When there is reason to believe that a person has contracted hepatitis, you can take an analysis for a surface antigen and determine the likelihood of jaundice in advance before these processes in the body start in full force.
Today, according to statistics, about 2 billion people around the world are already infected. And almost 350 million are sick with chronic hepatitis. In connection with this situation, doctors strongly recommend that all pregnant women take a test for hepatitis 2 times: when she gets 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 antigens must be determined in the blood and what is the role of their satellite antibodies. An antigen is a protein with the help of which an antibody is formed that can find the virus by its genome, capture and destroy it. This is how our immune system works. The purpose of the laboratory analysis is to detect viral antibodies in the blood in time, determine the stage of the disease, the type of virus and prescribe appropriate maintenance therapy. A person who receives an analysis in his hands should consult with a doctor about the results. For example, hepatitis B virus surface antigen is negative - what does it mean? And what are the reference values of the indicators given in the tests? All of this should be studied.
What is hepatitis B virus 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 the 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, the "antigen" is translated from English antibody generator - a manufacturer of antibodies. This article deals with the antigens and antibodies of the HBV hepatitis virus, therefore, information will be presented on those proteins that are parts of the hepatitis B virus.
Protein antigens are internal (nuclear) and surface. We will talk about them later.
The antigen-antibody system exists all the time that a person walks on 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, a person’s immunity is rather weak compared to the level of immune defense of previous generations, and we can’t imagine a normal life without medications.
Hepatitis B is currently being treated well. 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 virus surface antigen is detected? The norm for antigen is its absence. Since the presence of hbsag indicates infection.
How is antigen detected?
When and by whom was hepatitis B virus surface antigen discovered? It was discovered by an American research physician Baruch Blumberg. He made a breakthrough in understanding the mechanisms of origin of certain infections.
A few years later, during subsequent studies, Blumberg came to the conclusion that human antibodies are produced against a specific protein, namely the one contained in the envelope of the virus. Later, HBsAg, a surface antigen of hepatitis B virus, was detected in human blood without the virus. The antigen was purified and used to create a vaccine against the virus. Baruch Blamberg became a Nobel laureate 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.
Surface and nuclear HBV antigens
Hepatitis virion consists of a shell and personal DNA. The protein that is on the outside and makes up the capsid is called superficial, and the one that is inside the capsid is internal. There are two nuclear protein antigens - HBcAg, HBeAg.
The surface antigen of 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 strong protection 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, instruments in hospitals before surgery are not just wiped with alcohol, they are disinfected for a long time in special chambers using special methods. Virion is not destroyed by repeated freezing and thawing; it cannot be destroyed with weak solutions of disinfectants, for example, a formalin solution (0.1%) is not harmful to the virus.
Outside the host organism, the hepatitis B virus lives for 7 days. 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 purposefully attacks the liver. It penetrates the nucleus of hepatocyte and causes the cell to produce new viruses. A virus cannot reproduce without a carrier, and its entire “life” is a parasitic symbiosis. Due to the fact that viruses are inside the organ’s own cells, it is impossible to apply antibiotics to them.
Negative and positive antigen. What does it mean?
An antigen appears in the blood approximately 14 days before the end of the incubation period. During the analysis, it can already be detected, albeit in a small amount, but it is present. The incubation period itself in HBV hepatitis lasts from 4 to 12 weeks. It 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 saying that the hepatitis B virus antigen is positive, this is an occasion to think. This means that there is a virus in the blood and protective mechanisms are active. Even if a person does not yet feel unwell. It may be necessary to retake this analysis a second time.
Another result that occurs in the medical record is the surface antigen of the hepatitis B virus is negative. This result means that everything is in order and no HBV proteins were detected in the blood taken.
It is worth noting that the result is not always accurate. It can be false positive or false negative. Why? There may be several reasons for this:
- blood antigens to hepatitis C, D, E, but not B;
- hepatitis virus mutated;
- a person has become infected with a malignant type of virus;
- the person is a carrier of the "sleeping" virus;
- mixed hepatitis B + D;
- superinfection, when the sleeping virus B was already present in the body, and a person was also infected with the D. virus.
