Page 557 - Problem-Based Feline Medicine

24 – THE ANEMIC CAT 549

Diagnosis tion defect. Mechanisms include folic acid antagonist
administration, dietary insufficiency, malabsorption
Feline leukemia virus infection, drugs and toxins
and congenital defect.
should be excluded.
History of chronic (> 2 weeks) administration of folic
CBC generally reveals severe normocytic-normo-
acid antagonists including pyrimethamine and sulfa
chromic, non-regenerative anemia with normal neu-
drugs.
trophil and platelet numbers.
Clinical signs are associated with anemia and those of
Bone marrow examination reveals either maturation
the disease the antibiotic was being used to treat.
arrest or lack of erythroblasts.
Diarrhea and weight loss may be associated with mal-
IFA or polymerase chain reaction for FeLV should be
absorption syndromes.
performed on bone marrow cells.
The cat may have been fed a folic acid deficient diet
Spherocytes, positive direct Coomb’s test results and
like tuna.
autoagglutination might be present in some affected
animals.
Diagnosis
Differential diagnosis Macrocytic-hypochromic, or macrocytic-normochromic
non-regenerative anemia with nuclear remnants.
FeLV, myelophthitic disease, ehrlichiosis, anemia of
chronic disease. Mean corpuscular volume >55 fl.

Neutropenia with hypersegmented neutrophils may be
Treatment present
Immunosuppressive therapy as described for regenera- History of drug administration.
tive hemolytic anemia (see page 533) should be pre-
Bone marrow cytology shows erythroid hyperplasia
scribed.
and megaloblastic changes.
Several blood transfusions may be required; since the
Serum folate concentrations decreased (normal =
bone marrow is involved, response to therapy is more
13–38 μg/L) with normal cobalamin concentrations.
delayed.
Recombinant erythropoietin can be administered as Treatment
described for renal failure-associated non-regenerative
anemia (see page 540), but is unlikely to be effective Stop drug treatment.
since maximal erythropoietin responses are likely
Folic acid supplementation at 0.004–0.01 mg/kg/day,
occurring.
PO.
Signs resolve within 3 weeks of supplementation.
FOLIC ACID ANTAGONISM/DEFICIENCY
IRON DEFICIENCY
Classical signs

● Lethargy, anorexia and depression. Classical signs
● Lethargy, anorexia and depression.
Clinical signs
Clinical signs
Folic acid is required for DNA synthesis, which is
important in red blood cell production; insufficient Most commonly develops from chronic loss of blood
folic acid results in macrocytic anemia as a matura- from the body.