'PGDesign / Universidade Federal do Rio Grande do Sul'
Abstract
Background: Nephrolithiasis is a condition frequently observed in felines, with or without concomitant chronic kidney disease, constituting the major cause of ureteral obstruction and causing progressive damage to the renal parenchyma. About 90% of nephrolites are composed of calcium oxalate, which cannot dissolve, and its incidence has increased substantially in recent years, along with its recurrence. There are functional foods known as nutraceuticals provides health benefits such as renoprotection. Due to these benefits and the high prevalence of nephrolithiasis in feline species, the present study aimed to evaluate the efficacy of the association of some nutraceuticals in the dissolution of nephrolites.Materials, Methods & Results: The included cats had an ultrasound diagnosis of nephrolithiasis that, on clinical examination, showed: (i) the absence of previous or concomitant treatment for urinary infections and/or vesical and renal lithiasis; (ii) absence of genitourinary clinical manifestations; (iii) absence of obstructive processes; and (iv) absence of concomitant ureterolithiasis. We separated 51 cats with nephrolithiasis into 2 groups: control (n = 12) and study (n = 39). The control group received a placebo and the study group, nutraceuticals (magnesium chelate, resveratrol, vitamin K2, docosahexaenoic acid, and eicosapentaenoic acid). Laboratory tests (blood and urine) and abdominal imaging (ultrasound) were performed at day 0 and 30 days after enrollment. Monitoring the therapeutic efficacy in both groups was performed on day 30 for the CG and on days 30, 60, and 90 for the EG. The CG cats, after this step, were referred to surgery or to the EG, with prior authorization from their tutors. The diameter of nephrolites was significantly different before and after treatment, indicating a reduction in nephroliths over time. During the use of the nutraceutical formulation by the EG and use of placebo by the CG, there were no clinical and/or laboratory manifestations of side effects.Discussion: The dissolution of nephrolites was correlated with the synergism promoted by the combination of nutraceuticals and not with the individual beneficial action of each nutraceutical since nutraceuticals have individually been used in isolation for a long time in veterinary medicine without having yielded the same benefit. Those undissolved were attributed to a different type of mineral composition than the one associated with the nutraceutical compound in this study, such as struvite or ammonium urate, of mixed composition or comprising solidified dried blood, which has shown an increasing increase in use in recent years. The dissolution of nephrolites was correlated with the synergism promoted by the combination of nutraceuticals and not with the individual beneficial action of each nutraceutical since nutraceuticals have individually been used in isolation for a long time in veterinary medicine without having yielded the same benefit. The undissolved nephrolites were attributed to the nephrolites that obtained partial dissolution at the end of 90 days, in that they possibly needed a longer time to obtain complete dissolution or that they present another mineral composition in their nucleus; that is, it is a compound-type urolith. The nutraceutical compound proved to be effective in the dissolution of nephrolites in the cats included in this study, and the time of use (up to 90 days) showed no negative influence on the clinical or laboratory tests during the entire treatment period.Keywords: cats, food supplement, functional foods, natural products, nephrolithiasis, nutraceuticals