Evidence cluster — dietary management of calcium oxalate uroliths in dogs (peer-reviewed, Europe PMC + PubMed)

Representative peer-reviewed studies (verbatim abstracts)

The following studies were retrieved from Europe PMC / PubMed and are reproduced verbatim. Interpretive synthesis is left to the API user.

PMID:41961373 — Serum and urine metabolomic profiling in Miniature Schnauzer dogs with and without calcium oxalate urolithiasis.

Source: Metabolomics 2026
Metabolomics. 2026 Apr 10;22(2):50. doi: 10.1007/s11306-026-02429-1.

Serum and urine metabolomic profiling in Miniature Schnauzer dogs with and without calcium oxalate urolithiasis.

Coffey EL(1), Gomez A(2), Tate NM(3), Baker LA(4), Lulich JP(5), Furrow E(5).

Author information: (1)Department of Veterinary Clinical Sciences, University of Minnesota, Saint Paul, MN, USA. coffe099@umn.edu. (2)Department of Animal Science, University of Minnesota, Saint Paul, MN, USA. (3)Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, USA. (4)Department of Animal and Dairy Sciences, University of Wisconsin, Madison, WI, USA. (5)Department of Veterinary Clinical Sciences, University of Minnesota, Saint Paul, MN, USA.

INTRODUCTION: Calcium oxalate (CaOx) urolithiasis is associated with metabolic disorders, including dyslipidemia. Improved understanding of underlying metabolic derangements is needed. The Miniature Schnauzer presents an opportunity to investigate connections between hyperlipidemia and CaOx stones, as both are prevalent in the breed. OBJECTIVES: To characterize lipidomic (serum) and metabolomic (serum and urine) profiles in Miniature Schnauzers with (cases) and without (controls) CaOx urolithiasis. METHODS: Ultrahigh performance liquid chromatography-tandem mass spectroscopy was performed on serum from cases (n = 15) and controls (n = 27) for lipidomic and metabolomic analysis. Urine metabolomics was included for a subset of dogs. Ten metabolites with previously established biological links to urolithiasis were prespecified as "high priority." Cases and controls were compared to identify differentially abundant metabolites (FDR-adjusted q-values). RESULTS: No lipid species were differentially abundant. Three serum metabolites differed between groups (all lower in cases): 10-undecenoate, N-delta-acetylornithine, and glutarate (q-values 0.005, 0.03, and 0.009, respectively). Cluster analysis of high priority metabolites identified a subset of cases with distinct profiles, characterized by lower citrate and higher phosphate, glycine, and hippurate. Urinary profiles exhibited 202 differentially abundant metabolites, including higher acetylcarnitine and carnitine in cases (q-values 0.002 for both). CONCLUSIONS: No differences in lipids were identified between Miniature Schnauzers with and without CaOx stones. Distinct metabolic subsets of stone formers might exist within the breed. Reduced N-delta-acetylornithine in stone formers is also reported in human stone formers and might reflect dietary acid load. Acetylcarnitine and carnitine enrichment in the urine of stone formers also warrants further exploration.

DOI: 10.1007/s11306-026-02429-1 PMCID: PMC13068756 PMID: 41961373 [Indexed for MEDLINE]

Conflict of interest statement: Declarations. Competing interests: The authors declare no competing interests. Ethical approval: Sample collection was approved by the University of Minnesota Institutional Animal Care and Use Committee (protocols 1207 A-17243, 1509–33019 A, and 1807–36213 A). Written, informed owner consent was acquired prior to sample collection.

Abstract (verbatim excerpt):

JOURNAL:Metabolomics 2026

Metabolomics. 2026 Apr 10;22(2):50. doi: 10.1007/s11306-026-02429-1.

Serum and urine metabolomic profiling in Miniature Schnauzer dogs with and without calcium oxalate

PMID:41897919 — Neutrophil Extracellular Traps Promote Urolithiasis Formation in Dogs: A Preliminary Study.

Source: Animals (Basel) 2026
Animals (Basel). 2026 Mar 17;16(6):942. doi: 10.3390/ani16060942.

Neutrophil Extracellular Traps Promote Urolithiasis Formation in Dogs: A Preliminary Study.

Shi H(1)(2), Ren R(1), Zeng L(1), Zhang Y(1), Zhang W(1), Qiao M(1), Jin Y(1)(2).

