Hepatitis B

Viral hepatitis B is an infection that is the most common cause of acute and chronic liver pathologies, cirrhosis and hepatocellular cancer, in addition, HBV provokes most biliary dysfunctions. The main danger of the virus is that, according to WHO experts, there are currently about 300,000,000 diagnosed carriers of the infection in the world, it is logical to assume that there are many more unexamined virus carriers.

Epidemiology of hepatitis B

Until recently, hepatitis B had several name variants – serum, syringe, parenteral. These definitions really explain the main route of transmission of the virus into the blood: the infection enters the body through damaged mucous membranes and microdamage to the skin. The HBV marker was first isolated half a century ago, in 1963, since the antigen was found in the blood of the indigenous people of Australia, who suffered from hepatitis en masse, it was called "Australian". Seven years later, a full-fledged virus was identified, which paved the way for a new nosological form to appear in the classification of infections – the hepatitis B virus (HBV).

The epidemiology of hepatitis B is characterized by a unified source and route of infection. HBV can only be transmitted from an infected person parenterally (through damaged internal mucous membranes or external skin); there are several possible routes of virus penetration: 1.

The natural way:

• Contact, when the virus penetrates the bloodstream through microtraumas, cracks in the skin, mucous membranes. This occurs when sharing hygiene items intended for personal use - a razor, toothbrush, scissors. An item belonging to a virus carrier poses a potential threat to others.
• Vertical transmission – intrauterine infection of the fetus from an infected mother, infection of the child during passage through the birth canal, or infection during care (chewing food for the baby, close physical contact with an infected mother, etc.). The virus is not transmitted through breast milk.
• Sexual transmission, both during heterosexual and homosexual sexual contacts.

Artificial route of infection:

• Medical procedures – injections, drip infusions, blood transfusions.
• Transplantation of donor organs and tissues.
• Drug addiction (injection).

The virus requires a certain environment to spread – blood, seminal fluid, saliva, urine, vaginal discharge, thus the route of transmission of HBV is almost identical to the variants of HIV infection. The epidemiology of hepatitis B is one of the most alarming problems for the global health system. Its total prevalence has decreased somewhat over the past 5 years, thanks to the introduction of vaccination rules, but the main sources and carriers of the virus are still people who use injection drugs and people who lead a promiscuous lifestyle. Vaccines against these two troubles have not yet been invented, so hepatitis B continues to take more than 2,000,000 lives annually.

The risk groups for hepatitis B infection include the following categories of people:

• Injection drug addicts.
• People who prefer non-traditional sexual orientation.
• People who lead a promiscuous sexual lifestyle (unprotected sex).
• A circle of people who have constant close contact with an HBV patient or virus carrier.
• Patients who require injection therapy or transfusion (intravenous drip administration of the drug), hemotransfusion (blood transfusion), transplantation, hemodialysis.
• Newborns whose mothers are carriers of the infection or have acute or chronic hepatitis B.
• Medical personnel who are constantly involved with blood (surgeons, dentists, manipulation nurses, laboratory technicians).

Hepatitis B - Epidemiology

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Cause of Hepatitis B

The etiology (cause) of hepatitis B is the causative agent of the disease, the hepatitis B virus (HBV) from the Hepadnaviridae group, which has DNA in diameter reaching 45 nanometers, with a lipoprotein membrane and a complex, double antigen structure. Due to this, the HBV virus is extremely resistant to the effects of the environment in terms of temperature or disinfection. The causative agent of hepatitis B can remain viable for about 10 years at room temperature, it is active in the bloodstream for many years, sometimes without showing any signs of itself. The virus can be found on untreated injection needles, dental instruments and even on bed linen containing elements of infected blood. The hepatitis antigen can be destroyed using an autoclave if you process infected items in it for 45 minutes at a high temperature - up to 120 degrees. The method of dry sterilization for an hour also works on the virus. In addition, disinfectants that can inactivate the HBV virus include formalin, hydrogen peroxide, phenol, or chloramine. Despite existing methods of neutralizing the antigen, the virus is constantly mutating. New mutant strains are resistant to many standard disinfection procedures.

The cause of hepatitis B is the penetration of the virus into the blood through microtraumas on the skin and mucous membranes. The pathogen enters the liver cells through the bloodstream and begins a gradual replication in hepatocytes, without having an obvious pathological effect on them. Hepatocytes are destroyed not by the virus itself, but by the "fight" of the immune system with the pathogen. Cytolysis (the level of pathological damage) is directly related to the activity of the immune system and the structure of the virus itself, its variant. The severity of the disease and the speed of its development are determined by the activity of T-lymphocytes on hepatocytes infected with the virus. A necrobiotic process gradually develops in the liver, and after months, and more often years, the entire biliary system of the body is included in it - bile ducts, gall bladder, spleen.

