hydropyonephrosis

[hī′drō-pī′ō-nə-frōsĭs]
n.
  1. The accumulation of purulent urine in the pelvis and calices of the kidneys, usually the result of bacterial infection following obstruction of the ureter.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.