Hepatitis means infection or inflammation of the liver, most commonly caused by different viruses. These include Hepatitis A, B, C, D, and E; also Epstein-Barr virus (mononucleosis), cytomegalovirus, and others (see Hepatitis — the Different Viruses). The most common cause of hepatitis is alcoholic hepatitis, from a heavy binge (can be fatal). A variety of medicines can cause liver inflammation, as can toxins (poison mushrooms, etc.). Also, in terms of liver infection, note that bacteria are almost never responsible, so antibiotics won’t help (see Differences Among Germs).
The symptoms of hepatitis are the same, regardless of the cause. They may begin with simply feeling bad (like “coming down with something”), and a loss of appetite. Nausea and vomiting may occur. There may be some pain in the upper abdomen, especially on the right, but not necessarily. Eventually, there’s jaundice (eyes & skin turn yellow).
The first step in diagnosis is to prove that these symptoms are due to liver disease. That’s easily done, by a common blood test called “liver function tests” (LFTs) or “liver enzymes” (the ALT and AST). If these are high, there’s likely some sort of hepatitis; if they’re normal, so is the liver.
It’s important to realize that the level of ALT and AST don’t determine how sick you are. For Acute Hepatitis, the most important test is the Prothrombin Time, measured in terms of the “INR”). If that’s high (INR ≥1.6), the liver is failing to do what it needs to, and if it gets worse, could require transplant or lead to death. Most of the time with Acute Hepatitis, the INR is normal.
Once we identify some sort of hepatitis as the cause of symptoms, we do additional blood test to find out if it’s a specific virus like Hep A, B, etc. (Hepatitis Blood Tests). We also ask questions, like how much alcohol recently, any new medications, etc.
What happens depends on which virus is responsible. For example, Hep A almost always gets better on its own; Hep B & C also get better initially, but may become chronic (which can lead to Cirrhosis). Hep E (rare) has 25% mortality among pregnant women. There’s no treatment for acute hepatitis, other than avoiding alcohol and anything else toxic to the liver, and common sense measures like rest, try to eat whatever possible, drink enough fluids to stay well-hydrated. For the extremely rare case of liver failure from fulminant acute hepatitis of any cause, there’s always liver transplant.