Page 443 - Problem-Based Feline Medicine

21 – THE YELLOW CAT OR CAT WITH ELEVATED LIVER ENZYMES 435

● Retest again 1 week after initiating therapy. Ultrasound may reveal diffuse parenchymal nodules
● Discontinue diazepam therapy in cats with unex- and an irregular liver margin.
plained increases in liver enzyme activities.
Histologic evaluation of liver biopsy specimens is
Peractin is a more effective appetite stimulant, and has required for definitive diagnosis.
not been reported to have serious idiosyncratic reactions. ● Microscopic lesions show both fibrosis and abnor-
mal regenerative nodules.
● Tissues may be obtained by ultrasound-guided
CIRRHOSIS
biopsy, laparoscopy or via laparotomy.
● Cirrhosis may be difficult to confirm by needle
Classical signs
biopsy unless multiple sites are sampled. In practice,
● Anorexia, weight loss, lethargy and a small laparotomy incision and wedge biopsy of the
jaundice. liver gives a better diagnostic sample and is quick
● Hepatomegaly or a normal-sized liver may and simple. In cats with chronic hepatitis/cirrhosis,
be palpated. less than 40% of paired needle biopsy results may
be in accordance with the wedge biopsy diagnosis.
● Patients with cirrhosis may have occult bleeding
Pathogenesis tendencies. Screen for the presence of coagulopathy
prior to liver biopsy by performing evaluation of a
Cirrhosis is a relatively uncommon disease in the cat
PIVKA assay or APTT/OSPT.
but may occur as a progression of specific feline
hepatopathies (e.g cholangiohepatitis, chronic biliary
obstruction), systemic disorders (e.g., pancreatitis, Differential diagnosis
inflammatory bowel disease, chronic renal disease),
Cirrhosis is the end result of many different chronic
and possibly vascular and immune-mediated diseases.
liver disorders. Therefore, differentiation of the pri-
Cirrhosis would appear to occur most frequently with dis- mary parenchymal disease leading to cirrhosis is gener-
eases affecting the portal areas, specifically the bile ducts. ally not clinically relevant.

Cirrhosis is characterized by both fibrosis and the con-
version of normal hepatic architecture into structurally Treatment
abnormal (regenerative) nodules.
Strategies for therapeutic support in cats with cirrhosis
are first prioritized as to severity, and approached in a
Clinical signs logical step-wise fashion. The presence of jaundice or
ascites does not indicate a hopeless situation for med-
Anorexia, weight loss and lethargy predominate.
ical treatment.
Hepatomegaly and intermittent diarrhea may also be
Feed adequate calories (1.25–1.50 MER) to prevent
observed.
further malnourishment. Use of enteral nutrition is
Ascites is uncommon. strongly recommended in anorectic cats. Reduce
dietary protein intake in cats with overt signs of hepatic
Jaundice is often present.
encephalopathy (HE).
Supplement water-soluble vitamins as needed at
Diagnosis
twice the normal dose. Use vitamin K in cats with bil-
Cats usually have a previous diagnosis of chronic iary occlusion and elevated PIVKA or APTT/OSPT
hepatopathy, such as cholangitis (cholangitis/cholan- assays.
giohepatitis).
Control signs of HE with antimicrobials, reduced pro-
Liver enzyme activities are variably increased depend- tein diets and mucosal protectants (e.g., sucralfate).
ing upon the relative magnitude of cholestasis or hepa- Vitamin K therapy may reduce GI bleeding which also
tocellular inflammation. contributes to HE.