is a
Gastroenterological disease, featuring
Inflammation of the
Liver . The clinical signs and prognosis, as well as the therapy, depend on the cause.
Hepatitis is characterised by fatigue,
Malaise , joint aches,
Abdominal Pain , vomiting 2-3 times per day for the first 5 days, loss of appetite, dark urine,
Fever ,
Hepatomegaly (enlarged liver) and
Jaundice (icterus). Some chronic forms of hepatitis show very few of these signs and only present when the longstanding inflammation has led to the replacement of liver cells by
Connective Tissue ; the result is
Cirrhosis . Certain
Liver Function Tests can also indicate hepatitis.
Most cases of acute hepatitis are due to
Viral infections:
- Hepatitis A
- Hepatitis B
- Hepatitis C
- D-agent (requires presence of the hepatitis B virus)
- Hepatitis E
- Hepatitis F (discredited)
- Hepatitis G
- In addition to the hepatitis viruses, some other viruses can cause hepatitis, including cytomegalovirus, Epstein-Barr virus, yellow fever, etc.
Please see the respective articles for more detailed information
:''See also Infectious Canine Hepatitis .
Hepatitis A is an Enterovirus transmitted by the Orofecal route, transmitted to humans through methods such as contaminated food. It causes an acute form of hepatitis and does not have a chronic stage. The patient's immune system makes Antibodies against hepatitis A that confer immunity against future infection. People with hepatitis A are usually advised to rest, stay hydrated and avoid alcohol. A vaccine is available that will prevent infection from hepatitis A for life. It can be spread through personal contact,consumption of raw sea food or drinking contaminated water.
Hepatitis B causes both acute and chronic hepatitis in some patients who are unable to eliminate the virus. Identified methods of transmission include Blood ( Blood Transfusion , now rare), Tattoo s (both amateur and professionally done), Horizontally (sexually or through contact with blood or bodily fluids), or Vertically (from mother to her unborn child). However, in about half of cases the source of infection cannot be determined. Blood contact can occur by sharing Syringe s in Intravenous Drug use, shaving accessories such as razor blades, or touching wounds on infected persons. Needle-exchange Programme s have been created in many countries as a form of prevention. In the United States , 95% of patients clear their infection and develop antibodies against hepatitis B virus. 5% of patients do not clear the infection and develop chronic infection; only these people are at risk of long term complications of hepatitis B.
Patients with chronic hepatitis B have antibodies against hepatitis B, but these antibodies are not enough to clear the infection that establishes itself in the and Lamivudine . In about 45% of persons on treatment achieve a sustained response.
Hepatitis C (originally "non-A non-B hepatitis") can be transmitted through contact with blood (including through sexual contact). It may lead to a chronic form of hepatitis, culminating in Cirrhosis . It can remain Asymptomatic for 10-20 years. No vaccine is available for hepatitis C. Patients with hepatitis C are prone to severe hepatitis if they contract either hepatitis A or B, so all hepatitis C patients should be immunized against hepatitis A and hepatitis B if they are not already immune. However, hepatitis C itself is a very lethal virus and can cause cirrhosis of the liver. The virus, if detected early on can be treated by a combination of interferon and the antiviral drug Ribavirin . There are variations in the response to this treatment regimen based on the genotype of the infecting virus.
Hepatitis D is an RNA Passenger Virus that cannot proliferate without the presence of Hepatitis B virus, because its Genome lacks certain essential Gene s.
Hepatitis E produces symptoms similar to Hepatitis A , although it can take a fulminant course in some patients, particularly Pregnant women; it is more prevalent in the Indian Subcontinent .
Another kind of hepatitis, Hepatitis G , has been identified.
Other viruses can cause infectious hepatitis:
Ethanol , mostly in Alcoholic Beverage s, is an important cause of hepatitis. Usually alcoholic hepatitis comes after a period of increased alcohol consumption. Alcoholic hepatitis is characterized by a variable constellation of symptoms, which may include feeling unwell, enlargement of the liver, development of fluid in the abdomen Ascites , and modest elevation of liver blood tests. Alcoholic hepatitis can vary from mild with only liver test elevation to severe liver inflammation with development of jaundice, prolonged Prothrombin Time , and liver failure. Severe cases are characterized by either obtundation (dulled consciousness) or the combination of elevated Bilirubin levels and prolonged prothrombin time; the mortality rate in both categories is 50% within 30 days of onset.
Roughly one in four people that consume more than three drinks per day during a period of ten to fifteen years will experience some level of alcoholic hepatitis.
Alcoholic hepatitis is distinct from cirrhosis caused by long term alcohol consumption. Alcoholic hepatitis can occur in patients with chronic alcoholic liver disease and alcoholic cirrhosis. Alcoholic hepatitis by itself does not lead to cirrhosis, but cirrhosis is more common in patients with long term alcohol consumption. Patients who drink alcohol to excess are also more often than others found to have hepatitis C. The combination of hepatitis C and alcohol consumption accelerates the development of cirrhosis in Western countries.
