Efficacy of medical dissolution for suspected struvite cystoliths in dogs

The main goal of the article to which this summary refers was to evaluate the efficacy of medical dissolution for suspected struvite cystoliths in dogs.

Struvite uroliths correspond to a big percentage of uroliths cases diagnosed in dogs. Currently, the recommended therapy is medical treatment, consisting of a combination of diet and antibiotics.

Fifty dogs were included in the study. The baseline was defined as the start date of the therapeutic urinary diet. The number and size of cystoliths were taken into consideration. Size was measured according to the longest diameter (mm) of the largest cystolith, either visualized on lateral radiograph or on the abdominal ultrasound. The average diameter was 6mm.

The approach that used a therapeutic dissolution diet often combined with antimicrobial drugs was successful in most of the dogs (58%). The median time registered for complete dissolution was 35 days. This kind of medical treatment is not recommended for dogs with urethral obstructions.

One dog suffered from a UTI recurrence during the trial. Only seven (14%) failed to achieve any urolith dissolution. Those uroliths ended up being removed by lithotripsy or cystotomy and after analysis it was concluded that they were composed by >10% of nonstruvite mineral, such as calcium or urate. This kind of medical treatment is not recommended for dogs with urethral obstructions.

Greater success was found in dogs that received antimicrobials during the trial. We don’t have enough information to conclude that the lack of antimicrobial therapy contributed to treatment failure, but it is highly recommended to perform a urine culture in dogs with suspected struvite uroliths, even if they have recently taken antibiotics. It is also recommended to perform abdominal radiographs one month after the diet therapy starts, to assess the efficacy of the treatment.

Wingert A. M., Murray O. A., Lulich J. P., Hoelmer A. M., Merkel L. K. and Furrow E. (2021) Efficacy of medical dissolution for suspected struvite cystoliths in dogs. Journal of Veterinary Internal Medicine, 2021; 1-9 https://doi.org/10.1111/jvim.16252