Renal histomorphology in dogs with pyometra and control dogs, and long term clinical outcome with respect to signs of kidney disease.
BACKGROUND
Age-related changes in renal histomorphology are described, while the presence of glomerulonephritis in dogs with pyometra is controversial in current literature.


METHODS
Dogs with pyometra were examined retrospectively for evidence of secondary renal damage and persisting renal disease through two retrospective studies. In Study 1, light microscopic lesions of renal tissue were graded and compared in nineteen dogs with pyometra and thirteen age-matched control bitches. In Study 2, forty-one owners of dogs with pyometra were interviewed approximately 8 years after surgery for evidence of clinical signs of renal failure in order to document causes of death/euthanasia.


RESULTS
Interstitial inflammation and tubular atrophy were more pronounced in dogs with pyometra than in the control animals. Glomerular lesions classified as glomerular sclerosis were present in both groups. No unequivocal light microscopic features of glomerulonephritis were observed in bitches in any of the groups. Two bitches severely proteinuric at the time of surgery had developed end stage renal disease within 3 years. In five of the bitches polyuria persisted after surgery. Most bitches did not show signs of kidney disease at the time of death/euthanasia.


CONCLUSIONS
Tubulointerstitial inflammation was observed, but glomerular damage beyond age-related changes could not be demonstrated by light microscopy in the dogs with pyometra. However, severe proteinuria after surgery may predispose to development of renal failure.
Heiene
Reidun
R
Department of Companion Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo, Norway. reidun.heiene@veths.no
Kristiansen
Veronica
V
Teige
Jon
J
Jansen
Johan Høgset
JH
D000375:Aging; D000818:Animals; D016022:Case-Control Studies; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D005260:Female; D007668:Kidney / Q000473:pathology*; D007674:Kidney Diseases / Q000473:pathology / Q000662:veterinary*; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014591:Uterine Diseases / Q000473:pathology / Q000662:veterinary*