Epidemiology of feline urolithiasis in Mexico (2006-2017).

OBJECTIVES: The objectives of this study were to identify the proportions of different types of uroliths, characterize the population of cats that present with urolithiasis and determine possible predisposing factors in a population of Mexican cats. METHODS: This study analyzed clinical specimens of feline urolithiasis submitted to our laboratory in the period from 2006 to 2017. The mineral composition of the uroliths was determined by qualitative and quantitative mineral analyses, performed by stereoscopic microscopy and infrared spectroscopy. RESULTS: In the population studied, 54.3% of all uroliths were calcium oxalate, followed by 32.1% struvite and 7.4% purine (urate and xanthine) uroliths, with other types accounting for 6.2% of submissions. The male:female ratio was 1.2:1. Calcium oxalate submissions were predominantly from males and struvite submissions were predominantly from females. The age of the cats with stone submissions ranged from 6 months to 17 years. In cats with calcium oxalate uroliths, 52.3% were aged 7 years or older. Cats with struvite uroliths were younger, with 65.4% younger than 6 years of age. Almost 90% of all submitted uroliths were from domestic shorthair cats. CONCLUSIONS AND RELEVANCE: This is the first epidemiologic study of urolithiasis in cats in Mexico. Age and sex predispositions to common uroliths were identified, as males aged ≥7 years primarily presented with calcium oxalate uroliths and females aged <6 years primarily presented struvite uroliths. Cases of urolithiasis of genetic origin, including xanthinuria and cystinuria, were also detected, in addition to silicate uroliths.

Evaluation of clinical and immunopathological features of different infective doses of Trypanosoma cruzi in dogs during the acute phase.

Infection with Trypanosoma cruzi is a major risk in Latin America, and dogs are believed to be good models for evaluating Chagas disease. Here, we evaluated the clinical and immunopathological alterations developed by mongrel dogs experimentally infected with different infective doses (2,000, 20,000, and 200,000 metacyclic trypomastigotes of Sylvio X10/4 strain kg(-1) via intraperitoneal). Clinical and electrocardiographic parameters, as well as antibody production and pathologic lesions were evaluated. All three doses of this strain of T. cruzi induced a similar pattern of infection characterized by cardiac arrhythmias and severe and diffuse myocarditis. Specific anti-T. cruzi IgG indicated seroconversion by day 14 after infection, and IgG levels increased during the period of evaluation. Mortality was observed only in dogs infected with the medium or high parasite doses, but not in the group infected with a low dose of 2,000 parasites kg(-1). Infection with a low dose of parasites provides an excellent nonlethal model to evaluate the immunopathology of the acute disease in dogs infected with the Sylvio X10/4 strain of T. cruzi.