Important Features of Acquired and Congenital Hepatobiliary Disorders
––––--ACQUIRED--------- | ––––-CONGENITAL--------- | ||||
|---|---|---|---|---|---|
Early signs | Major bile duct occlusion | Severe hepatic insufficiency | PSVA, PSS | Microvascular dysplasiaa (no PSVA, microscopic shunting) | Ductal plate malformation |
Vomiting | ± Vomiting | ± Vomiting | Abnormal behavior: lethargic | Liver ± small, low normal | Liver ± small, low normal size |
Diarrhea/constipation | ± Diarrhea/constipation | ± Diarrhea/constipation | ± Diarrhea/constipation | No clinicopathologic markers except ↑↑↑ bile acids | ± Liver lobe hypoplasia |
Weight loss | Weight loss | Weight loss | Weight loss | ± Gallbladder atresia/hypoplasia | |
Pyrexia | Pyrexia | ± Pyrexia | ± Pyrexia | Protein C: normal (usually) | Predisposed to cholangitis |
“Noisy enzymes” | Polydipsia | Polyuria/polydipsia | Polyuria/polydipsia | No hepatic encephalopathy | ± Pyrexia if cholangitis |
Normal bilirubinemia | Jaundice within 72 hours | Jaundice as disease advances | No jaundice | Variable liver enzymes: most common ↑ ALT, ↑ALP with inflammatory bowel disease | Variable enzymes: ↑ ALT, ↑ ALP ↑ with inflammatory bowel disease |
Clear to yellow urine | ↑ ALP & GGT | Variable ↑ ALP, AST, ALP, GGT | ↓ RBC, MCV, ↓ BUN, ↓ creatinine | ||
Normal bile acids | ↑ ALT & AST, ↑ cholesterol | Gradual decline in cholesterol ↓ cholesterol | Variable liver enzymes ↓ cholesterol | No jaundice unless severe cholangitis | |
Polyuria/polydipsia | Orange urine ± neg urobilinogen: unreliable | Clear to orange urine urobilinogen "+" ↑↑↑ bile acids bruising/bleeding tendencies | Ammonium biurate crystalluria Normal coagulation ↑↑↑ bile acids | No ammonium biurate crystalluria unless acquired portosystemic shunts form secondary to congenital hepatic fibrosis Rarely dogs have PSVA—no ascites | |
Bleeding tendencies: 7–10 days | Brown to melenic feces | ↓ Protein C (< 70%) often | |||
Acholic (pale) feces | Brown feces | Copper-colored iris: cats | |||
Melenic feces if GI bleeding | Green feces: ↑ stercobilin | Typically no ascites | |||
Gastrointestinal ulceration | Normal to microhepatica: dog | Young dogs: melena—parasites | |||
Hepatomegaly: firm; rounded borders | Hepatomegaly: cat | Microhepatica with “plump” kidneys | |||
Palpable gallbladder: cat if chronic: > 6 weeks ascites edema (rare in cats) | Gastroduodenal ulceration associated with portal hypertension ascites if: portal hypertension ascites if: portal hypertension: ↓ albumin fosters ascites acquired portosystemic shunts | ± Cryptorchid (small-breed dogs) ptyalism (cats) rare gastrointestinal ulceration: ↑ risk for hepatic encephalopathy portal hypertension: only if intolerant to shunt ligation, true portal atresia, or arteriovenous malformation ascites rare unless portal vein atresia or hepatic arteriovenous fistula edema does not occur | |||
HE: variable stupor, lethargy, depression pacing, head pressing rarely coma, seizures hyperammonemia: usually coincides with HE signs ammonium biurate crystalluria cystic/renal calculi urinary tract obstruction pollakiuria: urinary calculi | HE: common tooth eruption bleeding →↑ risk HE GI bleeding: parasites →↑ risk HE amaurosis, stupor, depression, head pressing pacing, aggression (esp cats), ptyalism seizures with prolonged prodrome hyperammonemia: usually coincides with HE ammonium biurate crystalluria: common with HE | ||||
Ammonium urate cystic calculi: less common renal calculi may present for urinary obstruction →↑ BUN → NH3 →↑ risk HE hematuria: due to urinary bladder calculi | |||||
aDoes not limit lifespan PSVA, portosystemic vascular anomaly. PSS, portosystemic shunt. ALP, alkaline phosphatase. GGT, gamma glutamyl transferase. MCV, mean corpuscular volume. HE, hepatic encephalopathy. | |||||