Liver Disease

What is liver disease?

The liver is one of the largest solid organs of the body. It is located in the upper right part of the abdomen. Most of the organ lies under cover of the rib cage.

Liver function

It is not just the liver’s size but also its functions that makes it so important.

Its major functions include processing the food that passes through the gut and converting it into energy that can be utilized by the body.

It is also a powerful detoxification center that handles many chemicals, alcohol, poisons and toxins as well as drugs and clears the blood.

The liver also makes bile and stores it in a small pouch like organ called the gall bladder. This bile helps in digestion especially fats.

Liver anatomy

The liver is divided into two major lobes that are further divided into lobules.

The liver gets blood supply fresh from the heart via the hepatic artery. It also receives blood from the portal vein that brings in blood rich in nutrients carried in from the gut or intestines.

The blood from the portal vein undergoes “offloading” of nutrients and “cleansing” of toxins at the liver.

Liver helps processing or metabolizing nutrients like glucose, cholesterol, drugs, stores iron etc.

Liver is one of the only organs in the human body that can regenerate its own damaged tissues. However with repeated damage and constant injury the liver may fail to perform its functions leading to liver failure. Liver failure may sometimes even be fatal. (1)

Causes of liver disease

Liver diseases may vary in causation.

They may be of short duration, acute liver disease, or long term, chronic liver disease. An acute liver disease may also convert into a chronic liver disease over time.

Some liver diseases are caused by infective viruses like Hepatitis virus (A, B and C).

Liver diseases also result from taking in some drugs or alcohol over long term. Sometimes the diseased liver over long term becomes shrunken and scarred.

Such a condition is called cirrhosis. Like other organs liver can also be afflicted with cancers. (2)

Types of liver disease

Alcohol related liver disease is one of the commonest toxin induced liver disease worldwide. In normal cases the liver breaks down alcohol in the body.

If there is too much intake over a long period of time the liver fails to perform its functions leading to a condition called Alcoholic Liver disease.

Alcohol-related liver disease may be of three types – fatty liver disease, alcoholic hepatitis and finally alcoholic cirrhosis.

The alcohol related liver disease begins as fatty deposits on the liver followed by inflammatory changes and finally irreversible tissue scarring or cirrhosis.

The hepatitis phase leads to swelling of the liver and damage. At the initial phases of alcohol liver disease if alcohol is discontinued the changes may be reversed. (3)

Liver disease may also be Non-Alcoholic called Non Alcoholic Fatty Liver Disease. This results in fat deposits on the liver and is seen in obese, diabetic and individuals with high blood cholesterol. It can affect 2-5% of the general population. (4)

Liver disease is thus a wide ranging term that includes all conditions that cause imbalance or disturbance of the functions of the liver.

Liver disease is also called hepatic disease. Since it is a large organ, nearly two thirds of the liver has to be affected for the symptoms of hepatic disease to show in most individuals.

If there is very high blood pressure in the portal vein the condition is termed portal hypertension. This can lead to cirrhosis, enlarged abdomen with fluid (ascitis), bleeding, enlarged spleen, and sometimes jaundice. Bleeding may occur in the esophagus or via rectum.

Portal hypertension is often a result of liver cirrhosis that results from chronic liver disease.

Portal hypertension may also sometimes lead to a condition called hepatic encephalopathy where the brain is affected and the person may go into coma. This is usually accompanied by liver failure. (5)

Edited by April Cashin-Garbutt, BA Hons (Cantab)

Causes of liver disease

The liver functions by clearing the body of drugs toxins and poisons and metabolizing nutrients for use. When the liver is damaged in the short or long term due to infection or other causes there may be liver disease.

Classification of liver disease based on causes

To divide causes of liver disease based on the basic pathology we can classify them as drug or toxin induced; infective; and metabolic or other causes (1, 2, 3) : –

