Efficacy of medical dissolution for suspected struvite cystoliths in dogs

Abstract

Background Medical dissolution of struvite uroliths in dogs is commonly recommended, but data on success rates and complications are limited. Objectives To evaluate the efficacy of medical dissolution for suspected struvite cystoliths in dogs. Animals Fifty client‐owned dogs fed a therapeutic dissolution diet, with or without administration of antimicrobials, for treatment of suspected struvite cystoliths. Methods Single institution, retrospective case series. Medical records were reviewed for dogs with at least 1 follow‐up visit. Dissolution success, complications, and possible predictors of success were evaluated. Results Full dissolution of cystoliths was achieved in 58% (29/50) of dogs within a median of 35 days (range, 13‐167). Of 21 dogs without success, 7 each had partial dissolution, no dissolution, or undetermined outcome. Uroliths containing >10% nonstruvite mineral were common in the nonsuccess group (11/16 analyzed). Maximum urolith diameter, number of uroliths, and baseline urine pH did not differ significantly between dogs with and without success. Dissolution was more likely in dogs receiving antimicrobial therapy (OR = 16.3, 95% confidence interval 1.9‐787.4, P = .002). Adverse events occurred in 9 dogs (18%); urethral obstructions were the most common, but 3 of 4 dogs with this complication were obstructed on presentation, before trial initiation. Conclusions and Clinical Importance Results support a medical dissolution trial for dogs with suspected struvite cystoliths. If no reduction in urolith size or number occurs by 1 month, a nonstruvite composition is likely, and alternative interventions should be considered. Dogs presenting with urethral obstructions should not be considered candidates for medical dissolution.

New insights into the etiology, risk factors, and pathogenesis of pancreatitis in dogs: Potential impacts on clinical practice

“…While the study investigated the effect of dietary fat content on serum cPLI concentration, this study cannot be extended to infer the effects of high fat diets on the development of pancreatitis. In another study 2/50 dogs receiving a struvite dissolution diet (5.7 g/100 kcal, 26.3% crude fat) were noted to develop pancreatitis 4 . A control group was not used as part of the study design and the basis for a diagnosis of pancreatitis is not reported.…”

“…High fat diet [2][3][4] Ingestion of unusual food items 5,6 Ingestion of table scraps 5 Ingestion of trash 5 Drugs/toxins L-asparaginase 7,8 Phenobarbital and potassium bromide 9-11a Azathioprine [12][13][14] Potentiated sulfonamides 15 Organophosphates 12,16 Corticosteroids, 12,17b Furosemide 12 Atovaquone/proguanil (Malarone) 18 N-methyl-glucamine (Meglumine), 19b…”

“…In another study 2/50 dogs receiving a struvite dissolution diet (5.7 g/100 kcal, 26.3% crude fat) were noted to develop pancreatitis. 4 A control group was not used as part of the study design and the basis for a diagnosis of pancreatitis is not reported. Given the current literature definitive conclusions on the significance of high levels of dietary fat in the development of pancreatitis cannot be made.…”

Risk Factors and Clinical Presentation in Dogs with Increased Serum Pancreatic Lipase Concentrations—A Descriptive Analysis

“…Additional research is therefore needed to further investigate the relationship between naturally occurring renal disease and pancreatitis. Renal and urinary diets are often higher in dietary fat than standard adult maintenance diets, and this could be a contributing factor in this relationship; indeed, 10 dogs in our study were receiving such diets [ 33 ]. However, dietary fat level was not definitively assessed, and as such, this remains speculative.…”

d,l-Methionine in combination with amoxicillin–clavulanic acid successfully dissolves spontaneously occurring infection-induced struvite urocystoliths in dogs: a pilot study

“…1,2 Although the relative prevalence of different types of canine uroliths has changed over the last 20 years, struvite remains one of the most common canine urolith types encountered, comprising 36% d,l-Methionine in combination with amoxicillin-clavulanic acid successfully dissolves spontaneously occurring infection-induced struvite urocystoliths in dogs: a pilot study to 43% of canine urolith submissions encountered at urolith analysis centers, including the Minnesota Urolith Center. 2,3,4 The majority (95%) of struvite uroliths occur in the lower urinary tract. 1 Most infection-induced struvite uroliths are amenable to medical treatment for dissolution using a diet change to decrease urine concentrations of struvite calculogenic compounds and an antimicrobial agent.…”