A large number of drugs can cause hepatitis. The Anti-diabetic Drug Troglitazone was withdrawn in 2000 for causing hepatitis. Other drugs associated with hepatitis {Link without Title} :
The clinical course of drug-induced hepatitis is quite variable, depending on the drug and the patient's tendency to react to the drug. For example, Halothane hepatitis can range from mild to fatal as can INH -induced hepatitis. Oral Contraceptive s can cause structural changes in the liver. Amiodarone hepatitis can be untreatable since the long Half Life of the drug (up to 60 days) means that there is no effective way to stop exposure to the drug. Statin s can cause elevations of liver function blood tests normally without indicating an underlying hepatitis. Lastly, human variability is such that any drug can be a cause of hepatitis.
Toxins and drugs can cause hepatitis:
Some metabolic disorders cause different forms of hepatitis. Hemochromatosis (due to Iron accumulation) and Wilson's Disease ( Copper accumulation) can cause liver inflammation and Necrosis .
''See below'' for Non-alcoholic Steatohepatitis (NASH), effectively a consequence of Metabolic Syndrome .
"Obstructive jaundice" is the term used to describe jaundice due to obstruction of the Bile Duct (by Gallstone s or external obstruction by Cancer ). If longstanding it leads to destruction and inflammation of liver tissue.
Anomalous presentation of Human Leukocyte Antigen (HLA) class II on the surface of Hepatocyte s—possibly due to Gene tic predisposition or acute liver infection—causes a cell-mediated Immune Response against the body's own liver, resulting in autoimmune hepatitis.
Autoimmune hepatitis has a prevalence of 1-2 per 1000. As with most other s are elevated, as is Bilirubin . Autoimmune Hepatitis can progress to cirrhosis. Treatment is with Steroid s and Disease-modifying Antirheumatic Drug s (DMARDs).
The diagnosis of autoimmune Hepatitis is best achieved with a combination of clinical and Laboratory findings. A number of specific antibodies found in the blood (antinuclear antibody (ANA), Smooth Muscle antibody (SMA), Liver/ Kidney microsomal antibody (LKM-1) and anti- Mitochondria l antibody (AMA)) are of use, as is finding an increased Immunoglobulin G level. However, the diagnosis of autoimmune hepatitis always requires a liver Biopsy . In complex cases a scoring system can be used to help determine if a patient has autoimmune hepatitis, which combines clinical and laboratory features of a given case.
Four subtypes are recognised, but the clinical utility of distinguishing subtypes is limited.
# Positive ANA and SMA, raised immunoglobulin G
# Positive LKM-1 (typically children and teenagers; disease can be severe)
# All antibodies negative, positive antibodies against soluble liver antigen (SLA)
# No autoantibodies detected
In severe cases of Alpha 1-antitrypsin Deficiency (A1AD), the accumulated Protein in the Endoplasmic Reticulum causes liver cell damage and inflammation.
Non-alcoholic Steatohepatitis (NASH) is a type of hepatitis which resembles alcoholic hepatitis on liver biopsy (fat droplets, inflammatory cells, but usually no Mallory's Hyalin ) but occurs in patients who have no known history of alcohol abuse. NASH is more common in women and the most common cause is Obesity or the Metabolic Syndrome . A related but less serious condition is called "fatty liver" (steatosis hepatis), which occurs in up to 80% of all clinically obese people. A liver biopsy for fatty liver shows fat droplets throughout the liver, but no signs of inflammation or Mallory's hyalin.
The diagnosis depends on history, physical exam, Blood Test s, Radiological imaging and sometimes a liver biopsy. The initial evaluation to identify the presence of fatty infiltration of the liver is radiologic imaging including Ultrasound , Computed Tomographic Imaging , or Magnetic Resonance Imaging . However, radiologic imaging cannot readily identify inflammation in the liver. Therefore, the differentiation between steatosis and NASH often requires a liver biopsy. It can also be difficult to distinguish NASH from alcoholic hepatitis when the patient has a history of alcohol consumption. Sometimes in such cases a trial of abstinence from alcohol along with follow -up blood tests and a repeat liver biopsy are required.
NASH is becoming recognized as the most important cause of liver disease second only to Hepatitis C in numbers of patients going on to Cirrhosis .
- Herrmann E, Sarrazin C. '' C-virus --virus kinetics and resistance mechanisms .'' Z Gastroenterol 1998;36:997-1008. PMID 15136939 in German
- Hadem J, Wedemeyer H, Manns MP. '' as a travel disease .'' Internist 2004;45:655-668. PMID 15118829 in German
- Emerson SU, Purcell RH. ''Running like water--the omnipresence of hepatitis E.'' N Engl J Med. 2004;351:2367-8. PMID 15575050
- Prof. Dr. med. Gert Frösner. ''Moderne Hepatitisdiagnostik'' ISBN 3-932091-50-7
