Hepatitis B is one of the most dangerous infectious diseases that a modern person leading a socially active life risks encountering. Vaccines developed by doctors, with the help of which the disease is prevented, act for a limited period of time - they do not initiate the appearance of vaccine-induced hepatitis B, but only supply the corresponding antigen to the body. The service life of such a vaccine is from 5 to 7 years, after which a person must either undergo re-vaccination or increase the level of anti-HBs antibodies in another way. For this, modern doctors use an anti-HBs test.
Detailed description of the study
Hepatitis B is a disease caused by a DNA virus from the Hepadnaviridae family. The virus is widespread and is one of the most common causes of chronic liver diseases.
Hepatitis B infection occurs through contact with blood, and less often with other biological fluids. The virus enters the body when the integrity of the skin and mucous membranes is damaged during injections or medical manipulations with contaminated instruments. Health care workers who come into contact with blood are at increased risk of hepatitis B infection.
However, transmission of the hepatitis B virus through contact and household contact is possible in families where one of the people is a carrier of the infection. Infection is caused by the use of common hygiene items - razors, washcloths.
Sexual transmission is also one of the most common. In some countries, it leads among other epidemiological mechanisms. The hepatitis B virus is included by the World Health Organization in the list of sexually transmitted diseases. It is possible that a child may be infected with it during childbirth from an infected mother, as well as during breastfeeding. Cases of transmission of the virus through the placenta have been described.
Penetrating the body through the bloodstream, the virus enters the liver, where it attaches to the membrane of liver cells (hepatocytes). Its attachment to the surface of the hepatocyte is ensured by a protein called HBs antigen. The virus then penetrates the cell and multiplies within it. At the same time, the immune system produces antibodies aimed at attacking viral particles - antigens. This is how anti-HBs antibodies are formed.
Hepatitis B in most cases occurs in an acute form (90-95%) and ends with recovery. During the acute period, the virus multiplies in the liver, some people experience malaise, symptoms similar to a cold, sometimes accompanied by jaundice. As a result, persistent immunity to the infection is developed, which is assessed by the presence of anti-HBs antibodies.
Currently, vaccination against the hepatitis B virus is widely available. It allows you to form immunity against the pathogen for a period of up to 10 years. The immune response to vaccination against this virus is also assessed by the presence of a sufficient titer of anti-HBs antibodies.
What is a blood test for anti-HBs?
A blood test for the presence of anti-HBs antibodies is carried out both for healthy people in the period before and after vaccination, and for infected patients during the so-called “window” phase. During it, there is a mass extinction of surface antigens HBsAg, the presence of which is the main resulting factor indicating the presence of infection. The anti-HBs blood test was invented to monitor the level of antibodies, the presence of which indicates the body's fight against hepatitis. Monitoring anti-HBs levels is incredibly important for people who have survived acute hepatitis B - a steady increase in anti-HBs indicates a good prognosis for the course of the disease and possible recovery, while a decrease in the number of anti-HBs until antibodies cannot be detected indicates that that the body is seriously weakened and can no longer fight on its own. Moreover, some patients continue to circulate anti-HBs throughout their lives, so they have to regularly visit their doctor and have their blood tested for the presence of antibodies.
What do the analysis results say?
Based on the information obtained after deciphering the anti-HBs analysis, a picture of further treatment is built and predictions are made about the nature of the course of the disease. There are two main resulting factors – the level of anti-HBs antibodies and HBsAg. An increase in anti-HBs and a decrease in the amount of HBsAg indicates that the disease is gradually receding and the person is recovering. If anti-HBs and HBsAg are detected simultaneously in approximately equal quantities, an unfavorable prognosis of the disease occurs - this is a signal for the doctor, indicating the need to increase the intensity of treatment to avoid possible complications.
anti-HBc, antibodies
Anti-HBc – specific immunoglobulins to the nuclear antigen of the hepatitis B virus.
Synonyms Russian
Total antibodies to the HB-core antigen of the hepatitis B virus, Anti-HBcAg.
English synonyms
Anti-HBc IgM, IgG, Antibodies to Hepatitis B Core Antigen; HBcAb, Total, HBV Core Total Antibody (IgG + IgM), Core Antibody.
Research method
Chemiluminescent immunoassay.
What biomaterial can be used for research?
Venous blood.
How to properly prepare for research?
Do not smoke for 30 minutes before the test.
General information about the study
Viral hepatitis B (HBV) is an infectious liver disease caused by the DNA-containing hepatitis B virus. Among all the causes of acute hepatitis and chronic viral infection, the hepatitis B virus is considered one of the most common in the world. The actual number of people infected is unknown, since many people have an infection without significant symptoms and do not seek medical help. The virus is often detected during preventive laboratory tests. According to rough estimates, about 350 million people in the world are affected by the hepatitis B virus and 620 thousand die from its consequences every year.
The source of infection is a patient with HBV or a virus carrier. HBV is spread through blood and other body fluids. The virus is transmitted through unprotected sexual contact, the use of unsterile syringes, blood transfusions and organ transplants, as well as from mother to child during or after childbirth (through cracked nipples). The risk group includes medical workers who are likely to come into contact with the patient's blood, patients on hemodialysis, injection drug addicts, people with numerous unprotected sexual relationships, and children born to mothers with HBV.
