The main danger of hepatitis is that it is difficult to detect. A reliable method for determining hepatitis in humans is the presence of viral hepatitis markers in the patient’s blood. Thanks to their presence, the doctor can determine the type of hepatitis and the stage of the course of the disease, prescribe the appropriate treatment. From the article you will learn all about the types of hepatitis, serological markers of viral hepatitis, the features of the interpretation of test results.
Hepatitis - a dangerous viral disease
Viral hepatitis is an inflammatory process in the liver caused by one of the 6 types of hepatitis (A, B, C, D, E and G). Infection with viruses occurs in different ways: hepatitis A and E - through water, household appliances and contaminated food, hepatitis B and C - through blood and other biological fluids. But hepatitis D is considered an additional infection that can occur in a person with another form of hepatitis.
Non-specific harbingers of infection are: anorexia, nausea, fever and pain in the right hypochondrium. Yellowness of the integument appears after the extinction of these symptoms. Acute hepatitis often becomes chronic, and with their progression, liver failure occurs. According to estimates by the World Health Organization, 1.4 million people die every year from various forms of this viral infection in the world.
Characterization of hepatitis
Hepatitis A causes a single-stranded RNA virus. This is the most common form of hepatitis in children and adolescents, which can be asymptomatic. It is transmitted enteral (fecal-oral). It does not go into a chronic form. Vaccination and previous illness form a strong immunity to this type of virus.
Hepatitis B provokes a DNA-containing virus. The most dangerous form that can be fatal. Vaccination provides immunity to the virus. It is transmitted parenterally (blood and body fluids). The risk of perinatal transmission of the virus to the fetus from an infected mother is very high.
Hepatitis C causes an RNA-containing virus that is transmitted parenterally. It becomes chronic in 75% of cases. There is no vaccine. There are several serotypes of this virus, the distribution of which varies geographically. Sexual or vertical (from mother to fetus) infection is very rare. It can be asymptomatic even in the acute phase, goes into a chronic form with relapses that can last for decades.
Hepatitis D causes an RNA-containing defective virus (delta agent) that is able to replicate only in the presence of hepatitis B. It is transmitted parenterally through blood and body fluids.
The causative agent of hepatitis E is an RNA-containing virus. Transmission is via the enteral route. There are 4 serotypes that are especially dangerous for pregnant women in the second half of pregnancy. It can lead not only to the death of the fetus, but also to the death of the mother.
Hepatitis G causes an RNA-containing virus, which often combines with other types of hepatitis. In an independent form, it is asymptomatic. Infection occurs parenterally. Sexual transmission is possible, vertical transmission of the virus from mother to fetus is likely.
Alcoholic hepatitis is also distinguished, which is associated with the intake of alcohol-containing drinks.
A special form of hepatitis is autoimmune. The etiology of it is not clear. During the period of the disease, antibodies are released into the bloodstream that attack healthy hepatocytes. In 25% of cases, it is asymptomatic and is diagnosed only when it has already provoked cirrhosis of the liver.
Features of infection
In 40% of cases of hepatitis, the source of infection remains unclear. With enteric transmission of the virus, you can get hepatitis in public transport, from banknotes and other public items.
Possible infection with unprotected sexual contact. People at this risk group are advised to take hepatitis tests every 3 months.
About 2% of donated blood may contain hepatitis viruses.
Piercing, tattooing, manicure and pedicure can also cause infection if the sanitary standards for sterilization of instruments are not observed.
The vertical route of transmission of the infection from the infected mother to the fetus is rare. Only acute hepatitis in the third trimester of pregnancy is considered very dangerous to the fetus. Infection of the baby during childbirth is unlikely.
Acute course of the disease
Most often, hepatitis occurs in acute form. During the disease, the following periods are distinguished:
- Incubation. The virus spreads in the body but does not cause symptoms.
- Prodromal (preicteric). Non-specific symptoms appear: nausea, vomiting, fever, pain in the right hypochondrium.
- Icteric. On the 10th day of the course of the disease, urine becomes dark, and the skin and mucous membranes become yellow. The liver is enlarged, painful on palpation.
- Restorative. At 4-8 weeks after infection, yellowness disappears, and hepatitis resolves spontaneously.
WHO activities
Statistics is relentless - 0.5 billion people in the world have a chronic form of hepatitis B and C. About 57% of liver cirrhosis and 8% of primary liver oncology are caused by chronic hepatitis.
Hepatitis C infection can be prevented by ensuring the safety of water and food (hepatitis A and E), vaccination (hepatitis A, B, E), donor screening, infection control and sterility of injection equipment (hepatitis B and C).
In 2011, the Global Hepatitis Program was approved by the World Health Organization, and World Disease Day was established on July 28. Since 2014, this program has been included in the cluster on tuberculosis, HIV-AIDS, malaria and other tropical diseases.
Why take tests?
Preventive tests for hepatitis are of great importance in connection with the asymptomatic onset of the disease. For diagnosis, one or more markers are used, which determine not only the presence of infection, but also the stage of the course of the disease.
It is necessary to take into account the general epidemiological situation in the region of the place of residence. Especially for those types of hepatitis that can be transmitted through water and through the home.
Treatment in the early stages of the disease gives a positive trend and a complete cure.
What is a marker?
Marker refers to specific substances in the blood that are produced in response to an attack of pathogens. Markers of viral hepatitis can be:
- Antibodies that are produced by white blood cells on viral particles.
- Actually viral antigen proteins.
- Specific markers of viral hepatitis, the analysis of which is carried out during blood sampling.
- Fragments of nucleic acids (DNA and RNA) of the hepatitis virus itself.
In clinical studies of a patient’s blood, the following viral hepatitis markers are determined: A, B, C, D, E, and G.
How it's done?
