All about liver

Hepatitis B vaccination

Hepatitis B is one of the common causes of chronic liver disease. It can be prevented by hepatitis B vaccination. The vaccines are easily available at hospitals. Three doses are required to achieve adequate antibody levels. Booster doses may be required at intervals to maintain adequate antibody levels in the blood. 

Common liver diseases

Alcoholic liver disease

Long-term alcohol consumption can cause spectrum of liver disease ranging from fatty liver, steatohepatitis (inflammation of liver cells due to fat infiltration), fibrosis, cirrhosis, to development of liver cancers (hepatocellular carcinoma). 

Alcoholic liver disease is the leading cause of liver cirrhosis in the world. Alcohol is metabolized to acetaldehyde in liver. It is a toxic compound and plays a key role in development of alcohol-related liver disease. Other important mechanisms are oxidative stress, molecular changes, hypoxia, and others. With timely lifestyle changes and abstinence from alcohol, most of the harmful changes can be reversed. In advanced disease, one may require medicines and liver transplant. 

Fatty liver

Fatty liver is a condition where excess fat builds up in the liver. It is also known as hepatic steatosis. It is commonly associated with diabetes mellitus, obesity and dyslipidemias like hypercholesterolemia and hypertriglyceridemia. 

Non-Alcoholic Fatty Liver Disease (NAFLD) is a broad term, encompassing a spectrum of fatty liver disease from fatty liver to steatohepatitis to liver cirrhosis. It is categorized in NAFL (Non-Alcoholic Fatty Liver) and NASH (Non-Alcoholic Steatohepatitis). NAFL is a condition where there is 5% or more fat deposition in liver without liver cell injury. NASH is a condition, characterized by 5% or more fat deposition in liver with inflammation and liver cell injury with or without fibrosis. 

The incidence of fatty liver disease is rising in the general population worldwide and it is now one of the common causes of liver cirrhosis. The prevalence of NAFLD in general population worldwide is estimated to be approx. 20-30%. The prevalence of NASH in general population is estimated to be approx. 1.5-6%. The increasing incidence of fatty liver disease is partly due to sedentary lifestyle, increasing prevalence of diabetes mellitus and unhealthy food habits. The treatment of fatty liver revolves around weight control, strict diabetes control (in diabetic patients) and treatment of dyslipidemias like hypercholesterolemia and hypertriglyceridemia. Once liver cirrhosis sets in, patient may require liver transplantation. 

Viral hepatitis

Viral hepatitis is another common cause of liver disease. It may be caused by Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis D or Hepatitis E viruses. Hepatitis A and Hepatitis E spread by contaminated water and unhygienic food. Hepatitis B and Hepatitis C spread by contaminated blood, body fluids, and unprotected sexual practices. Hepatitis A and Hepatitis E are generally self-limiting diseases. They may however sometimes cause acute liver failure, which is a life-threatening condition. Hepatitis B and Hepatitis C, when present for a long duration may cause liver cirrhosis and liver cancers. Such patients may require liver transplantation. 

Autoimmune hepatitis

Autoimmune hepatitis is a disease of unknown cause, characterized by presence of autoantibodies against one’s own liver cells. It may present with non-specific symptoms. It may sometimes present with acute liver failure, which is a life-threatening condition.  It is usually diagnosed by deranged liver function tests, positive autoantibodies in blood, and liver biopsy. The mainstay treatment is steroids. Patients with acute liver failure or autoimmune liver cirrhosis may require liver transplantation. 

Liver cancers

Hepatocellular carcinoma (HCC) is the commonest primary liver cancer. Secondary liver cancers include tumor spread from colon and rectal cancers, neuroendocrine tumors, stromal tumors, and tumor spread from other primary cancers in the body. Patients may have a spectrum ranging from non-specific symptoms to jaundice, weight loss, loss of appetite, and others. The diagnosis is by blood tests and imaging in form of ultrasonography, CT scan, MRI and/or PET scan. Treatment depends on the nature and biology of cancers and may range from liver resection, liver transplantation, to chemotherapy and radiotherapy. 

Acute liver failure

Acute liver failure is a condition wherein a patient presents with signs of liver failure and altered sensorium in an acute setting, usually without any history of pre-existing liver disease. Common causes of ALF are paracetamol poisoning, drug induced liver injury (e.g., Anti-tuberculosis treatment), viral hepatitis – commonly Acute hepatitis A, B or E, alcoholic liver disease, Wilson disease, acute autoimmune hepatitis, and others. Some poisons like Ratol (yellow phosphorus) can also cause acute liver failure. Acute ischemia due to shock and acute fatty liver of pregnancy can also lead to ALF. Some other diseases like Dengue and Leptospirosis are also known to cause ALF. The treatment of ALF consists of medical management and liver transplantation. 

Liver tests 

Blood tests

The blood tests that are commonly performed to evaluate a patient with liver disease are liver function tests, complete blood count, renal function tests and others. Some diseases may warrant blood tests like tumor markers – Alpha feto protein (AFP), Carcinoembryonic Antigen (CEA), and Carbohydrate Antigen (CA 19-9) 

Radiology

Radiological tests which are commonly used to evaluate a patient are abdominal ultrasonography, CT scan and MRI. Some diseases may warrant other tests like PET scan and HIDA scan. 

Other tests

Upper GI endoscopy is commonly performed in liver cirrhosis patients. Other tests like liver biopsy may be required for evaluation of some liver diseases.