Lipid Droplet-Associated Proteins Perilipin 1 and 2: Molecular Markers of Steatosis and Microvesicular Steatotic Foci in Chronic Hepatitis C.

Chronic infection with hepatitis C (HCV) is a major risk factor in the development of cirrhosis and hepatocellular carcinoma. Lipid metabolism plays a major role in the replication and deposition of HCV at lipid droplets (LDs). We have demonstrated the importance of LD-associated proteins of the perilipin family in steatotic liver diseases. Using a large collection of 231 human liver biopsies with HCV, perilipins 1 and 2 have been localized to LDs of hepatocytes that correlate with the degree of steatosis and specific HCV genotypes, but not significantly with the HCV viral load. Perilipin 1- and 2-positive microvesicular steatotic foci were observed in 36% of HCV liver biopsies, and also in chronic hepatitis B, autoimmune hepatitis and mildly steatotic or normal livers, but less or none were observed in normal livers of younger patients. Microvesicular steatotic foci did not frequently overlap with glycogenotic/clear cell foci as determined by PAS stain in serial sections. Steatotic foci were detected in all liver zones with slight architectural disarrays, as demonstrated by immunohistochemical glutamine synthetase staining of zone three, but without elevated Ki67-proliferation rates. In conclusion, microvesicular steatotic foci are frequently found in chronic viral hepatitis, but the clinical significance of these foci is so far not clear.

Unveiling the unreal: Comprehensive imaging review of hepatic pseudolesions.

Hepatic pseudolesions are defined as non-neoplastic focal abnormalities of the liver which can mimic or conceal true liver lesions. It is particularly common in liver due to its unique dual blood supply and the existence of multilevel anastomosis between them. Because of the recent advances in CT and MRI technology, they are being increasingly encountered in daily practice. Broadly they can be categorised in to (1) Focal parenchymal abnormalities like focal fatty change, focal fat sparing, focal confluent fibrosis, segmental hypertrophy and regenerative nodules, (2) Perfusion abnormalities which include transient hepatic parenchymal enhancement in portal vein obstruction, third inflow, intrahepatic shunts, hepatic arterial occlusion and hepatic venous obstruction, (3) Imaging pitfalls like parenchymal compression, unenhanced vessels and pseudolipoma. It is essential for the radiologists to be familiar with the typical and atypical imaging features of pseudolesions to avoid mistaking them for sinister pathologies and also to avoid overlooking underlying hidden pathologies.

Fatty Liver / 대한간학회지

No abstract available.

Focal Fatty Change of the Liver

Focal fatty change of the liver is a nodular lesion which is a rarely described and poorly characterized entity. The hepatic nodule measured 1.4cm at its maximum diameter, was subcapsular in location and occurred adjacent to the falciform ligament. Microscopically it was composed of hepatic tissue with a preserved lobular architecture. The central venous structures and portal tracts with their triads were regularly placed. The cytoplasm of almost all of the hepatocytes within the nodule was replaced by macrovesicular fat vacuoles with the nuclei displaced. Several large abnormal vessels were found at the margin of the nodule. The nodule was discovered incidentally on postmortem examination of a female infant who proved, at autopsy, to have multiple cardiac anomalies and bronchopneumonia. The possible inadequate local tissue perfusion due to abnormal intrahepatic vessels at this particular location could be augmented by multiple cardiac anomalies culminating in focal ischemia and focal fatty change. When encountered in surgery or on gross examination, it could be confused with other space occupying lesions such as liver cell adenoma, abscess and metastatic lesions.