When there is reason to believe that a person has contracted hepatitis, you can take a surface antigen test and determine the likelihood of signs of jaundice in advance, before these processes in the body are launched in full force.
Today, according to statistics, about 2 billion people around the world are already infected. And nearly 350 million suffer from chronic hepatitis. In connection with this situation, doctors strongly recommend that all pregnant women be tested for hepatitis B 2 times: when she becomes registered at the antenatal clinic, and during the prenatal period.
This article will present the norms of the hbsag viral marker for hepatitis B, as well as information on why it is necessary to determine antigens in the blood and what is the role of their satellite antibodies. An antigen is a protein that forms an antibody that can find a virus by its genome, capture and destroy it. This is how our immune system works. The purpose of laboratory analysis is to detect viral antibodies in the blood in time, to determine the stagediseases, type of virus and prescribe appropriate supportive therapy. A person, having received an analysis in his hands, should consult a doctor about the results. For example, the surface antigen of the hepatitis B virus is negative - what does this mean? And what are the reference values of the indicators given in the tests? All this should be studied.
What is hepatitis B surface antigen?
The most active defenders that help the body cope with the "enemy" are our own antibodies in the blood. They are partially transmitted to a person from the mother, and then they are produced in response to stimuli - antigens, and will remain for life.
An antigen is a foreign substance that harms the body. These are foreign proteins of microbial or non-microbial origin that cause the body's immune response. In general, "antigen" is translated from English as antibody generator - a manufacturer of antibodies. This article is about the antigens and antibodies of the hepatitis BV virus, therefore, information will be provided on those proteins that are parts of the hepatitis B virus.
Antigens to proteins are internal (nuclear) and surface. We'll talk about them later.
The antigen-antibody system exists all the time that a person walks this earth. Nature has endowed us with smart and powerful protection against viruses and bacteria, and in principle, with strong immunity, the body is able to cope with the threat itself.
But at present, human immunity is quite weak compared to the level of immune protectionprevious generations, and we can no longer imagine a normal life without medication.
Currently, hepatitis B is well treated. It is only necessary to start therapy at the beginning of the disease, when the viruses have not yet damaged the liver too much. What to do if hepatitis B surface antigen is detected? The norm for an antigen is its absence. Since the presence of hbsag indicates infection.
How is the antigen detected?
When and by whom was the hepatitis B surface antigen discovered? It was discovered by the American medical researcher Baruch Blumberg. He made a breakthrough in understanding the mechanisms of origin of some infections.
A few years later, during subsequent studies, Blumberg came to the conclusion that antibodies in humans are produced against a specific protein, namely the one contained in the shell of the virus. Later, HBsAg, the surface antigen of the hepatitis B virus, was found in human blood without the virus. The antigen was purified and used to create a vaccine against the virus. Baruch Blumberg won the Nobel Prize in Medicine and Physiology in 1963.
Subsequently, the found antigen began to be used as a serological marker of the disease. In medicine, it is now known as the surface antigen of the hepatitis B virus - the Australian antigen.
HBV surface and core antigens
The hepatitis virion consists of a shell and personal DNA. The protein that is outside and makes up the capsid is called surface, and the one that is inside the capsid is called internal. nuclear proteins-there are two antigens - HBcAg, HBeAg.
The surface antigen of the hepatitis B virus - the hbsag protein - is able to activate oncological processes in the liver and, in addition, spreads throughout the body.
Features of the HBV virus
The hepatitis virus has such a strong defense that it is not easy to kill it. Even if you try. In a solution of ethyl alcohol (80%), the virus still lives for 2 minutes. Therefore, the instruments in hospitals before the operation are not just wiped with alcohol, they are disinfected for a long time in special chambers, using special methods. The virion is not destroyed by repeated freezing and thawing; it cannot be destroyed with weak solutions of disinfectants, for example, formalin solution (0.1%) is not afraid of the virus.
