Dictionary

PWS Prader-Willi syndrome.

PXE Pseudoxanthoma elasticum.

pyarthrosis See arthritis, septic.

pycnodysostosis An inherited disorder of bone that causes short stature and abnormally dense brittle bones. Pycnodysostosis can be due to a defect in the enzyme cathepsin K. Sometimes spelled pyknodysostosis. The French artist Toulouse-Lautrec is thought to have had this disease. No specific treatment is available.

pyelo See pyelonephritis.

pyelogram An X-ray study of the kidneys, especially showing the pelvis (urine-collecting basin), and the ureter.

pyelonephritis Bacterial infection of the kidneys. Pyelonephritis can be acute or chronic, and it is most often due to the ascent of bacteria from the bladder up the ureters to infect the kidneys. Symptoms include flank (side) pain, fever, shaking chills, sometimes foul-smelling urine, frequent and urgent need to urinate, and general malaise. Tenderness is…

pyloric stenosis Narrowing (stenosis) of the outlet of the stomach so that food cannot pass easily from it into the duodenum. Pyloric stenosis results in feeding problems and projectile vomiting in infants. The obstruction can be corrected with a relatively simple surgical procedure.

pylorus The outlet of the stomach.

pyoderma gangrenosum An ulcerating condition of skin that results in heaped borders with a typical appearance. Pyoderma gangrenosum appears to be mediated by the immune system, but the exact cause is unknown. The lesion usually begins as a soft nodule on the skin that then ulcerates. The ulcer enlarges, and the skin at the edge…

pyogenic arthritis Purulent arthritis with pus as a result of infection within the joint. See arthritis, septic.

pyrexia See fever.