Page 880 - Small Animal Clinical Nutrition 5th Edition

Canine Struvite Urolithiasis 911

VetBooks.ir

Figure 5. Positive-contrast retrograde urethrocystogram obtained 39 Figure 6. Positive-contrast retrograde urethrocystogram obtained
days following diagnosis of uroliths and a vesicourachal diverticu- 226 days following initial assessment. The lower urinary tract
lum. There is no evidence of a vesicourachal diverticulum, but nar- appears normal.
rowing of the lumen of the proximal urethra is still present (arrow).

double-contrast cystography revealed no evidence of uroliths in the lower urinary tract. The vesicourachal diverticulum was still
present but reduced in size (Figure 4). Serum albumin (2.7 g/dl), phosphorus (6.7 mg/dl) and urea nitrogen (2 mg/dl) concentra-
tions had decreased from initial values (Table 2).
Because urolith dissolution was complete and because of diet-related alterations in serum phosphorus and albumin concentra-
tions, the food was changed to a moist product designed for growing dogs (Science Diet Canine Growth), fed twice daily.The oral
antimicrobial agent was continued for an additional two weeks.
Reevaluation of the dog 25 days after the initial diagnosis revealed further reduction in the size of the vesicourachal diverticu-
lum.The dog was forming concentrated urine, but still had microscopic hematuria (Table 1). Serum albumin and phosphorus con-
centrations were normal (Table 2). Antimicrobial therapy was continued.
Fourteen days later (39 days after the initial diagnosis), survey and contrast radiographs revealed no evidence of the vesicourachal
diverticulum or uroliths (Figure 5). However, the urethral lumen adjacent to the prostate gland was still reduced. Nevertheless, the
dog had no clinical signs of lower urinary tract disease. Although bacteria could not be cultured by aerobic techniques, urinalysis
revealed an inflammatory response (Table 1).
No clinical or laboratory evidence of disease was present 73 days after the initial diagnosis (Tables 1 and 2). Antimicrobial ther-
apy was discontinued. Evaluation at 10 months of age revealed a normal dog with no detectable radiographic abnormalities of the
lower urinary tract (Figure 6).

Endnotes
a. Hill’s Pet Nutrition, Inc., Topeka, KS, USA.
b. Pfizer Animal Health, Exton, PA, USA.

Bibliography
Osborne CA, Lulich JP, Bartges JW, et al. Canine and feline urolithiasis: Relationship of etiopathogenesis to treatment and pre-
vention. In: Osborne CA, Finco DR, eds. Canine and Feline Nephrology and Urology. Baltimore, MD: Williams & Wilkins, 1995;
798-888.