If the surface antigen of hepatitis B virus is doubtful, what is it preparing for and what to do with this 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 will be able to tell more, having on hand the results of certain studies.
Worst of all, if the virus has mutated. Then antibodies to the surface antigen of hepatitis B virus, which were developed due to vaccination, will not work. However, this is not all.
Antibodies to the surface antigen of hepatitis B virus
In addition to detecting HBsAg and HBcAg in the analyzes, antibodies HBsLg, HBcLgG and HbcLgM can also be found in blood samples. Which of these data follows? Antibodies circulating in the body indicate that inflammation is still present, either the person suffered 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 kind of protection.
In general, antibodies to the hepatitis B virus surface antigen appear several months after the detection of HBsAg or HBcAg. The norm of antibodies in the blood against a 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 hepatitis B virus surface antigen, is called seroconversion. This tipping point means 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” is stretched 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 in time.
Quantitative surface antigen. Norms
What are the norms for hepatitis B surface antigen? For each marker, norms are provided to adequately assess the numbers obtained by comparison, and so that doctors around the world can build on standard units of measurement.
So what should the hepatitis B virus surface antigen be like? The norm of the indicator is 10 mU / ml. However, you need to know other nuances. If the results of the analysis for hepatitis B surface antigen (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 indicated level, then the analysis is considered positive.
The numbers from 10 to 100 in the analysis are found in such cases:
- Acute HBV hepatitis is recovering.
- The vaccination was successful.
- The disease is chronic, but with low infectivity.
It happens that the test result in screening studies is dubious. Then a special verification analysis is done where the competitive ELISA method is used. During the test, the hepatitis B virus surface antigen is neutralized with specific antibodies. The result of such a study is many times more accurate.
Positive tests must be double-checked. When the analysis is repeated, it is necessary to take it under the same conditions and at the same time as for the first time.
Mutant forms of hepatitis and antigen
Like all compounds in the biological world, viruses undergo natural structural changes, that is, mutate. Since antigens respond to only one type of protein, they appear helpless in front of a mutated capsid. And modern tests cannot detect a mutated virus. Years of research are needed to find the formula for each virus and make a test for it. And those studies that are now have not yet yielded satisfactory results.
Who needs to be tested without fail?
Since the surface antigen of hepatitis B virus is very dangerous, this protein is a real poison for the liver, violates its functions and does not give any symptoms, it is advisable to take tests every couple of years. There are certain groups of people who just need to regularly donate blood for research:
- Those who work in a medical facility or in a public catering.
- Tourists visiting Africa.
- After contact with sick hepatitis.
- Asocial personalities.
- To those who are in prison.
- After hemodialysis.
- In order to become a blood donor.
Other citizens are tested for surface antigen at their discretion. Literally everyone has the risks of getting infected, especially young people who like to get tattoos on their bodies. If the tattoo artist does not sanitize the tools, the risk of getting infected is incredibly high. The same applies to dental offices with unskilled personnel and nail salons.
HBsAg Rapid Test
Determination of the surface antigen of hepatitis B virus is possible not only in laboratory 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 antigen in one drop of blood of a finger.
The role of macrophages in the destruction of the virus
Large immune cells called macrophages are involved in removing hepatitis B from the body. The HBV virus immediately tries to penetrate the hepatocyte cells - liver cells, and change its structure. If the immune system is strong, then its cells begin to kill both the damaged hepatocyte itself and those healthy cells that are nearby. In place of healthy cells, scar tissue grows. The HBsAg immune complexes determine extrahepatic tissue lesions by the virus, that is, they “catch” the virus that left the liver area and spread further with blood.
How is the liver cleansed of the virus? This happens only due to the death of the 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. Immunocomplex pathologies lead to diseases such as arteritis, glomerulonephritis and others.
A strong immune response of the body causes severe inflammation in the liver. Acute hepatitis can be very serious and require treatment in the infectious ward.