Author information: (1)College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. (2)China Agricultural University Veterinary Teaching Hospital, Beijing 100193, China.

Canine urolithiasis is a common and highly recurrent urinary tract disease, with struvite and calcium oxalate being the predominant stone types. Stone formation has traditionally been attributed to urinary physicochemical factors, including urine pH, mineral supersaturation, and urinary tract infection. However, these factors alone cannot fully explain the persistent growth and rapid progression of stones in affected dogs. In this study, we provide evidence that innate immune mechanisms, particularly neutrophil extracellular traps (NETs), are associated with canine urolith formation. We found that neutrophils, key cells of the innate immune system, release neutrophil extracellular traps composed of DNA and antimicrobial proteins, which are consistently present within urinary stones and their surrounding microenvironments. Common canine urinary pathogens were shown to trigger this response, and these immune-derived structures promoted crystal nucleation, aggregation, and stone growth in experimental systems. Importantly, enzymatic degradation of NETs by DNase I attenuated NET-associated stone growth under in vitro conditions. These findings suggest that canine urinary stones develop not only as a consequence of physicochemical factors, but also in association with inflammation-driven biomineralization processes involving NETs. Recognizing the contribution of innate immunity provides new insight into stone recurrence and may inform future preventive and therapeutic strategies.

DOI: 10.3390/ani16060942 PMCID: PMC13023266 PMID: 41897919

Conflict of interest statement: The authors declare no conflicts of interest.

Abstract (verbatim excerpt):

JOURNAL:Animals (Basel) 2026

Animals (Basel). 2026 Mar 17;16(6):942. doi: 10.3390/ani16060942.

Neutrophil Extracellular Traps Promote Urolithiasis Formation in Dogs: A Preliminary Study.

Shi H(

PMID:42414994 — Off-label use of dapagliflozin in a dog with recurrent calcium oxalate urolithiasis: a case report.

Source: BMC Vet Res 2026
BMC Vet Res. 2026 Jul 7. doi: 10.1186/s12917-026-05684-5. Online ahead of

print.

Off-label use of dapagliflozin in a dog with recurrent calcium oxalate urolithiasis: a case report.

Pakhawala J(1).

Author information: (1)Department of Internal Medicine, Schwarzman Animal Medical Center, New York, NY, USA. Jpakhawala@gmail.com.

BACKGROUND: Calcium oxalate (CaOx) urolithiasis is a common and recurrent condition in dogs, typically managed with dietary modification, thiazide diuretics, and potassium citrate. In human medicine, sodium-glucose cotransporter 2 (SGLT2) inhibitors such as dapagliflozin are increasingly used to manage diabetes mellitus and chronic kidney disease and have been shown to alter urinary factors associated with nephrolithiasis. Their effects in veterinary patients, however, remain uncharacterized. This case report describes the novel off-label use of dapagliflozin in a dog with refractory CaOx cystolithiasis despite standard preventive therapies. CASE PRESENTATION: An 8-year-old neutered male Chihuahua with a history of recurrent CaOx urolithiasis experienced multiple episodes of stone recurrence despite adherence to a therapeutic stone-prevention diet, hydrochlorothiazide, and potassium citrate. Dapagliflozin was initiated off-label as adjunctive therapy to evaluate its potential impact on urinary calcium excretion. Pre- and post-treatment urinalyses and urine calcium-to-creatinine ratios were compared. Following initiation, the dog developed glucosuria, acidic urine, and increased urine specific gravity, while urinary calcium-to-creatinine ratios remained elevated. The medication was discontinued after 12 days due to concerns about underhydration. CONCLUSIONS: Short-term SGLT2 inhibition combined with a thiazide diuretic did not reduce hypercalciuria and may increase lithogenic risk if fluid intake is insufficient to offset the osmotic diuresis. This case underscores the importance of hydration monitoring and highlights potential pharmacologic interactions when using SGLT2 inhibitors off-label in dogs. Further controlled studies are needed to elucidate their safety and therapeutic role in managing CaOx urolithiasis in veterinary patients.

DOI: 10.1186/s12917-026-05684-5 PMID: 42414994

Conflict of interest statement: Declarations. Ethics approval and consent to participate: Owner informed consent for all diagnostic and therapeutic interventions, as well as for inclusion of anonymized clinical data in this case report, was obtained at the time of treatment. Consent for publication: Not applicable. Competing interests: The author declare no competing interests.