Blood sampling for markers of viral hepatitis is a simple procedure. Blood is taken from the cubital vein. It is advisable to take an analysis in the morning and on an empty stomach. In pregnant women, blood sampling for this analysis is possible at any time. In addition, at any time, blood is taken on markers of viral hepatitis upon admission to the hospital and in preparation for surgical operations.
It is advisable to do the analysis for people who are at risk - injecting drug addicts, with promiscuous sexual intercourse (promiscuity) and unprotected sex. Blood sampling for markers of viral hepatitis and its standard algorithm of conduct.
Viral hepatitis A
This type of hepatitis is the most common, proceeds mainly without complications, sometimes passing spontaneously or with minimal treatment.
A blood test for markers of viral hepatitis A is prescribed in the following cases:
- With the appearance of clinical manifestations of hepatitis.
- With the appearance of yellowness of the integument and mucous membranes.
- With an increase in the protein-enzyme aspartate aminotransferase (AcAt), which is produced in the liver, in the blood.
- In contact with an established patient.
- If there are foci of infection, analysis for hepatitis markers is carried out in all contact persons.
- When establishing immunity to viral hepatitis A during vaccination.
Interpretation of examination data for markers of viral hepatitis A:
- A negative result indicates a lack of immunity to the virus in the patient.
- Positive result: antibodies of immunoglobulins M (IgM) to this type of hepatitis were detected - the acute phase of the disease is on; detection of IgG antibodies to this type of hepatitis indicates that the body has already met with this viral infection and has immunity to it; detection of hepatitis A antigens and RNA virus - the presence of a virus in the body.
Hepatitis B
This type of hepatitis is the most significant public health problem worldwide. Hepatitis B virus - DNA-containing, leads to an acute and chronic course of the disease with damage to liver cells, up to a fatal outcome.
A study on markers of viral hepatitis B is prescribed:
- In preparation for vaccination and in confirming its effectiveness.
- When detecting antigens of viral hepatitis B in the blood and with the clinical manifestations of the disease.
- With an increase in blood levels of AsAt protein.
- In the presence of chronic liver pathologies, bile ducts.
- With focal infections.
- In preparation for parenteral manipulation, hospitalization.
- When planning pregnancy and if it is available.
- When examining blood donors.
- When belonging to a risk group (unprotected sex, promiscuity, injecting drugs).
The absence of markers in the blood indicates that the patient has not been immune to this virus.
The detection of the following viral hepatitis B markers is interpreted as follows:
- Antigens in the blood (HBsAg) - the presence of an acute or chronic form of the disease, virus carrier.
- IgM antibodies - previous infection or vaccination effects.
- IgG antibodies are a previous disease.
- HBeAg and Pre-S1 - high infectivity, active virus replication, risk of perinatal transmission.
- Pre-S2 - the presence of one of the forms of hepatitis B.
- Antibodies Pre-S2 - recovery from illness.
- DNA polymerase and virus DNA - the presence of hepatitis B and active replication of the virus.
Hepatitis C
A feature of this form of hepatitis is the frequent course without jaundice and in a mild form. In the absence of diagnosis in the early stages, it becomes chronic with the appearance of cirrhosis and malignant tumors in the liver.
A blood test for markers of viral hepatitis C is carried out:
- With increasing levels of AlAc.
- In preparation for operations and parenteral manipulations.
- When planning a pregnancy.
- With clinical manifestations of hepatitis.
- When belonging to a risk group (unprotected sex, promiscuity, injecting drugs).
The absence of hepatitis C markers in the patient’s blood indicates the absence of infection or the incubation period (4-6 weeks). Markers are absent in the seronegative variant of hepatitis C.
Deciphering the markers of viral hepatitis C:
- Hepatitis C IgM antibodies are the active phase of virus replication.
- IgG antibodies to this type of hepatitis - the presence of the virus is possible, or there has already been a meeting with the virus.
- Antigens of the virus or its RNA - the presence of viral hepatitis C.
Viral hepatitis D
The RNA-containing virus of this form of hepatitis is adjacent to hepatitis B, significantly complicating its course. Examination for markers of viral hepatitis D is carried out in the diagnosis of this disease and in the diagnosis after treatment.
The absence of markers means that the virus is not detected in the blood.
Positive markers:
- IgM antibodies to this form of hepatitis are an acute stage of the disease with active replication of the virus.
- IgG antibodies to hepatitis D virus - a meeting with the virus has occurred in the past.
- Antigens of the hepatitis D virus or its RNA - the presence of infection.
Hepatitis E
The symptom and clinical picture is similar to hepatitis A. It is especially dangerous during pregnancy - it causes gestosis of the last trimester with a triad of symptoms: edema (external and internal), proteinuria (protein in the urine), hypertension (high blood pressure). In severe forms of the course, a fatal outcome is possible for both the fetus and the mother.
In addition, the analysis is prescribed:
- With severe symptoms of hepatitis.
- To persons who received blood transfusions or did hemodialysis.
- Injecting drug addicts.
- Persons from endemic areas.
- When evaluating the effectiveness of vaccination.
The absence of markers indicates a lack of immunity to this type of hepatitis.
The presence of antibodies - immunoglobulins IgM to hepatitis E indicates an acute stage of the disease, IgG antibodies - immunity is due to a previous meeting with the hepatitis E virus, antigens or RNA of the virus indicate the presence of infection.
Type H hepatitis
This type of hepatitis in symptoms and clinical presentation is similar to hepatitis C, often proceeds with it and hepatitis B and D.
Indications for the analysis are the diagnosis and monitoring of the disease.
A negative result indicates the absence of immunity, and the detection of antigens indicates a previous meeting and the presence of immunity. Detection of an RNA virus in the blood indicates the presence of the virus and its active replication.