Antibody collection procedure
Blood on the surface antigen of hepatitis B virus is donated from the left hand. Be sure to have to fast for at least 6 hours. At the same time, 5 days before the analysis, you can 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 blood donation, just sit on a bench in the reception.
What does a health worker do? The hand above the elbow should be bandaged with a tourniquet. The needle is inserted neatly into the vein in the elbow, and blood flows through the needle into special medical hoses. Then the specialist takes the required amount of blood in a test tube.
Recommended adult vaccination times
If a small amount of antibodies to the hepatitis B virus surface antigen is detected in the blood, the doctor will insist on vaccination. This is the only way today to completely protect yourself from liver damage.
Health workers need a vaccine every 5–7 years. For other categories of the population, it is enough to get vaccinated once every 15 years. But there are special cases when doing this is prohibited:
- Vaccinations are forbidden to those who have recently had one of the strains of the hepatitis virus.
- People who are allergic or intolerant of the components of the vaccine.
- People over 50-55 years old.
- During the period of weakening of the body due to acute respiratory infections.
Before deciding on vaccination, it is advisable to consult your doctor. After the injection, a person may feel pain in the stomach, general weakness, body temperature often rises. If redness is observed at the injection site for several days, this is also a normal reaction to the vaccine.
Other virus markers
The determination of the hepatitis B virus surface antigen is only a small part of all the tests to be completed. This analysis provides little information.
The HBsAg serological marker is the primary and cheapest way to know your diagnosis in advance. But there are other virus markers that appear and disappear in strictly defined periods:
- HBeAg is in the blood from 1 week after the appearance of HBsAg, decreases after 20-40 days. This is a 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 is the nuclear core antigen of HBV. Its presence means that the person is either sick now or has had an acute infection and is a carrier of antibodies to HBV. It is revealed exclusively during morphological studies.
- LgM anti-HBc antibodies (class LgM) to a nuclear antigen. Antibodies are 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 the hepatitis B nuclear antigen. Present in the body 7-14 days after HBsAg. This is a very important diagnostic indicator. Provides a clearer picture of what happens if HBsAg is negative. May indicate post-vaccination antibodies or a previous inflammatory process in the liver.
Markers such as LgG and nuclear antibodies remain in human blood all their lives, others disappear as hepatitis develops in the body.
What can all these markers say to doctors? After examining all the indicators, the specialist renders his verdict. The results may be as follows:
- Chronic active hepatitis B.
- Acute hepatitis (mutant, wild or normal type).
- Just a carriage.
- Latent chronic infection.
- Resolved acute hepatitis.
- — .
But you do not need to think that any one marker will give all the answers to the questions. The diagnosis is made after considering many tests, the general functional state of the liver and patient complaints. If a person is simply a carrier of the virus, there is no need to treat it. In an inactive form, it does not harm the body.
Diagnosis of the liver
The purpose of additional diagnostics is to determine the degree of liver dysfunction. By the color of the sclera of the eyes and urine, only that the level of bilirubin has become higher than normal is determined. Other impaired liver function cannot be visually observed.
What research needs to 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. So the condition of the patient with hepatitis is controlled.
- Coagulation system control. Be sure to establish the level of prothrombin production, which is involved in the process of blood coagulation after causing damage to the body.
- Studies of liver function such as its participation in protein metabolism. The parenchymal organ is involved in the production of such proteins: globulin, fibrogen and albumin.
- The study of alkaline phosphatase. The analysis is needed to detect metastatic tumors with a long course of moderate and severe chronic hepatitis.
- Study of the excretory function of the liver. That is, how much the body retained the ability to cleanse the blood of toxins. This is important for determining the chronic stage of hepatitis B.
- And also the level of cholinestasis is checked.
Here are the diagnostic tools that are used to study the liver:
- Ultrasound diagnostics. An ultrasound scan shows whether the liver is enlarged, whether there are benign or malignant tumors.
- CT - with the help of computed tomography, the doctor sees a three-dimensional image of the organ.
- Radioisotope scanning. Also called scintigraphy. It is used extremely rarely for hepatitis.
- MRI Using MRI with contrast, the bile ducts and their patency are clearly visible in the images.
