A 5-year retrospective epidemiological and compositional study of canine and feline uroliths in Tehran, Iran (2019 - 2024).

This study provided a comprehensive analysis of 145 urinary bladder stone cases diagnosed in dogs and cats over a 5-year period at a private veterinary hospital. The aim was to evaluate demographic patterns, urolith composition, and species-specific trends to enhance understanding and improve management of urolithiasis in companion animals. A retrospective study was conducted on clinical records, including patient demographics (species, breed, age, sex), urolith composition, and stone size. Chemical composition of uroliths was determined using qualitative chemical analysis. Statistical analyses were performed to identify significant associations between patient demographics and urolith composition. Of the 145 cases, 80 were dogs (55.17%) and 65 were cats (44.82%). In dogs, calcium oxalate stones predominated (65.00%) followed by struvite stones (30.00%) and mixed compositions (5.00%). Conversely, cats exhibited a higher prevalence of struvite stones (55.00%), with calcium oxalate accounting for 40.00% and mixed stones for 5.00%. Larger stones (10.00 - 20.00 mm) were more common in female dogs, while cats generally presented with fewer and smaller stones. No statistically significant temporal trend in urolith composition was observed for either species during the study period. Stone color distribution varied by species including cream and brown stones being most common in dogs and cats, respectively. This study established baseline epidemiological data on urolithiasis for this region, revealing significant species-specific differences in stone composition. The high prevalence of calcium oxalate in dogs and struvite in cats highlighted the need for tailored clinical management and provides a crucial benchmark for future regional and global comparative studies.