphyria, which very rarely occur before puberty, can be triggered by some drugs. These include:
Other potential triggers include:
- Drinking alcohol
- Menstrual hormones
- Sun exposure