- A biopsy is a serological analysis of the microscopic part of the liver.
Only when all the data on liver functions are obtained, does the doctor give any recommendations regarding diet, lifestyle and subsequent treatment. All recommendations are extremely individual. Much depends on the severity of the disease.
Chronic hepatitis B with low activity, moderate and severe. Symptoms
Hepatitis can occur both in mild and severe. The disease often does not manifest itself in any way, it flows asymptomatically. And the patient may learn about it by chance, after medical tests; if he prefers not to contact doctors, then he won’t know until hepatomegaly begins - an increase in the volume of the liver.
How does hepatitis with low activity manifest itself? Symptoms of slight intoxication are present - general weakness and slightly elevated temperature. There is no nausea or vomiting. It happens that mild nausea occasionally appears, but a person does not take it seriously, believing that it is from food.
The form of the disease of moderate severity is manifested in regular fatigue, which accumulates in the afternoon. Nausea is more pronounced, but vomiting is not yet, sleep disturbances are also not detected. Frequent headache, and sometimes just a feeling of a 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. With these symptoms, it is important to take a test for hepatitis B surface antigen. A positive result indicates the development of the disease.
What is characterized by severe hepatitis B? There are characteristic symptoms such as tachycardia, dizziness, sensation of black flies in front of the eyes. Intoxication is very pronounced, jaundice is present. The prothrombin index falls below 60%.
Fulminant hepatitis is also isolated - this is an over-acute form of the disease. It manifests itself in acute liver failure, liver cells begin to die in large numbers. The patient may fall into a prolonged coma and die.
Hepatitis in some cases does not have other symptoms than hepatomegaly. This term means liver enlargement due to inflammation.
On palpation, the doctor discovers that the liver is determined in the 6-8 intercostal space. The organ can protrude from under the costal margin from 0.5 to 8 cm. Almost all patients experience painful sensations, pain is especially pronounced if inflammation of the bile ducts is observed at the same time.
But there are other situations. Hepatitis B 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.
Analysis cost in Moscow
Different centers set their pricing policy for services, so it’s hard to say an unequivocal price. But in principle, an analysis of the surface antigen of hepatitis B virus HBsAg is the cheapest of the entire series of tests for hepatitis B. In Moscow, donating blood for detecting a marker will cost somewhere between 1,000 and 1,500 rubles.
Prevention
It is very difficult to treat hepatitis B, and it will take at least six months. And if the disease goes into a chronic form, 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 to test fortune. Manicure is best done at home, with your personal set of nails. To lead an intimate life deliberately, with one partner tested for infection.
It is desirable to eat optimally - do not overeat, do not eat a lot of flour and fat, but you should not starve either. If a person is infected during an operation in a hospital or in a private dental clinic, poor nutrition will “help” the virus destroy the liver faster.
This is the only way to protect yourself from hepatitis. If a person is vaccinated, antibodies to the hepatitis B surface antigen will last at least 10 years. And this will provide reliable protection.
After 15 years, it is advisable to re-analyze for markers and antibodies. What could be the result? If the surface antigen of hepatitis B virus is not detected, then everything is fine with your health.
conclusions
When passing markers for hepatitis B, you need to know in advance what results you will encounter. Which numbers are considered positive, which are negative. If the hepatitis B virus surface antigen is positive, what does it mean? Your analysis has shown that viruses are present in the blood. Perhaps this is a disease, but it may just be carriage. It is not worth it to be upset before the time, as the result can also be false positive.
The body produces antibodies to each antigen. Immune complexes with antibodies are usually excreted naturally from the body. But if the body is weak, the immune system can not cope, and the disease becomes chronic.
What should I do if a surface antigen of hepatitis B virus is detected? The norm for an adult is only 10 mU / ml. If your result is higher, then perhaps in 14 days the first symptoms of hepatitis will begin, such as jaundice, dark urine, headache, fatigue, tachycardia and others.
The most suitable treatment tactic is to follow all the doctor’s recommendations, control the level of hepatitis B virus surface antigen and eat right. People with hepatitis should not eat anything fatty or fried.