Hepatitis is inflammation of the liver. It can be caused by infection or by poisoning (for example, with alcohol, some industrial chemicals and some drugs).
When the liver becomes inflamed, its cells can’t work properly to turn food into chemicals that our bodies can use, or to turn waste products into chemicals’ that are easy to get rid of in urine or faeces. The inflamed liver tissue also swells, partly blocking the free flow of blood and other fluids, including bile, through the liver.
Hepatitis ranges from mild to very severe. Mild hepatitis may not cause any noticeable symptoms, just an off-colour feeling for a few days. Severe hepatitis causes a very serious disturbance of health, and can occasionally be fatal.
Jaundice (in which most of the tissues and fluids in the body turn yellow to dark orange) is the most obvious sign that the liver isn’t working properly. Jaundice is most noticeable in the skin, whites of the eyes and lining membranes. In acute hepatitis the urine is also dark orange or red while the stools (faeces) are pale.
Jaundice means that the liver can’t properly break down pigments from worn-out red blood cells, so that they build up in the blood and tissues. If the liver is inflamed enough to cause jaundice, many of its other important functions will also be disturbed.
You can become jaundiced from causes other than hepatitis. These include blocking of the duct that drains the gall bladder into the bowel (obstructive jaundice), and when anything causes red blood cells to wear out or break up too quickly (haemolytic jaundice) so that the liver can’t process the blood pigment fast enough to stop it from building up in the blood. You can also get orange staining of the skin from eating too many carrots, but this isn’t jaundice.
The rest of this section is about infectious hepatitis.
The symptoms of acute viral hepatitis are jaundice, dark urine, pale stools, loss of appetite and energy, biliousness, fever, headache, aching muscles and generally feeling unwell. Sometimes there is also pain in the right upper abdomen and back. Symptoms range from none to very severe and may come on acutely or more slowly.
Most hepatitis is caused by viruses. The main ones are the hepatitis viruses of which we know six types: А, В, C, D (delta), E, and G.