View source for 13. Chronic viral hepatitis (aetiology, types), pathomorphology and differential diagnostics, detection of virus associated antigens and their significance)

=== Introduction ===
Chronic hepatitis is defined by the presence of symptomatic, biochemical or serological evidence of continuing or relapsing hepatic disease for more than 3-6 months. Histological findings are also important to document a chronic hepatitis, by taking a biopsy from the liver.

=== Etiology ===
Hepatitis B, C and D (all consonants) can become chronic. Hepatitis by HCV becomes chronic in most cases (80%), while hepatitis by HBV or HDV becomes chronic in less than 10% of cases. Acute viral hepatitis progresses into chronic hepatitis if the body fails to clear the virus. Immunocompromised patients are at higher risk of developing chronic viral hepatitis.

=== Diagnosis ===
Chronic hepatitis B infection can be detected by serology. Elevated levels of HBsAg, HBeAg and <abbr>IgG</abbr> anti-HBc indicates chronic infection.

Chronic hepatitis C infection can be detected by the presence of anti-HCV antibodies and HCV RNA with the use of ELISA or PCR

Biopsy in chronic viral hepatitis can be used for grading and staging of the disease. While the histological picture of acute viral hepatitis shows mostly inflammation of the lobules chronic viral hepatitis show inflammation around the portal triads. In chronic hepatitis due to hepatitis B infection ''ground glass hepatocytes'' are characteristic. A type of necrosis called ''piecemeal necrosis'' is also characteristic.

=== Differential diagnosis ===
Chronic hepatitis can also be caused by:

* Hepatotoxic drugs (like methyl-DOPA)
* Metabolic disorders
** α1-antitrypsin deficiency
** Wilson disease
* Autoimmune chronic hepatitis
* Alcohol
* NAFLD

=== Clinical course ===
The symptoms of chronic hepatitis are highly variable and do not predict the outcome. Some patients only experience elevated levels of liver enzymes. Most patients however experience symptoms like fatigue, anorexia and bouts of mild jaundice. Patients may also develop hepatomegaly and spider angiomas.

Any chronic viral hepatitis can develop into cirrhosis, but chronic HBV and HCV infection increases the risk for hepatocellular carcinoma even without cirrhosis.

The clinical course of chronic viral heptitis is also highly variable. Patients may experience spontanous remission or may have the disease for the rest of their lives. Some patients develop cirrhosis rapidly while some never develop it. The major causes of death in chronic viral hepatitis are:

* Cirrhosis
** Liver failure
** Hepatic encephalopathy
** Bleeding from oesophageal varices
* Hepatocellular carcinoma

[[Category:Pathology 2 - Theoretical exam topics]]