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266.e6 Discolored Urine

defect, cystitis, urolithiasis, urethritis, pros- Abdominal ultrasound, look for • Basic imaging (abdominal radiographs and
tatitis/prostatic abscess, prostatic neoplasia, • Renal disease (pyelonephritis, mass, diffuse ultrasound) can rule in or rule out many
VetBooks.ir idiopathic renal hematuria (pp. 428 and • Bladder wall tumor (transitional cell carci- • Color of urine cannot accurately predict urine
infiltration, other)
common causes of discolored urine.
urinary bladder neoplasia, trauma, estrus,
1229)
concentration. Urine specific gravity must
noma, other)
• Pyuria: white blood cells (WBCs) seen
urine may have a low specific gravity.
neoplasia)
on sediment exam (dipsticks notoriously • Prostatic disease (prostatitis, prostatic cysts, be measured because even darkly colored
unreliable). Consider cystitis, pyelonephritis, • Urolithiasis • Bilirubin conjugation and excretion is normal
sterile inflammation (feline lower urinary • Sublumbar lymphadenopathy in the dog but not the cat; therefore, trace or
tract signs/idiopathic cystitis), neoplasia • Other neoplasia/abnormality contributing mild bilirubinuria in dogs may be normal.
(p. 1377). to hemolysis • Seemingly healthy animals with an otherwise
• Hemoglobinuria: positive for blood on normal urinalysis but bright or bizarre
dipstick without intact RBCs on sediment Advanced or Confirmatory Testing colored urine should be suspected of having
exam, accompanied by hemolyzed serum. As dictated by findings for the individual case: ingested water-soluble pigments.
Consider intravascular hemolysis. • Vaginal exam: if cystocentesis clear but
• Myoglobinuria: positive for blood on dipstick hematuria on voided sample in a bitch Technician Tips
without intact RBCs on sediment exam, • Additional laboratory testing: vaginal cytol- • Note color of urine with every urinalysis.
accompanied by clear serum. Consider ogy, urine protein/creatinine ratio, ejaculate • Do not perform cystocentesis if bleeding
muscle damage. exam, investigation of kidney or liver disease disorder or bladder cancer is a possible
• Bilirubinuria: positive on dipstick, often • Advanced imaging: excretory urogram, diagnosis.
hyperbilirubinemia. Consider cholestatic abdominal CT • If red urine clears after centrifugation, the
disease, hepatopathy, and hemolysis. • Cystoscopy problem is hematuria. Because hemoglobin
• Urine concentration: color is often more • Biopsy and myoglobin stay in suspension, urine
obvious in concentrated urine. Pigments color will not change with centrifugation.
or hematuria may not be grossly apparent TREATMENT
in dilute urine. SUGGESTED READING
CBC: rule out anemia (hemolysis), thrombo- Treatment Overview Callens AJ, et al: Urinalysis. Vet Clin North Am
cytopenia (hemostatic defect) • Correct underlying cause based on accurate Small Anim Pract 45(4):621-637, 2015.
Serum biochemistry profile: diagnosis.
• Metabolic diseases (e.g., evidence of hepatic • Rarely, hematuria is severe enough to warrant ADDITIONAL SUGGESTED
diseases or cholestasis) transfusion. READINGS
• Evaluate color of serum Bartges JW, et al: Urolithiasis. Vet Clin North Am
○ Clear: normal; consider myoglobin as PROGNOSIS & OUTCOME Small Anim Pract 45(4):747-768, 2015.
cause for red/dark urine Smee N, et al: UTIs in small animal patients. Part
○ Pink/red: intravascular hemolysis; consider Varies based on underlying cause 2: diagnosis, treatment, and complications. J Am
hemoglobin as cause for red/dark urine Anim Hosp Assoc 49:83-94, 2013.
○ Yellow: icterus PEARLS & CONSIDERATIONS
Urine culture and susceptibility: especially RELATED CLIENT EDUCATION
important if WBCs or bacteriuria identified Comments SHEETS
on sediment exam • Physical exam and minimum laboratory work
Abdominal radiographs, look for (CBC, serum biochemistry profile, urinalysis) Consent to Perform Cystocentesis
• Calculi are essential to help quickly narrow the dif- How to Collect a Urine Sample
• Mass effect ferential diagnosis list.
• Prostatomegaly • Comparisons of urine color to plasma color AUTHOR: Claire M. Weigand, DVM, DACVIM
• Metal in gastrointestinal tract (e.g., zinc) and free-catch versus cystocentesis urine EDITOR: Leah A. Cohn, DVM, PhD, DACVIM
• Enlargement/mineralization of sublumbar samples are simple but important steps for
lymph nodes, suggesting prostatic or urinary narrowing the differential diagnosis list.
bladder neoplasia

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