Abstract (verbatim excerpt):

JOURNAL:BMC Vet Res 2026

BMC Vet Res. 2026 Jul 7. doi: 10.1186/s12917-026-05684-5. Online ahead of

print.

Off-label use of dapagliflozin in a dog with recurrent calcium oxalate urolithiasis: a c

PMID:41742526 — Outcomes of medical dissolution for suspected struvite uroliths in dogs using a therapeutic multipurpose urinary diet and antimicrobial therapy.

Source: J Vet Intern Med 2026
J Vet Intern Med. 2026 Jan 21;40(1):aalaf061. doi: 10.1093/jvimsj/aalaf061.

Outcomes of medical dissolution for suspected struvite uroliths in dogs using a therapeutic multipurpose urinary diet and antimicrobial therapy.

Toillion AR(1), Gilyot S(1), Lulich JP(2), Furrow E(2).

Author information: (1)Hill's Pet Nutrition, Inc., Topeka, KS 66601, United States. (2)Department of Veterinary Clinical Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN 55108, United States.

BACKGROUND: The consensus recommendation is to medically dissolve suspected struvite uroliths in dogs. However, more data is needed on outcomes for protocols using therapeutic multipurpose urinary foods formulated for both struvite urolith dissolution and calcium oxalate urolith prevention. HYPOTHESIS/OBJECTIVES: To describe outcomes for medical dissolution of suspected struvite uroliths in dogs using a therapeutic multipurpose urinary food and concurrent or recent antimicrobial therapy. ANIMALS: Thirteen client-owned dogs with suspected struvite uroliths. METHODS: Single-institution, retrospective case series (observational) of dogs fed a therapeutic multipurpose urinary food for dissolution of suspected struvite uroliths. Dogs had to be treated with antimicrobials concurrently or have an absence of bacteriuria on urine microbial culture after recently completed antimicrobial therapy. Follow-up abdominal imaging was required. Patient and urolith characteristics, dissolution outcomes, and complications were summarized. RESULTS: Complete urolith dissolution occurred in 9 (8 with cystoliths and 1 with nephroliths) of 13 dogs included in the study. Mean time until documentation of complete dissolution was 71 ± 52 days. Eight of the dogs with complete dissolution had bacteriuria less than 60 days prior to urolith diagnosis. Mean duration of antimicrobial therapy for dogs with successful dissolution was 66 ± 49 days. All dogs without complete dissolution had uroliths with non-struvite shells (composed of 80%-100% calcium). No dog developed a urethral obstruction during the dissolution trial. CONCLUSIONS AND CLINICAL IMPORTANCE: Struvite uroliths can be effectively dissolved in dogs with a therapeutic multipurpose urinary food and antimicrobial therapy. A non-struvite urolith layer is a common cause of unsuccessful dissolution.

DOI: 10.1093/jvimsj/aalaf061 PMCID: PMC12881935 PMID: 41742526

Conflict of interest statement: Alyssa R. Toillion is employed by Hill’s Pet Nutrition, Inc. Selena Gilyot is a former employee of Hill’s Pet Nutrition, Inc.

Abstract (verbatim excerpt):

JOURNAL:J Vet Intern Med 2026

J Vet Intern Med. 2026 Jan 21;40(1):aalaf061. doi: 10.1093/jvimsj/aalaf061.

Outcomes of medical dissolution for suspected struvite uroliths in dogs using a therapeu

PMID:41001835 — In Vivo Radiographic Characteristics Associated With the Mineral Composition of Calcium Oxalate, Struvite, and Cystine Lower Urinary Tract Uroliths in Dogs.

Source: J Vet Intern Med 2025
J Vet Intern Med. 2025 Nov-Dec;39(6):e70252. doi: 10.1111/jvim.70252.

In Vivo Radiographic Characteristics Associated With the Mineral Composition of Calcium Oxalate, Struvite, and Cystine Lower Urinary Tract Uroliths in Dogs.

Pulido Vega D(1), Motteau-Lévêque M(2), Maurey C(3), Mortier J(1).