  1. Drug or toxin induced –
    1. Alcohol related liver disease – Those who take too much alcohol over long periods of time risk the health of their liver. Initially the liver cells swell up and there may be fat deposits. The condition is called alcoholic fatty liver. Thereafter the liver as a whole is inflammed and swollen, which gives rise to alcoholic hepatitis. Finally there is scarring leading to liver cirrhosis. The liver loses its ability to function and may fail which can be fatal.
    2. Drug induced liver damage – Some medicines may also damage the liver. These may range from common drugs like acetaminophen (fever remedy) that may lead to liver failure in overdoses. Some drugs that lower cholesterol like Statins and Niacin also damage the liver. Other liver damaging drugs include nitrofurantoin, tetracycline, isoniazid (antibiotics) or Methotrexate (anti-cancer drug). Some herbal drugs also damage the liver. These include kava kava, ma huang etc. Many mushrooms can also cause severe liver damage.
  2. Infective -
    1. Hepatitis A virus – This virus is transmitted via faeces and contaminated water. Although it leads to an acute liver damage, in some individuals it may lead to long term liver disease. Acute liver damage may manifest as jaundice, fever, nausea and vomiting. Although mild, this condition may lead to severe damage and even liver failure.
    2. Hepatitis B and C virus are spread via infected blood transfusion, contaminated needles and other body fluids. Long term infection with these viruses may even lead to liver cancer. There is a vaccine against hepatitis B but none against hepatitis C.
  3. Metabolic or other causes
    1. Non alcoholic fatty liver disease – occurs in individuals who do not consume, or drink little, alcohol. They develop fatty deposits over the liver. They occur commonly in people that are obese, diabetic, and have high blood cholesterol.
    2. Hemochromatosis – Liver is the storehouse for iron. Hemochromatosis can occur when there is too much iron deposited in the liver. This is usually a genetic condition. This may lead to cirrhosis and liver failure in some. This is one of the commonest inherited disorders in northern Europe affecting one in 300 people.
    3. Wilson’s disease – This condition results from too much deposit of copper in the liver. Normally the liver controls the amount of copper in the body. In Wilson’s disease this is disturbed. This is also an inherited condition that affects children and leads to liver cirrhosis and even failure.
    4. Autoimmune hepatitis - This occurs when the body’s immune system perceives the liver cells as foreign and attack it. This commonly affects women more than men.
    5. Primary biliary cirrhosis – this is also a condition that is thought to be of autoimmune pathology. There is severe cirrhosis that destroys the bile ducts that allow normal flow of bile thorough liver.
    6. Primary sclerosing cholangitis – There is severe inflammation of bile ducts that makes them scarred and narrow and prevents the flow of bile. This leads to pain, fever and jaundice and formation of bile stones.
    7. Obstetric cholestasis – This occurs during pregnancy. There is severe obstruction to bile flow that can pose a risk to the unborn baby. It affects 1 in 40 pregnancies in UK.
    8. Gall bladder stones – One in 10 people in UK may develop stones in their gall bladder. This is common among middle aged females who are overweight.
    9. Liver cancer – Liver cancer may be primary, where it begins in the liver, or secondary, where it begins elsewhere. Secondary liver cancer may be a metastatic or advanced form of another cancer like breast, lung, bone etc. that has travelled to affect the liver. Primary liver cancer risk rises in people with liver cirrhosis.
Edited by April Cashin-Garbutt, BA Hons (Cantab)

Liver disease symptoms

Liver is one of the most vital organs of the body. Liver disease may be short or long term.

Acute liver disease, or short term liver disease, manifests with severe symptoms that are recognizable.

However, long term liver damage, or chronic liver disease, often does not show symptoms unless much of the liver is damaged. It takes nearly two thirds of the liver to be damaged before there are symptoms of liver disease.

The liver also has a tremendous capacity to regenerate when damaged.

Classical symptoms of liver disease

Classical symptoms of liver disease are (1, 2, 3, 4) :–

  • Nausea, vomiting – these are often the first and most non descriptive symptoms of liver disease. They are often ignored until the disease progresses further.
  • Pain in the right upper part of the abdomen. This is where the liver is located so the pain and tenderness tends to concentrate in this region. Usually pain may result if there is enlargement of the liver. The pain is common in infective hepatitis. The pain may be severe in patients who have developed an abscess or boil over the liver due to infection. The pain is also excruciating in patients with bile duct obstruction called biliary colic. These patients need emergency care.
  • Hepatomegaly – Swelling or enlargement of the liver that can be felt over the abdomen. Usually this in an initial finding. In patients with a scarred or shrunken liver like in cirrhosis the liver may not be enlarged but may be felt on examination as a hard organ.
  • Jaundice leading to yellowish discoloration of the skin and whites of the eyes, nails and mucosal surfaces. This is caused by deposits of bilirubin or bile products that rise in the blood stream due to liver damage. Jaundice is one of the initial symptoms of liver disease and is commonly seen in infective hepatitis. It is also often the last to disappear.
  • Liver disease also commonly begins with symptoms of weakness, fatigue, weight loss and loss of appetite. These are again non descriptive symptoms that are often disregarded till further progress of the disease.

Variation in liver disease symptoms

Since there is a wide range of causes of liver diseases, the symptoms also vary in specificity in different conditions.

Those with gall stones for example may develop abdominal pain especially after a fatty or greasy meal and may also develop fever if there is an infection.

Those with infective hepatitis usually present with fever and jaundice.

Symptoms of liver cirrhosis

Patients who have developed long standing liver damage and cirrhosis also develop severe and serious symptoms. These symptoms are also seen in patients with liver cancer that may be primary or from secondary metastasis.

Symptoms of liver cirrhosis include –

  • Itching – this occurs due to deposits of bile salts under the skin
  • Easy bruising – since there is shortage of clotting factors there may be a tendency of bleeding easily and bruising on slight impacts. The blood vessels just under the skin are also friable and easily breakable and give an appearance of spider webs especially over the chest.
  • Imbalance of sex hormones leading to enlargement of breasts or gynecomastia in men. In some men this might also lead to impotence. This is usually seen over long term.
  • Brain affliction – Ammonia is a waste product of the body that is filtered by the liver. As the liver fails the blood levels of ammonia rises. This may affect the brain in a condition called hepatic encephalopathy. This may lead to confusion and disorientation and ultimately coma if left untreated.
  • Ascitis – accumulation of fluids in the abdomen. This leads to an enlarged and swollen belly.
  • Muscle loss and wasting – this occurs due to the inability of the liver to provide the body with adequate nutrients like protein.
  • Portal hypertension – this leads to increased pressure in the portal vein. This may lead to swollen veins and bleeding from the esophagus or rectum. The former manifests as blood-vomiting and the latter as bleeding via rectum in form of tarry black stools. (2)

Edited by April Cashin-Garbutt, BA Hons (Cantab)