Hepatitis B virus lives 7 days outside the carrier's body. During this time, a lot of people will have time to become infected. Moreover, getting to a new carrier, it becomes active and multiplies again.
When a virus enters the body, it immediately attacks the liver in a targeted manner. It penetrates the nucleus of the hepatocyte and causes the cell to produce new viruses. The virus cannot reproduce without a host, and its entire "life" is a parasitic symbiosis. Due to the fact that viruses are inside the body's own cells, it is impossible to apply antibiotics to them.
Negative and positive antigen. What does this mean?
The antigen appears in the blood approximately 14 days before the end of the incubation period. During the analysis, it can already be identified, albeit in a small way.quantity, but it is present. The incubation period for HBV hepatitis lasts from 4 to 12 weeks. Disappears from the bloodstream after the appearance of antibodies - HBs. That is, after 3 months with successful therapy, but sometimes recovery occurs much later.
If, after passing the test, a person receives a result that says that the antigen of the hepatitis B virus is positive, this is a reason to think. This means that there is a virus in the blood and protective mechanisms are active. Even if the person does not yet feel unwell. It may be necessary to retake this analysis again.
Another result that occurs in the medical record is that the hepatitis B surface antigen is negative. This result means that everything is in order and no HBV proteins were found in the taken blood.
Note that the result is not always accurate. It can be both false positive and false negative. Why? There may be several reasons for this:
- in the blood antigens to hepatitis C, D, E, but not B;
- hepatitis virus mutated;
- a person has contracted a malignant type of virus;
- a person is a carrier of a "sleeping" virus;
- mixed hepatitis B+D;
- superinfection, when the dormant B virus was already present in the body, and the person also became infected with the D virus.
If the surface antigen of the hepatitis B virus is doubtful, what is the preparation for and what to do with such a result? It is necessary to pass additional serological tests, find out if there are changes in the size of the liver, and take tests for antibodies. Then the doctor canto tell more, having the results of certain studies in hand.
The worst thing is if the virus has mutated. Then the antibodies to the surface antigen of the hepatitis B virus, which were developed due to vaccination, will not work. However, that's not all.
Antibodies to hepatitis B surface antigen
In addition to detecting HBsAg and HBcAg in tests, HBsLg, HBcLgG and HbcLgM antibodies can also be found in blood samples. What follows from these data? Antibodies circulating in the body indicate that inflammation is still present, or the person has had an acute infection in the past, or the patient is chronically ill. The complete absence of antibodies is a sign of the absence of inflammation and any protection.
In general, antibodies to the hepatitis B surface antigen appear several months after the detection of HBsAg or HBcAg. The norm of antibodies in the blood against the surface antigen is about 100 mU / ml. This indicator needs to be monitored from time to time. If the indicator falls below one hundred units, you need to be vaccinated.
The appearance of antibodies in the blood instead of HBcAg, the surface antigen of the hepatitis B virus, is called seroconversion. This turning point signifies the approach of recovery. And the period of time between the appearance of antigens and a significant decrease in the surface antigen of the hepatitis B virus is called the "serological window". Usually this "window" stretches for 3-6 months. But if the time interval is longer, then there is nothing to worry about. Even chronic hepatitis can be cured if detected early.
Quantitative surfaceantigen. Norms
What are the norms for hepatitis B surface antigen? Standards are provided for each marker in order to adequately evaluate the resulting figures through comparison, and so that physicians around the world can start from standard units of measurement.
So, what should be the surface antigen of the hepatitis B virus? The norm of the indicator is 10 mU / ml. However, you need to know other nuances. If the results of the hepatitis B surface antigen test (quantitative test) are less than the reference value, this means that the result is negative. That is, hepatitis B is not detected. And when the antigens in the blood are more than the specified mark, then the analysis is considered positive.
Numbers from 10 to 100 in the analysis occur in such cases:
- Acute HBV is recovering.
- The vaccination was successful.
- The disease is chronic but with low infectivity.
