psittacosis An infectious disease that is due to a bacterium (Chlamydia psittaci) contracted from psittacine birds, especially caged birds such as parrots, parakeets, and lovebirds. It is also seen in turkey-processing plants. C. psittaci enters the human body by inhalation of air containing dried secretions from infected birds. Signs and symptoms include fever and chills,…
psoas Two muscles of the lower back. There are two psoas muscles on each side of the back. The larger of the two is called the psoas major and the smaller the psoas minor. The psoas major originates at the spine, around the bottom of the rib cage, and runs down to the thighbone (the…
psoriasis A reddish, scaly, plaque-like rash that is often located over the surfaces of the elbows, knees, and scalp, and around or in the ears, navel, genitals, or buttocks. Approximately 10 to 15 percent of patients with psoriasis develop joint inflammation (inflammatory arthritis). Psoriasis is caused by the body making too many skin cells as…
psoriasis, guttate An uncommon type of psoriasis that is characterized by small, red-pink drops on the skin that are finer than the typical plaque-like rash of psoriasis. The condition may be triggered by an infection, often by Streptococcus bacteria. See psoriasis.
psoriasis, pustular An uncommon type of recurring psoriasis that is characterized by the appearance of pus-filled pimples and sores in clusters. Pustular psoriasis can be intensely painful, and hospitalization may be necessary.
psoriatic arthritis Joint inflammation that is associated with psoriasis. Psoriatic arthritis is a potentially destructive and deforming form of arthritis that affects approximately 10 percent of persons with psoriasis.
psyche The mind.
psychiatrist A physician who specializes in the prevention, diagnosis, and treatment of mental illness. A psychiatrist must receive additional training and serve a supervised residency in his or her specialty. He or she may also have additional training in a psychiatric specialty, such as child psychiatry or neuropsychiatry. Psychiatrists can prescribe medication, which psychologists cannot…
psychiatry The medical specialty that is concerned with the prevention, diagnosis, and treatment of mental illness.
psychogenic Caused by the mind or emotions.
psychological child abuse See child abuse.
psychologist A professional who specializes in the diagnosis and treatment of diseases of the brain, emotional disturbance, and behavior problems. Psychologists use talk therapy as treatment; a person must see a psychiatrist or another medical doctor to be treated with medication. A psychologist may have a master’s degree (MA) or doctorate (PhD) in psychology. Psychologists…