Page 926 - Cote clinical veterinary advisor dogs and cats 4th

454 Hepatitis (Chronic, Idiopathic) of Dogs

10-15 mg/kg q 12h can be given alone PO q 12h or combination of both drugs Recommended Monitoring
or in combination with glucocorticoids. ○ Abdominal drainage can be performed • Monitor general condition, body weight,
should be considered.
VetBooks.ir kg q 12h, tapering to 5 mg/kg PO q intermittently as needed for comfort when • Periodic evaluation of laboratory tests (CBC,
○ Cyclosporine (author’s preference) 5 mg/
and behavior.
24h with improvement can be given for
serum biochemical profile)
patients develop tense ascites (very large
immunosuppression without the need
for glucocorticoids and with potentially volumes of abdominal fluid). Caution is • Follow-up liver biopsy provides the best
advised because abdominocentesis may
means of evaluating treatment response for
fewer side effects than azathioprine or result in hypovolemia and protein loss. amount of ongoing inflammation and hepatic
mycophenolate. copper concentrations.
○ Corticosteroids or immunosuppressive Nutrition/Diet
therapy appears to prolong survival or • Palatability is important in advanced cases PROGNOSIS & OUTCOME
resolve hepatitis, although large case because adequate caloric intake is crucial.
studies are lacking. • Avoid protein restriction unless HE is • Guarded to fair based on clinical signs at the
• Copper chelation if hepatic copper concentra- present. Dietary protein content should time of diagnosis and extent of liver damage
tions are > 600-1000 mcg/g dry liver weight represent 18%-22% of digestible kcal/day. • Early diagnosis and therapy can prolong
(p. 458) Feed a high-quality, moderate-protein diet survival, but limited studies are available on
• If there is deficiency in advanced disease, zinc given in small multiple feedings. Milk and survival times (cirrhosis 1-2 months; chronic
gluconate 2-3 mg/kg PO q 24h is indicated. vegetable protein sources are more beneficial hepatitis several months to years).
Higher doses of zinc block intestinal copper in HE than meat protein–based diets. • Most dogs are diagnosed when clinical signs
absorption and could be considered after • Fermentable fiber may also be beneficial in occur, which are usually associated with more
copper chelation therapy. controlling HE. advanced hepatitis and a guarded prognosis.
• Ursodeoxycholic acid 10-15 mg/kg PO q 24h • Specialty veterinary hepatic diets are low in • By the time liver failure manifests (e.g.,
is a hydrophilic bile acid that has immuno- copper and prevent hepatic copper accumula- ascites, HE, hypoalbuminemia), the prog-
modulatory, antioxidant, hepatoprotective, tion. These diets are also rich in antioxidants nosis is grave.
and choleretic effects. Although widely used and other liver-support ingredients.
for canine hepatopathy, strong evidence of PEARLS & CONSIDERATIONS
efficacy is lacking. Drug Interactions
• Antioxidant therapy is used because oxidative • Avoid drugs that require hepatic metabolism Comments
damage is shown to occur in many dogs with or alter hepatic biotransformation (e.g., • The first clue to chronic hepatitis is unex-
hepatic disease. Selection of one or several cimetidine), and avoid drugs with known plained abnormal serum liver enzyme activi-
antioxidants is suggested, including vitamin risk for hepatotoxicity (e.g., phenobarbital). ties (increased ALT is especially concerning).
E 10 IU/kg PO q 24h, S-adenosylmethionine • Glucocorticoids may cause sodium retention, • Because of the great reserve capacity of the
(SAMe) 20 mg/kg PO q 24h or q 48h, promote GI ulceration, or precipitate hepatic liver, signs of liver failure do not occur until
or milk thistle (silybin complexed with failure with advanced disease. Glucocorticoids the disease is advanced.
phosphatidylcholine) 24-70 mg/kg/day. also result in a vacuolar (steroid) hepatopathy, • Immunomodulatory therapy in early stages
Commercial products (e.g., Denamarin, making laboratory evaluation of treatment of hepatitis may prolong survival.
Nutramax Laboratories) combine multiple response difficult.
antioxidants. • Penicillamine and zinc should not be given Technician Tips
• Antibiotics are used to modify GI bacterial together; penicillamine can chelate zinc. • Ensure patients intended for bile acid panel
flora in HE, treat or reduce the incidence • Animals with hepatic failure are anesthetic testing, abdominal imaging, and liver biopsy
of secondary infection, or to treat a primary risks. Barbiturates should be avoided, are fasted for 12 hours.
pathogen (e.g., Leptospira). and benzodiazepines should be used with • After liver biopsy, the patient must be
• The mainstay of antifibrotic therapy is care. Isoflurane or sevoflurane are the gas monitored closely for bleeding, including
reducing inflammation. Although colchicine anesthetics of choice. Propofol, although obtaining a packed cell volume/total solids
0.03 mg/kg PO q 24h inhibits collagen metabolized in the liver, is generally safe (PCV/TS) evaluation 3 and 6 hours after
formation, few studies report its use in dogs, when administered to effect (usually requir- biopsy.
and human studies fail to show prolonged ing a small fraction of usual dosages).
survival. Angiotensin-receptor blockers • Lidocaine, theophylline, propranolol, cap- Client Education
have shown promise in inhibiting fibrosis topril, and tetracyclines should be avoided. • A complete cure is unlikely.
in humans and may have an application in • Diuretics may worsen HE, promote dehydra- • Medication is generally lifelong but may
dogs (e.g., telmisartan 0.5-1 mg/kg PO q tion or metabolic alkalosis and should be prolong quality of life and survival time.
12h), although studies on safety and efficacy used only in otherwise stable patients for • Repeat liver biopsies are recommended to
are lacking. Phosphatidylcholine 20-70 mg/ the long-term delay of return of ascites or monitor response to therapy.
kg/day PO may also have antifibrotic if necessary for concurrent conditions (e.g.,
effects but has not been studied in this congestive heart failure). SUGGESTED READING
setting. • NSAIDs may exacerbate GI ulceration. Bexfield N: Canine idiopathic chronic hepatitis. Vet
• Ascites Clin North Am Small Anim Pract 47:645-663,
○ Medical treatment involves diuretics Possible Complications 2017.
for long-term chronic management. Ascites, HE, GI ulceration, sepsis, and AUTHOR: David C. Twedt, DVM, DACVIM
Spironolactone 0.5-1 mg/kg PO q 12h disseminated intravascular coagulation are EDITOR: Keith P. Richter, DVM, MSEL, DACVIM
is suggested as the initial diuretic. If ascites potential complications and are grave prognostic
is not controlled, furosemide 0.5-2 mg/kg indicators.

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