What causes Plaque Psoriasis?

No one individual cause has been found for psoriasis, but it is known that genetics (heredity) and environmental factors, as well as the immune system, all play a role. It is estimated that a person has a 30% chance of developing psoriasis if both their parents are affected. Researchers believe that a trigger is needed in order to develop psoriasis. These triggers can include some infections, injuries to the skin, some medications, stress and sunburn.

What is known about psoriasis is the role of the immune system. When the immune system is working properly, it protects us against things like bacteria, viruses and fungi. It also helps prevent cancer and other diseases. But an over stimulation of the immune system can result in immune cells attacking healthy cells in the body. In plaque psoriasis, the immune system sends faulty signals to the outer layers of the skin, resulting in rapid overgrowth of skin cells and the appearance of scaly patches. This immune system malfunction is why psoriasis is referred to as an autoimmune disease.