Congenital Dilatation of the Bile Ducts (Caroli’s Disease) in Young Dogs

Abstract

We describe 8 young dogs with congenital dilatation of the intra- and extrahepatic bile ducts and diffuse cystic kidney disease, compatible with Caroli's disease in humans. The dogs were referred between 1980 and 2000 because of chronic disease at an age of 6 months to 3 years. These dogs included 3 Collies, 2 Frisian Stabyhouns, 2 Jack Russell Terriers, and 1 mixed-breed dog. The most common signs were vomiting (6/6), polyuria and polydipsia (4/6), and anorexia (4/6). Ascites was a common finding (4/6). Clinicopathologic abnormalities were available for 6 dogs. All had increased plasma alkaline phosphatase activity and fasting bile acids: increased alanine aminotransferase activity and urea and creatinine concentrations were present in 50% of dogs. Ultrasound examination of the liver showed severely dilated bile ducts without evidence of obstruction, and calcification in all cases but 1. Postmortem examination revealed severe dilatation of the larger intra- and extrahepatic bile ducts. The common bile duct and gall bladder were normal, and the bile system was patent. The ducts contained a clear viscid fluid often with calcified material. Microscopically, marked portal fibrosis was present, often with abnormally structured dilated bile ducts lined with columnar or cuboid epithelium and regularly small calcifications. The lesion was complicated by ascending cholangitis in 1 dog. The kidneys showed marked cortical and medullary fibrosis with a diffuse radial cystic pattern; only slight renal fibrosis was found in the oldest dog. Seven dogs were euthanized without treatment; the oldest dog was alive and well 5 months after diagnosis and was maintained on a protein-restricted diet.

Morphological classification of biliary disorders of the canine and feline liver

“…6,9 Although often not clearly defined with regard to inheritance, similar morphological entities can be discriminated in dogs and cats. 13,14 As in humankind, in Persian cats and Persian crossbreeds with polycystic kidney disease (Fig. 5.10).…”

Urinary Tract

“…Multiple parenchymal cystic areas are present at birth enlarge with maturity and may cause significant loss of renal function, depending on the number and volume of cystic change. 39,[55][56][57] Two cats with renal polycystic disease were also reported to have concurrent hepatic cysts, but their locations were not discussed. 54 While an accurate genetic test is available for the autosomal dominant genome, it cannot predict severity or progression of polycystic disease over time.…”

Liver

“…48 Target lesions have a hypoechoic rim with an isoechoic or hyperechoic center (see Figure 9-9, A). [56][57][58] The kidneys should always be evaluated because polycystic renal disease may accompany hepatic cysts in both the dog and cat. 47 Clinical experience indicates that nodular hyperplasia may appear similar to some forms of vacuolar hepatopathy and extramedullary hematopoiesis.…”

“…A target lesion is an uncommon finding with nodular hyperplasia and is more often associated with neoplasia. 54,55,[57][58][59][60][61] Careful scanning sometimes suggests communication of the cystlike structure with the biliary tract if localized ductal ectasia is present. When larger, nodular hyperplasia may resemble hematomas, abscesses, necrosis, and primary or metastatic liver neoplasia.…”

“…Two types of bilobed gallbladders have been described. 57,58 This disorder generally causes saccular biliary ductal dilatation and may predispose the patient to bacterial cholangitis and stone formation. This type appears normal when viewed externally.…”