Cirrhosis is a late-stage liver disease where healthy liver tissue is gradually replaced with scar tissue (fibrosis), blocking the flow of blood through the liver, thereby interrupting liver function. It is a progressive disease that develops slowly over years which if left untreated, the scar tissue build-up can permanently damage the liver or eventually stop the liver to function altogether.
Cirrhosis is caused by many forms of liver diseases and conditions, such as hepatitis and excessive alcohol consumption or liver injury where the liver is prompted to repair itself by forming scar tissues. The damage done by cirrhosis generally can't be undone, and late-stage cirrhosis, in particular, can be life-threatening. However, if liver cirrhosis is diagnosed early and the cause is treated, further damage can be limited and, rarely, reversed.