Background: Portal hypertension is a clinical syndrome that manifests as ascites, portosystemic encephalopathy and variceal hemorrhage, and these alterations often lead to death.

A new model of extrahepatic cholestasis, using a microsurgical technique, is performed as an alternative to the traditional model of the bile duct ligated-rat, in order to study the stage of fibrosis in the long-term. Male Wistar rats were divided into two groups: I (Sham-operated, n = 9) and II [Microsurgical Cholestasis (MC), n = 10]. After 4 weeks, portal pressure, types of portosystemic collateral circulation, mesenteric venous vasculopathy, hepatic function test, and liver histopathology were studied by using the Knodell index and fibrosis was determined by reticulin and Sirius red stains. The animals with MC presented portal hypertension with extrahepatic portosistemic collateral circulation, associated with mesenteric venous vasculopathy and increased plasma levels of bilirubin (6.30 +/- 1.80 vs. 0.22 +/- 0.37 mg/dL; P = 0.0001), alkaline phosphatase (293.00 +/- 82.40 vs. 126.30 +/- 33.42 U/L; P = 0.001), AST (380.00 +/- 78.50 vs. 68.33 +/- 11.74 IU/L; P = 0.0001), ALT (87.60 +/- 22.32 vs. 42.22 +/- 7.89 IU/L; P = 0.0001), and LDH (697.76 +/- 75.13 vs. 384.80 +/- 100.03 IU/L; P = 0.0001). On the contrary, plasma levels of albumin decreased (2.72 +/- 0.12 mg/dl vs. 2.99 +/- 0.10; P = 0.001). The microsurgical resection of the extrahepatic biliary tract in the rat produces an experimental model of hepatic inflammation, characterized by a high Knodell hepatic activity index (4), bile proliferation, and fibrosis.

Fibrosis, bile duct proliferation and mast cell hyperplasia characterize extrahepatic cholestasis. We studied these liver alterations in a new microsurgical model of extrahepatic cholestasis in the rat. Male Wistar rats: Sham-operated (n=9) and Microsurgical Cholestasis (n=10). After 4 weeks, a liver morphometric study was carried out using an image analysis system to assess bile proliferation and the fibrosis. The liver expression of alpha-smooth muscle actin was assayed by an immunohistochemical technique and mast cells were also counted. Cholestatic-rats presented portal hypertension, portosystemic circulation, and increased (p=0.0001) plasma bilirubin, alkaline phosphatase, Aspartateaminotransferase, Alanine-aminotransferase, and Lactate-dehydrogenase. Plasma levels of Albumin decreased (p=0.001). Cholestatic-rats showed intense biliary duct proliferation (p=0.0001) and fibrosis (p=0.0001). Mast cells accumulate (p=0.0001) around proliferating bile ducts and fibrous septa. The microsurgical cholestasis in the rat induces fibrosis and hyperplasia of bile ducts and mast cells. Mast cell liver infiltration could be an etiopathogenic remodeling factor in experimental cholestasis.

Cholangitis lenta, also known as ductular cholestasis, cholangiolar cholestasis, or subacute nonsuppurative cholangitis, is an uncommon type of cholangitis characterized by ductular reaction with inspissated bile in dilated ductules. The literature on this unique entity has been limited to only a few studies based on a very limited number of cases, which importantly suggest an association with sepsis and/or intra-abdominal infection. The clinical, laboratory, and histologic features of 28 cases of cholangitis lenta are herein investigated. Twenty-five (89.3%) patients were liver transplant recipients. Most notably, the majority of patients showed clinical signs and symptoms of sepsis, and positive microbiology cultures were demonstrated in 24 (85.7%) patients. Significantly, 15 (53.6%) patients died during their hospitalization, ranging from 2 days to 5 months after the initial liver biopsy that showed histologic features of cholangitis lenta. Among the 13 discharged patients, including 2 who received retransplantation, 4 (14.3%) subsequently died of pneumonia, graft dysfunction, or fungal infection within 7 months to 9.3 years. Only 9 (32.1%) patients were alive at the last follow-up, with the follow-up time ranging from 3.8 to 10.4 years. Our data show that the finding of cholangitis lenta on liver biopsy is thus frequently associated with sepsis and with a high mortality rate. Therefore, accurate diagnosis of this condition on liver biopsy is imperative as it is an indication that the patient may have a potentially life threatening condition that requires immediate medical attention and management.