hepatites

Hepatitis is inflammation of the liver. It can be acute or chronic and arises from infections, alcohol or drug toxicity, autoimmune disease, or metabolic conditions. Viral hepatitis, caused by five distinct viruses (A, B, C, D, and E), is the most common form of infectious liver inflammation worldwide and is a major public health concern.

Hepatitis A is fecal-oral, usually self-limited, and preventable by vaccine. Hepatitis B is bloodborne and can be acute or chronic; transmission includes blood, sexual contact, and mother-to-child. Vaccination prevents HBV. Hepatitis C is spread mainly by blood and often becomes chronic; antiviral therapy can cure most cases, but no vaccine exists. Hepatitis D occurs only with HBV infection and worsens disease; HBV vaccination protects against HDV. Hepatitis E is typically fecal-oral and usually self-limited, with higher risk in pregnancy; vaccines exist in some countries.

Symptoms range from none to fatigue, loss of appetite, abdominal discomfort, jaundice, dark urine, and pale stools. Some infections present only with mild symptoms; others can progress to liver failure, cirrhosis, or liver cancer over time, especially with chronic hepatitis.

Diagnosis combines liver function tests (ALT and AST), bilirubin level, and serological testing for viral markers, sometimes followed by molecular tests to detect viral RNA or DNA. Imaging and, rarely, liver biopsy help assess liver damage and guide management.

Treatment depends on the cause. Acute viral hepatitis A and E generally require supportive care; chronic hepatitis B and C are treated with antiviral medications that can control or eradicate infection. Prevention focuses on vaccination for hepatitis A and B, safe injection and sexual practices, safe food and water, and harm-reduction measures for people who inject drugs.