Centrizonal necrosis of liver occurs with -a) Carbon tetrachloride (CC14) toxicityb) Heart failure (CHF)c) Smoking (chronic)d) Chronic alcoholism
Hepatocellular necrosis: -

Liver necrosis is a common manifestation of many liver diseases and it can present in various ways.
If severe it can cause liver failure.
In some cases however the necrosis is subclinical, revealed only by elevations of liver enzymes in serum.
Various diseases can cause different patterns of necrosis. These are —

Focal Necrosis -
Randomly occurring necrosis of single cells or small clusters of cells.
It can involve any area of the lobule
All lobules are not involved.

Characteristic features on biopsy are -

Councilman bodies
Areas of lysed liver cells surrounded by collection of kupffer cells and inflammatory cells.

Causes of Focal necrosis -
Viral hepatitis, Bacterial infections, Toxic damage
Zonal necrosis -
The characteristic of zonal necrosis is that identical regions of liver lobules are involved.
All liver lobules are involved.
The necrosis is divided according to the zone involved
(Note: In focal necrosis any area of lobule and some lobules are involved.)

Types of zonal necrosis
(a) Centrizonal necrosis (centrilobular) → Necrosis in the cells surrounding central hepatic vein, seen in -

Cardiac failure or shock     
Carbon tetrachloride toxicity (CC14) 
Chloroform toxicity
Viral hepatities

(b) Peripheral zonal necrosis (periportal) → Necrosis is seen in areas around the portal tracts, Seen in
(i) Eclampsia                
(ii) Phosphorus poisoning
(c) Midzonal necrosis → Rare, seen in yellow fever

Also know —

Submassive necrosis → Occurrence of liver cell necrosis that is not limited by lobular boundaries i.e., the necrosis extends beyond lobular boundaries.
Massive liver necrosis → In this large areas of liver cell undergo necrosis. Only small areas are left intact.
Massive and submassive liver necrosis are clinically manifested as.
	Acute liver failure of variable severity  
	Serum enzyme levels are very high
ac
ab
ad
bc