Hepatology refers to the study of the diseases affecting the liver, gallbladder, bile ducts and pancreas. Occasionally, diseases affecting other organs can affect the hepatobiliary system.
Although the most common causes for liver disease are viral infections, such as hepatitis B and hepatitis C, and alcohol, there are many different diseases, often genetic or hereditary, that can result in liver damage.
Liver eznymes, such as ALT, AST, ALP and GGT are raised in the setting of either hepatocyte inflammation (the former two tests), biliary obstruction (the latter two tests), or both. Liver function tests, such as bilirubin, INR, and albumin, are those tests that measure the synthetic and excretory capacity of the liver. Occasionally we use the platelet count as another marker of liver function, as in patients with liver disease, a low platelet count (ie
The majority of patients with liver disease will not have symptoms until they have end-stage liver disease, or if they have an acute injury to their liver. Thus, most patients presenting to the hepatology clinic will feel completely fine. Symptoms that are suggestive of liver disease are yellowing of the skin or the whites of the eyes, right sided stomach pain, increasing abdominal girth, ankle swelling, or, in severe cases, confusion and excessive sleepiness (ie features of decompensated liver disease). Patients with an acute hepatitis may present asymptomatically, or with jaundice, myalgias and right upper quadrant abdominal pain. The term “hepatitis” simply refers to an inflammation of the liver, and does not specify cause (ie viral hepatitis vs autoimmune vs drug related, etc).
Occasionally patients may develop masses in the liver. Although these can be cancer, there are a number of benign (ie non-cancerous) masses that can develop in a healthy patient. Some of benign masses arising in the liver are adenomas, focal nodular hyperplasia, and hemangiomas. Please refer to the liver tumour section for further details about these.
Causes of Liver Disease:
- Medications: Prescription, over the counter, and herbal medications can all result in liver damage if not taken with caution. In addition, some medications (both prescription and herbal) may interact with other medications to result in liver disease.
- Infectious: Viral hepatitis (hepatitis A, B, C, D and E; EBV, CMV, HSV); parasitic liver infections
- Genetic: Non-alcoholic fatty liver disease (NAFLD), hemochromatosis (iron overload), Wilson disease (copper overload), alpha-1-antitrypsin deficiency.
- Autoimmune: Autoimmune diseases are diseases wherein the body itself starts attacking various parts of the liver. Examples of autoimmune diseases are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Although these are often thought to have an inherited component, they are not tied to any known gene or genetic mutation at this time.
- Other: Heart failure; clots in the vessels leading into or out of the liver.