Page 535 - Problem-Based Feline Medicine

24 – THE ANEMIC CAT 527

QUICK REFERENCE SUMMARY
Diseases causing an anemic cat
REGENERATIVE ANEMIA (> 60 000 RETICULOCYTES/ML) – HEMOLYSIS

ANOMALY
● Hereditary hemolytic anemia (pyruvate kinase deficiency, osmotic fragility, porphyria)
Rarely, diseases like pyruvate kinase deficiency in Abyssinian cats result in hemolysis. Hereditary
hemolytic anemias usually result in mild, intermittent regenerative anemia and weight loss.
Porphyria produces severe macrocytic, hypochromic anemia and brown discoloration of the teeth.
METABOLIC
● Hypophosphatemia* (p 534)
Extreme hypophosphatemia during treatment of ketoacidotic diabetic cats can result in increased
red blood cell fragility. Onset of anemia, muscle weakness or ataxia after intensive treatment of a
diabetic cat is suspicious.

● Microangiopathic hemolytic anemia* (p 534)
Red blood cells can be damaged when passing through abnormal vessels resulting in schistocytes.
Disseminated intravascular coagulation (fibrin strands), dirofilariasis, and splenic tumors or
hematomas can damage red blood cells. Lethargy, anorexia and depression may be present in addi-
tion to the signs of the underlying disease. Schistocytes are evident on thin blood smears but are
hard to detect in cats.
INFECTIOUS

● Hemoplasmosis*** (p 530)
In most parts of the world, the most common causes of hemolytic anemia are infectious, especially
from Mycoplasma haemofelis, and Candidatus M. haemominutum infection. Typically cats present
with pale mucous membranes, anorexia, mild to marked depression and sometimes fever.
● Cytauxzoonosis
Typically cats present with pale mucous membranes, anorexia, depression and fever. Dyspnea,
collapse and death occur commonly.

IMMUNE
● Immune-mediated hemolytic anemia** (p 532)
Primary immune-mediated hemolytic anemia in cats is unusual when compared to dogs but sec-
ondary immune-mediated red cell destruction can occur secondary to drugs, vaccines and infec-
tious agents. Anemia is usually regenerative but may be non-regenerative. Depression, and variable
fever, splenomegaly and icterus occur. Agglutination or a positive Coomb’s test are indicative of
an immune-mediated process.

TOXINS
● Drugs and toxins** (p 533)
Some drugs like acetaminophen and benzocaines and other toxins result in Heinz body anemia in
cats which is usually regenerative. Other drugs and toxins induce non-regenerative anemia (see
below). Lethargy, anorexia, weakness, pale mucous membranes and elevated heart and respiratory
rates are often present.

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