It happens that the test result in screening studies is questionable. Then a special verification analysis is done, where the method of competitive ELISA is used. During the test, the hepatitis B surface antigen is neutralized with specific antibodies. The result of such a study is many times more accurate.
Positive tests must be rechecked. When the test is retaken, it must be taken under the same conditions and at the same time as the first time.
Mutant forms of hepatitis and antigen
Like all compounds in the biological world, viruses are subject tonatural structural changes, that is, they mutate. Since antigens react only to one type of protein, they are helpless before the mutated capsid. And modern tests cannot detect a mutated virus. It takes years of research to find the formula for each virus and compile a test for it. And those studies that are now have not yet given satisfactory results.
Who needs to be tested without fail?
Since the surface antigen of the hepatitis B virus is very dangerous, this protein is a real poison for the liver, disrupts its functions and does not give any symptoms, it is advisable for everyone to be tested every couple of years. There are certain groups of people who simply need to regularly donate blood for research:
- Those who work in a medical institution or in a public catering.
- To tourists visiting Africa.
- After contact with a case of hepatitis.
- Asocial individuals.
- To those in prison.
- After hemodialysis.
- To become a blood donor.
Other citizens are tested for surface antigen at their own discretion. Literally everyone has risks of getting infected, especially young people who like to get tattoos on their bodies. If the tattoo artist does not disinfect the instruments, the risk of infection is incredibly high. The same applies to low-skilled dental offices and nail salons.
HBsAg rapid test
Determination of the surface antigen of the hepatitis B virus is possible not only inlaboratory conditions, but also at home, if there is a special immunochromatographic rapid test. This is a one-time test that determines the presence or absence of an antigen using one drop of blood from a fingertip.
The role of macrophages in the destruction of the virus
Hepatitis B is cleared from the body by large immune cells called macrophages. The HBV virus immediately tries to get inside the hepatocyte cell - the liver cell, and change its structure. If the immune system is strong, then its cells begin to kill both the damaged hepatocyte itself and those he althy cells that are nearby. Scar tissue grows in place of he althy cells. HBsAg immune complexes determine extrahepatic tissue damage by the virus, that is, they "catch" the virus that has left the liver area and spread further with the blood.
How is the liver cleared of the virus? This happens only due to the death of liver cells and their removal from the body. Antibodies and antigens are phagocytosed, that is, captured by macrophages, and excreted through the kidneys. However, with certain pathologies, this process is disrupted. Immune complex pathologies lead to diseases such as arteritis, glomerulonephritis and others.
The strong immune response of the body causes severe inflammation in the liver. Acute hepatitis can be very serious and require treatment in an infectious disease ward.
Antibody blood sampling procedure
Blood for hepatitis B surface antigen is taken from the left hand. Be sure to fast for at least 6 hours. At the same time for 5days before the analysis, you should not drink alcohol and eat fatty foods. It is not recommended to be nervous before the test, to quarrel with someone the day before. No smoking. Otherwise, the result will be incorrect. Ideally, 10 minutes before donating blood, just sit on a bench in the waiting room.
What does a he alth worker do? The arm above the elbow should be tied with a tourniquet. The needle is inserted gently into the vein in the elbow area, and the blood through the needle enters special medical hoses. Then the specialist takes the required amount of blood into a test tube.
Recommended vaccination dates for adults
If a small amount of antibodies to the surface antigen of the hepatitis B virus is detected in the blood, the doctor will insist on vaccination. This is the only way to 100% protect against liver damage today.
He alth workers need a vaccine every 5-7 years. It is enough for other categories of the population to be vaccinated every 15 years. But there are special cases when it is forbidden to do this:
- Vaccinations are prohibited for those who have recently been ill with one of the strains of the hepatitis virus.
- People who are allergic or intolerant to vaccine components.
- People over 50-55 years old.
- During the period of weakness of the body due to acute respiratory infections.
Before making a decision about vaccination, it is advisable to consult with your doctor. After the injection, a person may feel pain in the stomach, general weakness, body temperature often rises. If at the injection site there isredness for a few days is also a normal reaction to the vaccine.
