Chronic Hepatitis B
Chronic hepatitis B is caused by infection with hepatitis B virus and represents a process of inflammation and necrosis of the liver, which an evolution of over six months.
Acute hepatitis with hepatitis B virus becomes chronic in about 5% to 10% of cases and represents a major virus reservoir. At global level it is estimated that over 2 billion people are infected with hepatitis B virus, only in Europe over 1 billion new cases are occurring annually. It is estimated that worldwide, there are currently over 350 million chronic carriers of hepatitis B virus. Most chronic carriers are in Asia and Africa, areas with high prevalence, more than 8% – 10%. Areas with low prevalence, less than 2%, are Australia, USA and Western Europe.
The natural reservoir of infection with hepatitis B virus is represented by infected people, the virus is localized in the blood, saliva and other body secretions (seminal fluid, vaginas secretions or breast milk).
The main source of infection is the infected blood. The disease also can be transmitted by sexually contact (through sperm or vaginal secretions) or can be transmitted from mother to fetus.
Virus transmission is done in various ways:
- Parenteral or percutaneous (through blood and blood derivatives, contact with infected medical instruments and also by tattoos);
- Non-sexual physical contact (within the family members or collectivity of children):
- Sexual contact.
- From mother to fetus.
The main serological markers of chronic hepatitis B are:
- HBs antigen, a marker of infectivity and appears both in the acute phase of disease, and in patients with persistent chronic hepatitis B. More than six months of this antigen after acute hepatitis, means that the disease is chronic. The disappearance of this antigen and the appearance of HBs antibodies, means that the patient is immunized, either by vaccination, either by infection.
- HBc antibodies, means that the disease has become chronic. These antibodies are also markers that show a replication of the virus in the body.
- HBe antigen, means that the virus is during the replication period. These antigens are positive in 25% of cases of chronic hepatitis B.
- HBe antibodies appear when the body is immunized against the virus and show that the virus is in a period of low replication. These antibodies if are positive in patients with chronic hepatitis B, means an improvement in prognosis of the disease.
- HBV DNA is the most sensitive marker of virus replication. Measurement of this marker permit the assessment of progression of chronic hepatitis B and patient response to treatment.
- HBs antibodies, means that chronic hepatitis B has healed or the patient is vaccinated.
Chronic Hepatitis B Symptoms
Symptoms of chronic hepatitis B are often nonspecific. In most chronic patients, the disease is discovered accidentally, when, during routine investigations is revealed elevated transaminases. Eventually a clinical examination occasionally may reveal hepatomegaly or splenomegaly. Most patients suffering from chronic hepatitis B are completely asymptomatic or may experience fatigue, drowsiness, decreased muscle strength. Episodes of jaundice occur rarely, usually in advanced stages of disease.
Chronic Hepatitis B Diagnosis
Laboratory tests can be more or less modified. Thus, there are types of chronic hepatitis B with minimum biological change, while others have obvious changes.
- Transaminases (AST, ALT) are elevated 2 or 3 times the normal value;
- Gammaglobulins are increased, there is a correlation between elevation of this parameters and disease activity;
- Serum albumin is decreased;
- Increased bilirubin is quite rare in chronic hepatitis B.
Virological markers are required, HBsAg as an expression of infection with hepatitis B virus, and markers of viral replication (HBV DNA, HBeAg).
Research of the existence of a superinfection with hepatitis D virus is necessary, because the two viruses are frequently associated.
Chronic Hepatitis B Treatment
General measures of a patient with chronic hepatitis B include a lifestyle which is closer to a healthy individual. Light physical activity will not be contraindicated. In mild to moderate form of disease, the patients can continue their professional activity. It will be absolutely contraindicate alcohol consumption, due to its liver toxicity. Diet is close to a healthy individuals and is strongly recommended a diet rich in protein, vegetables and fruits.
Antiviral medication is currently the treatment of chronic hepatitis B and is achieved with interferon and nucleoside analogues. These therapies are indicated in replicative forms of chronic hepatitis B, which are associated increased transaminases. Forms with normal transaminases respond poorly or do not respond to antiviral therapy.
It is recommended vaccination against hepatitis B, both in patients who are suffering from chronic hepatitis B and family members of the patients. It is also mandatory vaccination of all persons with risk for hepatitis B.
The primary aim of treatment is the suspension of hepatitis B virus replication or elimination of the virus from the organism and to reduce or stop the inflammation and necrosis of the liver. In the long run, is intended to prevent the relapse, stopping the progression to cirrhosis and liver cancer.