Page 433 - Problem-Based Feline Medicine

21 – THE YELLOW CAT OR CAT WITH ELEVATED LIVER ENZYMES 425

+/− fever and vomiting. sion include increased heart and respiratory rates which
usually occur when the PCV < 15–18% for acute loss
Lymphadenopathy, or skin, respiratory, and gastro-
and < 12% for more chronic loss. See page 531 (The
intestinal infections secondary to immunosuppression
Anemic Cat).
are seen with FeLV infection.
Antivirals and immunotherapy for FeLV infection.
Diagnosis
Typically anemia is moderate to severe (PCV 12–17%) HEPATOCELLULAR DISEASES
with a reduced hemoglobin < 10 g/dl. (JAUNDICE OR INCREASED LIVER
ENZYMES CAUSED BY HEPATIC
Examine blood smears closely with a reduced PCV for
PARENCHYMAL DISEASES)
presence of red cell parasites (hemobartonellosis).
Saline agglutination and direct Coomb’s tests confirm HEPATIC LIPIDOSIS***
immune-mediated anemia but the Coomb’s test
requires feline specific antibody to be meaningful. Classical signs
Liver enzymes (ALT, ALP) are often normal or ● Obese anorectic female cats are
insignificantly elevated. predisposed.
● Progressive anorexia, vomiting, and
Serologic testing (ELISA or fluorescent antibody) for
diarrhea are common.
FeLV infection.
● Severe jaundice and hepatomegaly are
Polymerase chain reaction assays may be of great ben- present.
efit in documenting infection if available.

Differential diagnosis Pathogenesis
Hepatic and post-hepatic disorders are often chronic The etiopathogenesis is poorly understood and ill-
diseases and are associated with some anemia. In these defined.
instances, the anemia is mild (PCV of 18–27%), non-
Triglycerides accumulate in the liver as a consequence
regenerative and is attributable to anemia of chronic
of imbalanced fat metabolism which is likely multifac-
disease.
torial in origin. These imbalances may include uptake
Hemolytic anemia is usually regenerative unless it is of fatty acids, use of fatty acids for energy (e.g., ketone
detected early (< 4 days) or if stem cells are involved; as production and fatty acid oxidation), production and
may occur with Mycoplasma haemofelis infection or dispersal of lipoproteins throughout the body, and de
immune-mediated red cell destruction. novo synthesis of triglycerides. Many metabolic condi-
tions, nutritional factors, drugs and toxins can cause
Hemolytic anemia associated with FeLV infection may
excessive hepatic fat accumulation (see below).
or may not be regenerative.
Approximately 50% of cats have idiopathic (primary)
hepatic lipidosis in which no underlying medical con-
Treatment dition is detected.
● History of previous obesity is observed in nearly all
Supportive care and antibiotics (doxycycline 5 mg/kg
cats.
PO q 12 h for 21 days or enrofloxacin 5 mg/kg PO q 12
● Anorexia or rapid weight reduction contributes to
h for 7–14 days) for cats with hemobartonellosis.
hepatic fat accumulation. Anorexia may be preceded
Whole blood/packed red cell transfusions, cortico- by a stressful event such as a move to a new house.
steroids (prednisone 1–2 mg/kg PO q 12 h as needed), ● Imbalanced nutrition using caloric- or protein-
and supportive care for immune-mediated anemia. restricted diets, especially if unpalatable, can trig-
Clinical parameters which suggest the need for transfu- ger marked weight loss. Experimentally, dietary