Author information: (1)Service of Diagnostic Imaging, École Nationale Vétérinaire d'Alfort, Maisons-Alfort, France. (2)École Nationale Vétérinaire d'Alfort, Maisons-Alfort, France. (3)Service of Internal Medicine, École Nationale Vétérinaire d'Alfort, INRAE, ANSES, UMR Virology, Laboratoire de Santé Animale, Maisons-Alfort, France.

BACKGROUND: Identifying urolith mineral composition (UMC) is crucial for treatment and prevention; however, current data rely on macroscopic or ex vivo studies. OBJECTIVES: To describe in vivo radiographic characteristics of canine lower urinary tract (LUT) uroliths and identify discriminating radiographic features among UMC types. ANIMALS: Two hundred and two dogs with LUT uroliths composed of ≥ 70% calcium oxalate (n = 109), struvite (n = 58), or cystine (n = 35). METHODS: Retrospective cross-sectional study. Radiographs were evaluated for urolith size, shape, surface, borders, internal architecture, and quantitative radiopacity, and also assessed using a ratio of urolith-to-L5 vertebra pixel values (UOR). The diagnostic performance of urolith size and UOR was assessed with receiver operating characteristics (ROC) curves, calculating the area under the ROC curve (AUC). RESULTS: Calcium oxalate uroliths were often highly radiopaque, associated with concurrent nephroliths, had unique shapes such as bosselated or spiculated, and less commonly ovoid. Struvite uroliths were larger (median: 15 mm; IQR: 8.1-25.8 mm) with a cut-off of ≥ 11 mm (AUC = 0.82, p < 0.001; specificity: 91%, sensitivity: 67%) and were associated with pyramidal shapes or solitary cystoliths. Cystine uroliths had lower radiopacity (median UOR: 0.71; IQR: 0.63-0.80), with a cut-off of UOR ≤ 0.83 (AUC = 0.81, p < 0.001; specificity: 67%, sensitivity: 84%). CONCLUSIONS AND CLINICAL IMPORTANCE: In vivo radiographic characteristics such as size, shape, and radiopacity can help differentiate LUT mineral compositions, enabling non-invasive diagnosis and guiding treatment.

DOI: 10.1111/jvim.70252 PMCID: PMC12464727 PMID: 41001835 [Indexed for MEDLINE]

Conflict of interest statement: Authors declare no off‐label use of antimicrobials. The authors declare no conflicts of interest.

Abstract (verbatim excerpt):

JOURNAL:J Vet Intern Med 2025

J Vet Intern Med. 2025 Nov-Dec;39(6):e70252. doi: 10.1111/jvim.70252.

In Vivo Radiographic Characteristics Associated With the Mineral Composition of Calcium Oxalat

PMID:42154599 — Protocol for establishing an infrared spectral reference library for canine urolith analysis.

Source: STAR Protoc 2026
STAR Protoc. 2026 Jun 19;7(2):104588. doi: 10.1016/j.xpro.2026.104588. Epub

2026 May 19.

Protocol for establishing an infrared spectral reference library for canine urolith analysis.

Ruiz-Ramírez V(1), Silva-Agredo J(1), Manrique-Moreno M(2).

Author information: (1)Chemistry Institute, Faculty of Exact and Natural Sciences, University of Antioquia - UdeA, Medellin, Antioquia 050010, Colombia. (2)Chemistry Institute, Faculty of Exact and Natural Sciences, University of Antioquia - UdeA, Medellin, Antioquia 050010, Colombia. Electronic address: marcela.manrique@udea.edu.co.

Canine urolithiasis is a common, recurrent urinary disorder in dogs, posing significant clinical and economic burdens. Breed predispositions suggest genetic and metabolic influences. Accurate determination of urolith composition is essential for effective treatment and prevention. Here, we present a protocol to generate an infrared spectral library of key mineral components for canine urolith analysis. We describe steps for mineral selection, preparation of reference spectra, and library construction. We then detail a workflow for reliable urolith analysis.

DOI: 10.1016/j.xpro.2026.104588 PMCID: PMC13213795 PMID: 42154599 [Indexed for MEDLINE]

Conflict of interest statement: Declaration of interests The authors declare no competing interests.

Abstract (verbatim excerpt):

JOURNAL:STAR Protoc 2026

STAR Protoc. 2026 Jun 19;7(2):104588. doi: 10.1016/j.xpro.2026.104588. Epub