Psoriasis Glossary

Autoimmune disease. A disease caused by a malfunction of the body's immune system, the natural defense system against infections. The immune system mistakenly attacks the body's own cells -- which can cause an autoimmune disease like psoriasis.

Biologic drugs / therapies. Medications made from living organisms to treat moderate to severe psoriasis. Biologic drugs work by targeting the harmful attacks from the immune system that cause psoriasis symptoms. Biologic drugs include Amevive, Enbrel, Humira, Raptiva, and Remicade.

Guttate psoriasis. A less common type of psoriasis, primarily found on children and young adults. The skin spots are much smaller and not as thick as those of plaque psoriasis. They usually appear on the trunk, arms, and legs. They often occur suddenly with a cold or other respiratory infection, or after an episode of tonsillitis or a strep infection.

Immune system. The body's natural defense system which helps fight infections. When the immune system mistakenly attacks the body's own cells, it is called an autoimmune response -- which can trigger an autoimmune disease like psoriasis.

KOH Test. A test used in diagnosing fungal infections of the skin, nails, or hair. The KOH skin test can determine whether a fungus is causing the skin condition. The chemical compound potassium chloride (KOH) is used in the skin test.

Phototherapy. A treatment for psoriasis that involves brief exposures to ultraviolet light -- ultraviolet B (UVB) or A (UVA).

Psoralen and UVA light therapy (PUVA). A treatment for psoriasis that involves taking psoralen medication before a brief exposure to ultraviolet A (UVA) light.

Plaque. Patches of scaling skin that cover sores, the symptoms of psoriasis. Plaque patches usually appear on elbows, knees, and trunk.

Psoriatic arthritis. A form of arthritis that may develop in someone with psoriasis. The fingers and toes are most often affected.

Pustular psoriasis: A type of recurring psoriasis characterized by the appearance of pus-filed pimples and sores in clusters. It can be intensely painful, and hospitalization may be required.

Topical medications. Ointments, creams, and solutions that are applied to skin. Topical medications used for psoriasis include: Vitamin D, corticosteroids, retinoids, anthralin, and coal tar.