Pathological Changes of Urinary System in a Dog with Urolithiasis and Renal Papillary Necrosis

Authors

  • Tuncer Kutlu Department of Pathology, Faculty of Veterinary Medicine, Ankara University (AU), Ankara, Turkey.
  • Gözde Yücel-Tenekeci Department of Pathology, Faculty of Veterinary Medicine, Ankara University (AU), Ankara, Turkey.
  • Mert Pekcan Department of Pathology, Faculty of Veterinary Medicine, Ankara University (AU), Ankara, Turkey.
  • Emir Yengy Kuler Department of Pathology, Faculty of Veterinary Medicine, Ankara University (AU), Ankara, Turkey.
  • Osman Kutsal Department of Pathology, Faculty of Veterinary Medicine, Ankara University (AU), Ankara, Turkey.

DOI:

https://doi.org/10.22456/1679-9216.95450

Abstract

Background: Urolithiasis is one of the important lower urinary tract diseases in dogs. Uroliths develop when urine becomes "supersaturated”. Struvite urolithiasis in dogs is formed when urine saturated with magnesium, ammonium and phosphate. Renal papillary necrosis is a form of nephropathy involving the necrosis of the renal papilla. The aim of this case is the evaluation of histopathological changes in kidney and urinary bladder caused by urolithiasis with sitruvite, a pathology commonly seen in dogs. Renal papillary necrosis that encountered in the case was evaluated histopathologically. We intend to discuss the relationship between urolithiasis and renal papillary necrosis.

Case: The material of the case was a 7.5 year-old Rottweiler female dog that had been operated for the urolithiasis treatment and died after surgery. The animal sent to pathology department was necropsied and evaluated histopathologically. Also the uroliths removed during the surgery were sent for analysis postoperatively. Qualitative composition of uroliths was determined by a series of chemical analyses in Department of Biochemistry. X-ray diffraction was performed as well in General Directorate of Mineral Research and Exploration in the objective of result verification.  Macroscopically, 30 pieces uroliths with varying size from 1 mm to 3 cm were seen in urinary bladder. They were 110 g in weight with smooth surface and round and/or ovoid shapes.  After necropsy, specimens from kidney and urinary bladder were fixed in 10% neutral buffered formalin, embedded in paraffin wax, cut at 5 μm, and stained with hematoxylin and eosin (HE).  Bladder wall thickening and hemorrhage on mucosa were noticed. Kidneys had roughened surface with the capsule being difficult to peel off. Also, renal papillary necrosis, reddish in color was observed in papilla of the right kidney. Microscopically, crystal formations were observed proximal tubule lumens of kidneys. Interstitial nephritis in cortex and medulla had been noticed in both kidneys. Interstitial nephritis has been noticed in both kidneys. Hemorrhagic necrotic area demarcated by connective tissue was encountered in medulla of the right kidney. In the lamina propria of urinary bladder hemorrhage were noted. Desquamation and degeneration of lamina epithelialis and wide hemorrhage area in lamina propria were noted in urinary bladder. Results obtained from biochemical analysis were verified with x-ray diffraction method, uroliths were determined as magnesium ammonium phosphate (struvite).

Discussion: Renal papillary necrosis is a form of nephropathy involving the necrosis of the renal papilla, caused by ischemia of the inner medulla of the kidney. According to the first report of renal papillary necrosis, symmetrical soft calyceal concretions and their appearances are typical lesions for diagnosis of renal papillary necrosis. The presence of crystals in the tubule lumen and the formation of struvite stone (which has the same chemical composition with calyceal concretions) established a distinct relationship between urolithiasis and renal papillary necrosis. This case showed that struvite stones can reach large volumes in urinary bladder, and caused bladder wall thickness and hemorrhages. Also, the lower urinary tract obstruction or urolithiasis should be remembered in the renal papillary necrosis together with the risk of hydronephrosis.                 

Downloads

Download data is not yet available.

References

Breshears M.A. & Confer A.W. 2007. The urinary system. In: Zachary J.F. (Ed). Pathologic Basis of Veterinary. 6th edn. St. Louis: Saunders, pp.617-661.

Brix A.E. 2002. Renal papillary necrosis. Toxicologic Pathology. 30: 672-674

Chew D.J., Dibartola S.P. & Schenck P. 2011. Canine and Feline Nephrology and Urology. 2nd edn. St. Louis: Elsevier. pp.275-277.

Davies P.J. 1999. Beethoven’s nephropathy and death: discussion paper. Journal of the Royal Society of Medicine. 86: 159-161.

Eknoyan C., Qunibi W.Y., Grissom R.T., Tuma S.N. & Ayus J.C. 1982. Renal papillary necrosis: an update. Medicine. 61: 55-73.

Geller S.A. & Campos F.P.F. 2013. Renal papillary necrosis. Autopsy Case Reports. 3: 69-71.

Hoxha Z. & Rapti D. 2017. Urolithiasis in dogs. Albanian Journal of Agricultural Sciences. (Special edition): 637-640.

Jung D.C., Kim S.H. & Jung S.I. 2006. Renal papillary necrosis: Review and comparison of findings at Multi–Detector Row CT and intravenous urography. Radiographics. 26: 1827-1836.

Nerli R., Jali M., Kumar Guntaka A., Patne P., Patil S. & Hiremath M.B. 2015. Type 2 diabetes mellitus and renal stones. Advanced Biomedical Research. 4: 180.

Okafor C.C., Pearl D.L. & Lefebvre S.L. 2013. Risk factors associated with struvite urolithiasis in dogs evaluated at general care veterinary hospitals in the United States. Journal of the American Veterinary Medical Association. 243: 1737-1745.

Palma D., Langstone C., Gisselman K. & McCue J. 2013. Canine struvite urolithiasis. Compendium: Continuing Education for Veterinarians. 35: E1.

Seaman R. & Bartges J. 2001. Canine struvite urolithiasis. Journal of Exotic Pet Medicine. 23(5): 407-419.

Published

2019-01-01

How to Cite

Kutlu, T., Yücel-Tenekeci, G., Pekcan, M., Yengy Kuler, E., & Kutsal, O. (2019). Pathological Changes of Urinary System in a Dog with Urolithiasis and Renal Papillary Necrosis. Acta Scientiae Veterinariae, 47. https://doi.org/10.22456/1679-9216.95450

Most read articles by the same author(s)