Page 221 - Problem-Based Feline Medicine

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13 – THE CAT WITH DISCOLORED URINE 213

or serum is pink with hemoglobinuria but clear with Evidence of cardiac disease is usually present with aortic-
myoglobinuria. saddle thrombus.
Anemia may be present. Snake bite may be complicated by a coagulopathy and
● Plasma and serum are pink. hemolysis, resulting in hemoglobinuria, hematuria, as
● May be Coombs positive if associated with well as myoglobinuria.
immune-mediated hemolytic anemia.
CLOUDY WHITE OR WHITE URINE

MYOGLOBINURIA Cloudy or white urine suggests the presence of pus,
lipid, or crystals.
Classical signs
Diagnosis is aided by microscopic examination of urine
● Urine is red or brown. sediment for pyuria, crystalluria or lipiduria.
● Muscle weakness or pain present.
Consideration of the clinical signs aids diagnosis. Signs
of lower urinary tract disease or systemic illness may or
See main reference on page 950 (The Cat With General-
may not be present.
ized Weakness) for details on snake bite, and page 915
(The Weak and Ataxic or Paralyzed Cat) for details on
aortic thrombosis.
CRYSTALLURIA***
Clinical signs
Classical signs
Myoglobinuria is most commonly associated with
● White or cloudy urine.
aortic thrombosis or snake bite. Rarely, toxoplasmo-
● May or may not be associated with
sis results in myoglobinuria or bilirubinuria in young
urolithiasis.
cats.
Urine is red, brown, or black. See main reference on page 184 (The Cat Straining to
Urinate) for details on urolithiasis.
Muscle weakness or pain is present.
Vomiting, anorexia, or other polysystemic signs may be
present. Clinical signs
Arrhythmia or heart murmur may be present if an Crystalluria may result in white or cloudy urine if
aortic saddle thrombus is present secondary to underly- the crystalluria is marked or the urine is concentrated.
ing cardiomyopathy.
Crystalluria may occur with or without urolithiasis, and
uroliths may be present without crystalluria.
Diagnosis ● Uroliths in the lower urinary tract may be associ-
ated with hematuria, stranguria, inappropriate uri-
Urine is red, brown or black.
nation, pollakiuria or urethral obstruction.
No RBCs observed on microscopic examination of ● Uroliths in the upper urinary tract may be associ-
urine sediment. ated with hematuria or renal pain.
● Uroliths may not be associated with clinical signs.
Plasma and serum are normal in color.
Hyperkalemia and metabolic acidosis is often present
if due to muscle injury. Diagnosis
There is evidence for other organ dysfunction if myo- Crystals are identified on microscopic examination of
globinuria is associated with toxoplasmosis, including urine sediment.
dyspnea, anemia, vomiting, diarrhea, neurological ● Struvite crystals are typically “coffin-lid”-shaped
signs or jaundice. or amorphous, and occur in a neutral to alkaline pH.