Psoriasis Glossary
Antibodies:
Special proteins, produced by the body's immune system, that
help fight and destroy viruses, bacteria, and other
foreign substances that invade the body.
Autoantibodies:
Abnormal antibodies produced against the body's own tissues.
Autoimmune disease:
A disease in which the immune system destroys or attacks a
person's own tissues.
Cytokines:
Chemical messengers in the body that help direct and regulate
response and are involved in cell-to-cell
communication.
Dermis:
The layer of skin beneath the epidermis.
Emollient:
A substance composed of fat or oil that soothes and softens the
skin.
Epidermis:
The outermost layer of skin.
Erythrodermic psoriasis:
A form of psoriasis characterized by widespread reddening and
scaling of the skin often accompanied by itching or
pain. Symptoms may be precipitated by severe sunburn, use of
oral steroids, or a drug-related rash.
Gene:
A unit of inheritance that contains the instructions, or code, that
a cell uses to make a specific product, usually a
protein. Genes are made of a substance called DNA. They
govern every body function and determine inherited traits
passed from parent to child.
Genetics:
The science of understanding how diseases, conditions, and
traits are inherited.
Guttate psoriasis:
A form of psoriasis characterized by drop-like lesions on the
trunk, limbs, and scalp. Symptoms may be triggered by
viral respiratory infections or certain bacterial (streptococcal)
infections.
Histologic examination:
The study of a tissue specimen by staining it and examining it
under a microscope.
Inflammation:
A characteristic reaction of tissues to injury or disease. It is
marked by four signs: swelling, redness, heat, and pain.
Immune response:
The reactions of the immune system to foreign substances.
Immune system:
A complex network of specialized cells and organs that work
together to defend the body against attacks by foreign
substances, such as bacteria and viruses.
Inverse psoriasis:
A form of psoriasis characterized by large, dry, smooth, vividly
red plaques in the folds of skin.
Keratolytic:
A substance that promotes the softening and peeling of the
epidermis.
Phototherapy:
Use of natural or artificial light to treat a disease.
Plaques:
Patches of thickened and reddened skin that are covered by
silvery scales.
Psoriasis:
A chronic (long-lasting) skin disease characterized by scaling
and inflammation. Scaling occurs when cells in the
outer layer of skin reproduce faster than normal and pile up on
the skin's surface. Possibly a disorder of the immune
system.
Psoriasis vulgaris:
The most common form of psoriasis, characterized by reddened
lesions covered by silvery scales.
Psoriatic arthritis:
Joint inflammation that occurs in about 10 percent of people
with psoriasis.
PUVA:
A treatment sometimes used for extensive or severe psoriasis
that combines oral or topical administration of a
medicine called psoralen with exposure to ultraviolet A (UVA)
light.
Systemic treatment:
A treatment, such as a pill, that is taken internally.
Topical agent:
A treatment, such as a cream, salve, or ointment, that is applied
to the surface of the skin.
Toxicity:
The potential of a drug or treatment to cause harmful side
effects.
T cell:
A type of white blood cell that is part of the immune system and
normally helps protect the body against infection and
disease. In psoriasis, it also can trigger inflammation and
excessive skin cell reproduction.
UVB phototherapy:
An artificial light treatment used for mild psoriasis.