Other virus markers
Determination of the surface antigen of the hepatitis B virus - this is only a small part of all the tests to be taken. This analysis provides little information.
HBsAg serological marker is the main and cheapest way to know the diagnosis in advance. But there are other markers of the virus that appear and disappear at strictly defined periods:
- HBeAg is in the blood from 1 week after the appearance of HBsAg, decreases after 20-40 days. This is the nuclear "e" antigen. Nuclear means internal. It indicates a high infectivity of the blood. The risk of perinatal (at birth) transmission of the virus is very high. The marker also indicates the active reproduction of the virus in the body.
- HBcAg - nuclear core antigen of HBV. Its presence means that a person is either sick now or has had an acute infection and is a carrier of antibodies to HBV. Detected exclusively during morphological studies.
- LgM anti-HBc antibodies (class LgM) to the core antigen. Antibodies stay in the blood for 60-540 days.
- Anti-HBe - protective antibodies to the "e" antigen, show hepatitis in exactly 90% of cases after 60 days from infection.
- Anti-HBc (total) - immunoglobulins to hepatitis B core antigen. Present in the body 7-14 days after HBsAg. This is a very important diagnostic indicator. Gives a clearer picture of what is happening if HBsAg is negative. May indicate post-vaccination antibodies or a previous inflammatory process inliver.
Markers such as LgG and nuclear antibodies remain in a person's blood for life, others disappear as hepatitis develops in the body.
What can all these markers tell doctors? After examining all the indicators, the specialist makes his verdict. The results might look like this:
- Chronic active hepatitis B.
- Acute hepatitis (mutant, wild or common).
- Just being a carrier.
- Latent chronic infection.
- Resolved acute hepatitis.
- Normal immune response after a vaccine.
But don't think that one marker will give all the answers. The diagnosis is made after considering many tests, the general functional state of the liver and the patient's complaints. If a person turns out to be just a carrier of the virus, he does not need to be treated. In its inactive form, it does not harm the body.
Diagnosis of the condition of the liver
The purpose of additional diagnostics is to determine the degree of liver dysfunction. The color of the sclera of the eyes and urine determines only that the level of bilirubin has become above normal. Other liver dysfunctions cannot be visually traced.
What tests should be done after confirmatory analysis? At least 5 more examinations and procedures are needed:
- The doctor must know the concentration of bile acids in the patient. The gallbladder and its ducts are examined. This is how the condition of a patient with hepatitis is controlled.
- Control of the clotting system. The production level must be setprothrombin, which is involved in the process of blood clotting after injury to the body.
- Studies of such function of the liver as its participation in protein metabolism. The parenchymal organ is involved in the production of such proteins: globulin, fibrogen and albumin.
- Alkaline phosphatase study. The analysis is needed to detect metastatic tumors in the long course of moderate and severe chronic hepatitis.
- Study of the excretory function of the liver. That is, to what extent the body has retained the ability to cleanse the blood of toxins. This is important for determining the chronic stage of hepatitis B.
- And the level of cholinestasis is also checked.
Here are the diagnostic tools used for liver tests:
- Ultrasound diagnostics. The ultrasound shows whether the liver is enlarged, whether there are benign or malignant tumors.
- CT - using computed tomography, the doctor sees a three-dimensional image of the body.
- Radioisotope scanning. Also called scintigraphy. Used for hepatitis is extremely rare.
- MRI. MRI with contrast clearly shows the bile ducts and their patency.
- Biopsy - taking a microscopic part of the liver for serological analysis.
Only when all data on liver function are obtained, the doctor makes any recommendations regarding diet, lifestyle and subsequent treatment. All recommendations are highly individual. Much depends on the severity of the disease.
Chronic hepatitis B with low activity, moderate andsevere. Symptoms
Hepatitis can be mild or severe. The disease often does not manifest itself in any way, flows asymptomatically. And the patient can find out about it by chance, after medical tests; if he prefers not to go to the doctors, he will not know until hepatomegaly begins - an increase in the liver in volume.
