Keys to ureteral stenting: A case study

Keys to ureteral stenting: A case study

Nov 01, 2010

In the first of new series for DVM Newsmagazine, this case-study approach to radiology is offered to showcase the many possibilities in managing medical cases through imaging. This case involves multiple uroliths obstructing a cat's ureter and kidney.

Initial findings

  • Signalment: 10-year-old female spayed domestic shorthaired cat
  • Presenting complaint: Decreased appetite, vomiting and weight loss for about two weeks and one episode of hematuria
  • Pertinent history: Mild azotemia with creatinine between 2.5 and 3.1 mg/dl for about two years
  • Medications: Prescription Diet k/d (Hill's Pet Nutrition), famotidine (2.5 mg every 24 hours)
  • Physical examination findings: Quiet and alert; body condition score 4/9; renomegaly (right) and a left small kidney (about 2.5 to 3 cm); no pain on abdominal palpation

Figure 1: A lateral radiograph of the patient in this case. Note that the left kidney is larger than the right and that multiple stones are inside the left ureter and both renal pelves.

Diagnostic evaluation
  • Complete blood count: Mild normochromic normocytic nonregenerative anemia (24%)
  • Serum chemistry profile: Blood urea nitrogen 108 mg/dl; creatinine 5.6 mg/dl; phosphorus 12 mg/dl; potassium 4.7 mEq/L; sodium 147 mEq/L
  • Urinalysis: Urine specific gravity 1.015; no white blood cells; 10 to 20 red blood cells/hpf; no crystals, no bacteria seen; pH 6.5
  • Abdominal radiographic examination: See Figure 1
  • Abdominal ultrasonographic examination: See Figures 2A & 2B
  • Urine culture: Negative
  • Blood pressure: 130 mm Hg systolic

Figures 2A & 2B: Abdominal ultrasonograms of the left kidney documenting severe hydronephrosis (12 mm diameter) and hydroureter with multiple stones in the ureteral lumen that are shadowing.
Problem list
  • Chronic renal- and acute post-renal azotemia
  • Multiple ureteroliths and associated ureteral obstruction due to stone disease
  • Nephrolithiasis

Presumptive diagnosis

Left ureteral obstruction secondary to ureterolithiasis with associated chronic kidney disease (small right kidney and history of renal azotemia).

Treatment options

  • Multiple ureterotomies
  • Ureteral reimplantation
  • Ureteral stenting