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. 2025 Apr;66(4):248-257.
doi: 10.1111/jsap.13821. Epub 2025 Jan 13.

Retrospective analysis of the incidence and clinicopathological findings associated with ammonium urate urolithiasis in dogs with congenital portosystemic shunts: 363 cases (2010-2023)

M Walton-Clark  1 , V Travail  2 , T Sparks  3 , A Eiras-Diaz  4 , A Davenport  5 , A Holmes  6 , A Kent  7 , C Prior  8 , C Stilwell Breakspear  9 , C Dye  5 , C Good  10 , C Motta  2 , F Valls Sanchez  11 , F Pilati  9 , G McLauchlan  12 , G Ruiz  13 , I Brás  4 , J Scott  6 , K Clarke  14 , K Peak  15 , L Goonan  15 , M Ots  1 , M Rossell Garcia  10 , N Lau  14 , N Mansbridge  11 , P Garcia Dominguez  15 , S Conway  16 , S Keyte  17 , T Chapman  2 , T Conley  12 , V Black  16 , V Coates  17 , A DiBella  2
Affiliations

Retrospective analysis of the incidence and clinicopathological findings associated with ammonium urate urolithiasis in dogs with congenital portosystemic shunts: 363 cases (2010-2023)

M Walton-Clark et al. J Small Anim Pract. 2025 Apr.

Abstract

Objectives: To assess the incidence and clinical findings associated with the presence of ammonium urate urolithiasis in dogs with congenital portosystemic shunts.

Materials and methods: A retrospective review of dogs diagnosed with extrahepatic portosystemic shunts or intrahepatic portosystemic shunts in 15 referral hospitals between 2010 and 2023. Data including signalment, clinical signs, physical examination findings and clinicopathologic test results at the time of the diagnosis were collected, and the presence of ammonium urate urolithiasis was recorded.

Results: A total of 363 dogs were included. The overall incidence of ammonium urate urolithiasis was 19.3%. Dogs with extrahepatic portosystemic shunts were more likely to have urolithiasis compared to those with intrahepatic portosystemic shunts (32.2% vs. 8.0%). Dogs with urolithiasis were older (median 40 vs. 8 months) and more likely to be neutered males (51.4% vs. 9.8%). Ammonia was significantly lower in dogs with urolithiasis. Dogs with urolithiasis were more likely to have haematuria on dipstick analysis and sediment examination.

Clinical significance: Dogs with extrahepatic portosystemic shunts were more likely to have urolithiasis when compared to dogs with intrahepatic portosystemic shunts. Dogs with higher ammonia levels were less likely to have ammonium urate urolithiasis, and older dogs, neutered males, or those with evidence of haematuria had an increased incidence of urolithiasis.

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References

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