Chronic Cystitis and Pyelonephritis in a Boxer

History: A 10 year old female spayed Boxer had an acute onset of Respiratory distress and a long history of mildly elevated BUN and Creatinine that spiked at the time of presentation.  Radiographs of the chest showed diffuse miliary radio-opaques lesions.
Gross Findings:
Kidneys: Hydronephrosis and pyelonephritis, bilateral.

There was clear fluid with some white flocculent material [...]