The incubation period of the disease ranges from 4 weeks to 6 months. Viral hepatitis B can occur both in the form of mild forms, lasting several weeks, and in the form of a chronic infection with a long-term course. The main symptoms of hepatitis: jaundice of the skin, fever, nausea, fatigue, in laboratory tests - signs of liver dysfunction and specific antigens of the hepatitis B virus. An acute disease can occur quickly, be fatal, turn into a chronic infection or end with a complete recovery. It is believed that after suffering from HBV, stable immunity is formed. Chronic viral hepatitis B is associated with the development of cirrhosis and liver cancer.
There are several specific tests to detect current or past viral hepatitis B. To confirm the infection and clarify the period of the disease, an analysis for specific antigens and antibodies is used.
The hepatitis B virus has a complex structure. The main antigens that are important in laboratory practice are HBsAg (virus envelope antigen), HBcAg and HBeAg (antigens located in the virus core). HBcAg is highly immunogenic; antibodies to it are produced earlier than other immunoglobulins associated with the hepatitis B virus. The antigen itself is not detectable in the blood, since it is located inside hepatocytes - liver parenchyma cells, but the immune system of an infected person begins to produce anti-HBc even before clinical trials begin. manifestations, 3-5 weeks after the virus enters the body. With normal functioning of the immune system, this indicator can become positive at the end of the prodromal period of the disease. First, anti-HBc class IgM is produced, and from the 4-6th month of the disease, antibodies of the IgG class are produced. Anti-HBc IgM is synthesized in response to active viral replication and disappears during the recovery period, while anti-HBc IgG can circulate in the blood for years, sometimes for life. Total anti-HBc antibodies confirm the body's contact with the hepatitis B virus, even if other hepatitis markers are negative. When anti-HBc is detected, it is possible to clarify the stage of the disease and distinguish between acute, chronic or previous infection by determining individual classes of antibodies and antigens.
What is the research used for?
- To detect viral hepatitis B (even in the absence of other markers of hepatitis).
- For differential diagnosis of hepatitis.
- To detect previous viral hepatitis B.
- To determine the stage of the disease (taking into account the results of other indicators of viral hepatitis B activity).
When is the study scheduled?
- If viral hepatitis is suspected, there are clinical manifestations and there are no markers of other hepatitis (even with a negative test result for HBsAg).
- With data on previous hepatitis of unspecified etiology.
- During dynamic monitoring of a patient with hepatitis B (determination of the stage of the process with a joint study for other specific markers of infection).
What do the results mean?
Reference values
Result: negative.
S/CO ratio (signal/cutoff): 0 - 0.85.
Reasons for the positive result:
- acute viral hepatitis B (in the presence of anti-HBc, IgM and HBsAg);
- chronic viral hepatitis B (if additionally HBsAg is detected and there is no anti-HBc class IgM);
- previously suffered viral hepatitis B (in addition, it may be positive anti-HBs in the absence of other markers);
- maternal antibodies, determined in children under 18 months (with a previous history of viral hepatitis B in the child’s mother).
Reasons for negative results:
- absence of hepatitis B virus in the body;
- incubation period of a viral infection (before the onset of antibody production).
What can influence the result?
In 1% of patients after transfusion of blood or plasma components, there is a possibility of a false-positive result (with a previous history of viral hepatitis B in the donor).
Important Notes
- A separate study of total antibodies to viral hepatitis B does not accurately determine whether the patient is infected. The examination should be comprehensive - taking into account the clinical picture of the disease, data from biochemical studies and other specific markers of hepatitis.
- There are recommendations for prescribing this test to patients who are planning immunosuppressive therapy, since there is a high risk of reactivation of a latent infection or chronic viral hepatitis B with a fatal outcome.
Also recommended
- HBsAg
- https://www.helix.ru/kb/item/07-004
- HBeAg
- anti-HBe, antibodies
- anti-HBs, antibodies
- HBV, DNA [real-time PCR]
- HBV, DNA quantitative [real-time PCR]
- anti-HDV, antibodies
- Anti-HCV, antibodies, ELISA
- Gamma-glutamyl transpeptidase (gamma-GT)
- Alanine aminotransferase (ALT)
- Aspartate aminotransferase (AST)
- Total alkaline phosphatase
- Serum albumin
- Total bilirubin
- Total cholesterol
- Thrombin time
- Fibrinogen
Who orders the study?
Infectious disease specialist, hepatologist, gastroenterologist, therapist, general practitioner, surgeon, hematologist.
Literature
- Harrison's Principles of Internal Medicine. 16th ed. NY: McGraw-Hill; 2005: 1822-1855.
- Vozianova Zh.I. Infectious and parasitic diseases: In 3 volumes - K.: Health, 2000 - T.1.: 601-636.
Why else is it necessary to monitor the level of anti-HBs and HBsAg?
Unfortunately, complications caused by the acute form of hepatitis B can persist even after the disease disappears and haunt a person for the rest of his life. Hepatitis B is a disease that is systemic in nature. This means that a person suffering from hepatitis is exposed to a complex attack on various organs and systems of the body. In this case, regular testing is necessary - a search for anti-HBs will provide accurate information about the status of the disease. In addition, monitoring HBsAg is also important - in a healthy person, the presence of this surface antigen indicates the possible occurrence of liver carcinoma or cirrhosis.
Blood testing for anti-HBs is critical in modern medicine. Due to the nature of vaccination, the fight against hepatitis B - especially its acute form - is quite unsystematic and largely relies on chance. Timely analysis allows not only to predict the course of the disease, but also to prevent its development in the early stages, saving a person from the severe phase of acute hepatitis B. Moreover, the cost of the analysis is quite affordable, which is a decisive factor for people at risk. They can afford regular screening and prevention that protect the patient’s life and health from hepatitis B.
