|Path Labs||CTools||Lab Instructors||ImageScope||Histology Normals||Histology Site||M1 Histopathology|
GI Path Lab 3: Part II
Reading Assignments (Robbins: Pathologic Basis of Disease, 8th Ed.)
|835 - 836||Morphology of hepatic injury|
|857 - 861||Morphology of fatty liver, including non-alcoholic fatty liver disease|
|870 - 873||Circulatory disorders through hepatic vein thrombosis|
|843 - 856||Morphology of acute viral hepatitis and chronic hepatitides|
|850 - 853||Submassive to massive necrosis|
|867 - 869||Primary biliary cirrhosis and primary sclerosing cholangitis|
|837 - 838||Cirrhosis (introduction)|
|857 - 860||Alcoholic liver disease. Skip the clinical stuff and get it from the Medicine book.|
|861 - 864||Hemochromatosis and Wilsonís disease as cirrhoses|
|875 - 882||Tumors of the liver|
Areas of Concentration
Upon completion of this exercise, you should be able to:
ACUTE LIVER DISEASE
Acute Ischemic Liver Disease (Central Hemorrhagic Necrosis)
On low power examination of this section, viable-looking liver cells are found in a predictable location, namely, around the portal tracts. In contrast, there are hemorrhagic areas around the central veins. Some of these areas contain only blood; others contain ghosts of hepatocyte cords in addition to the blood, while still others contain mainly necrotic hepatocytes and little blood. This is the essence of a zonal injury that has caused confluent necrosis, in this case, confluent central necrosis with blood, or central hemorrhagic necrosis.
This is an example of a cellular alteration, sometimes, but not always, an injury, but generally reversible. Normal hepatocytes contain lipid, but not in large clumps that are seen in routine light microscopy. Fatty livers of mild degree are very common. Fatty livers of severe degree indicate a profound metabolic imbalance.
The dominant change is the presence of brown or brownish-green pigment that is mainly found between liver cells. On occasions, the brown pigment forms long and even branched structures. This appearance indicates that the material is within the bile canaliculi between hepatocytes. Remember, bile canaliculi are tubes or channels for bile flow which are formed by specialized parts of cell membranes of adjacent liver cells. Cholestasis is defined simply as interference with bile flow. Cholestasis is a common accompaniment of many liver diseases. Therefore, it is more like a sign or symptom of liver disease, rather than a disease by itself.
Acute Viral Hepatitis
Most of the liver cells are pale and rounded, creating disorganized cords. Scattered about are necrotic liver cells with dark red cytoplasm and either no nucleus or fragments of a nucleus. Scattered about also are slightly granular, pale yellow-brown phagocytes similar to those in the central zones in Slide 32, which contain necrotic liver cell debris. In some places, it appears as if whole clusters of hepatocytes have disappeared. The portal tracts contain inflammatory cells, mostly lymphocytes, and scattered lymphocytes are present within the sinusoids. This is a characteristic picture of the peak phase of an active, intense hepatitis, such as might be caused by one of the hepatitis viruses. Occasionally, drugs or poisons can cause a similar process.
The answers to the path lab questions will be posted approximately 48-72 hours after the lab sessions. These are abbreviated answers, not a full discussion of the topics. You can find them in the M2 CTools site resources. In the folder for each sequence the will be a folder called 'Path Lab Resources'