Today’s lecture primed us on the basics of hepatopathology that every hepatologist should be familiar with. We started with distinguishing acute from chronic liver injury. The acute injury pattern will be associated with inflammation in zones 2 and 3 and edema/ballooning can be seen. More chronic injury will be associated with inflammation limited to zone 1, the portal triad and its periportal hepatocytes.
The second topic was recognizing the various injury patterns relative to specific types of disease. The hepatitic pattern (HBV, HCV, autoimmune hepatitis) is centered around zone 1. The toxic/metabolic pattern (NASH, ASH, Wilson) is out in the lobule, zone 2, with a sinusoidal pattern of fibrosis. The drug injury pattern (DILI) can mimic anything, but is often seen near zone 3, the central vein, because this is where many of the metabolism enzymes are concentrated. In addition, the ischemic-type injury occurs here because the partial pressure of oxygen is lowest in zone 3.
Lastly, time was spent discussing the common occurences of injury in the transplanted liver. We are familiar with acute cellular rejection, denoted by the triad of mixed inflammation, endothelialitis and cholangiolitis. Chronic rejection is noted by ductopenia and a foamy arteriopathy near the central vein.