How does low-grade hepatitis manifest itself? There are symptoms of slight intoxication - general weakness and slightly elevated temperature. There is no nausea and vomiting. It happens that mild nausea occasionally appears, but the person does not take it seriously, believing that it is from food.
A form of moderate illness manifests itself in regular fatigue, which accumulates in the afternoon. Nausea is more pronounced, but there is no vomiting yet, sleep disturbances are also not detected. Frequent headache, and sometimes just a feeling of strange heaviness in the head. Bilirubin is already elevated, and yellow eyes can be seen in the mirror. There are no more serious anomalies in the physiology of the body yet. With these symptoms, it is important to take a test for the surface antigen of the hepatitis B virus. A positive result indicates the development of the disease.
What characterizes severe hepatitis B? There are such characteristic symptoms as tachycardia, dizziness, feeling before the eyes of black flies. Intoxication is pronounced, jaundice is present. Prothrombin index falls below 60%.
Fulminant hepatitis is also isolated - this is a super-acute form of the disease. Manifested in acute liver failure,liver cells begin to die en masse. The patient may fall into a prolonged coma and die.
Hepatitis in some cases has no other symptoms other than hepatomegaly. This term refers to the enlargement of the liver due to inflammation.
On palpation, the doctor finds that the liver is determined in the 6-8th intercostal space. The organ can protrude from under the costal margin from 0.5 to 8 cm. Almost all patients feel pain, pain is especially pronounced if inflammation of the bile ducts is observed at the same time.
But there are other situations. Hepatitis surface antigen in HBsAg is negative. What does it mean? This means that no symptoms should be expected. The patient's blood is clear of the virus.
Cost of analysis in Moscow
Different centers set their own pricing policy for services, so it's hard to say an unambiguous price. But in principle, an analysis for the surface antigen of the hepatitis B virus HBsAg is the cheapest of the entire series of tests for hepatitis B. In Moscow, donating blood to detect a marker will cost about 1000–1500 rubles.
Prevention
Hepatitis B is very difficult to treat, and it will take at least six months. And if the disease becomes chronic, then this is even worse because the patient will have to constantly take tests and monitor the condition of the liver. Knowing how dangerous it is, it is better to be vaccinated in advance and not try your luck. Manicure is best done at home, with your personal nail kit. Lead an intimate life deliberately, with one partner tested for infection.
It is desirable to eat optimally - do not overeat, do not eata lot of flour and fat, but you should not starve either. If a person is infected during an operation in a hospital or private dental clinic, poor nutrition will "help" the virus destroy the liver more quickly.
This is the only way to protect yourself from hepatitis. If a person is vaccinated, antibodies to hepatitis B surface antigen will last at least 10 years. And it will provide reliable protection.
After the expiration of 15 years, it is desirable to re-test for markers and antibodies. What could be the result? If the surface antigen of the hepatitis B virus is not detected, then everything is fine with your he alth.
Conclusions
When taking markers for hepatitis B, you need to know in advance what results you will encounter. Which numbers are considered positive and which are negative. If the surface antigen of the hepatitis B virus is positive - what does this mean? Your analysis showed that there are viruses in the blood. Perhaps this is a disease, but it can also be just a carriage. You should not be upset ahead of time, as the result can also be false positive.
For each antigen, the body produces antibodies. Immune complexes with antibodies are usually removed from the body in a natural way. But if the body is weak, the immune system cannot cope, and the disease becomes chronic.
What to do if the surface antigen of the hepatitis B virus is found? The norm for an adult is only 10 mU / ml. If your result is higher, then perhapsafter 14 days, the first symptoms of hepatitis will begin, such as jaundice, dark urine, headache, fatigue, tachycardia and others.
The most appropriate treatment tactic is to follow all the doctor's recommendations, control the level of surface antigen of the hepatitis B virus and eat right. People with hepatitis should not eat anything fatty or fried.