Hepatitis B - Causes

Symptoms of Hepatitis B

Clinical manifestations of hepatitis B depend on the form of the disease – chronic or acute. It is believed that the acute form of HBV is more common, which is characterized by signs of jaundice and pronounced cytolysis.

The acute form of infection has classic stages, typical for all types of hepatitis:

• Incubation.
• Pre-icteric period.
• Jaundice.
• The recovery period is convalescence.
• Hepatitis B - acute form.

The incubation stage of acute hepatitis B lasts from 1.5 months to six months. The pre-icteric period lasts about a week and is characterized by signs of intoxication of the body - dyspepsia, weakness. The patient is constantly sleepy, dizzy, joints hurt and ache. Body temperature, as a rule, is not elevated or increases slightly, without causing a fever. During the pre-icteric period, the spleen and liver begin to increase in size, urine acquires a characteristic dark shade, feces are depigmented. If a person undergoes a medical examination, or is examined specifically for hepatitis, at this stage, laboratory tests show the presence of urobilinogen in the urine, bile pigments, and in the blood serum - the HBsAg antigen and increased activity of ALT (alanine aminotransferase).

It is impossible not to notice the symptoms of hepatitis B during the icteric period. The duration of the icteric stage varies from 14 to 40 days. This is the peak of the disease, which is accompanied by yellowing of the skin, sclera of the eyes, hard palate and oral mucosa. Developing intoxication is manifested by severe weakness, headaches, insomnia, nausea and loss of appetite. The right side of the epigastrium may hurt, the disease at this stage is characterized by pain on the right in the hypochondrium after each meal. Skin itching, cardiac symptoms - systolic murmur, bradycardia appear. Despite the fact that the liver decreases in size after pathological enlargement, its dysfunction and insufficiency develop due to cell necrosis and organ compaction.

Symptoms of hepatitis B at this stage can manifest in waves - sometimes fading, sometimes recurring, which indicates that the disease is becoming chronic.

The recovery stage lasts at least one year, although the main signs of hepatitis may disappear after two or three months. The asthenovegetative state, accompanied by periodic pain on the right side of the hypochondrium, lasts the longest.

It should be noted that HBV also has latent, anicteric forms, which are characteristic of the chronic course of the pathological process.

The most serious symptoms of hepatitis B are acute liver failure and hepatic encephalopathy. These syndromes are characterized by pronounced neurological signs, skin itching and rashes, a drop in blood pressure, tachycardia, and a typical "liver" odor from the mouth.

The most dangerous is hepatic encephalopathy, which develops in stages:

1. Initial precoma – delirious states, insomnia, dizziness, cognitive impairment, tremor of the limbs, uncontrollable vomiting, skin itching and rashes. All these symptoms of hepatitis B develop against the background of jaundice.
2. Precoma in the second stage – impaired coordination of movements, confusion, psychomotor agitation, which alternates with adynamia and weakness. Tremor is noticeable not only in the limbs, but also in the lips and tongue. Tachycardia develops, arterial pressure changes sharply from low to significantly high, up to hypertensive crises. The liver at this stage is reduced in size.
3. Coma is a loss of consciousness with preserved basic reflexes (breathing, swallowing) and reactions to intense stimuli. The reflexes of urination and defecation are impaired. The syndrome of an empty right hypochondrium develops, when the liver is not determined by palpation.
4. Deep coma - consciousness is completely lost along with all reactions and reflexes.

Liver coma is most often the main consequence of a complex form of hepatitis B – fulminant. As a rule, the patient dies within 2-3 weeks.

Hepatitis B - Symptoms

Hepatitis B - chronic form

Symptoms of chronic hepatitis B are a sluggish inflammatory process in the liver that lasts for years. This disease is clinically poorly manifested, the only sign indicating hepatitis may be hepatomegaly - an increase in the size of the liver, the spleen also increases.

Progression of the disease is possible with trigger conditions - concomitant inflammatory infections. In this case, hepatitis B manifests itself as transient skin itching, the appearance of spider veins on the skin, palmar erythema (red palms), nosebleeds. Jaundice may be visible only at the stage of a minor exacerbation of the disease, dyspepsia and a slight increase in body temperature are also possible. Such a sluggish course of the disease is dangerous because the pathological process lasts for many years, destroying liver cells and provoking the development of cirrhosis.

Chronic hepatitis B

Diagnosis of hepatitis B

Hepatitis B is most often diagnosed in people who have direct contact with already infected individuals, as well as in those who are at risk of infection. However, there is no medical examination for hepatitis B, patients and carriers of the virus are rarely examined on their own, so hepatitis B is diagnosed in hospital settings when the disease progresses.

HBV indicators are HBs-antigen, bilirubin level in the blood, transaminase level. Diagnostic tests have the following markers, the level of which determines HBV:

• Antigen HbsAg (surface antigen).
• HBeAg antigen (antigen that replicates in the hepatocyte nucleus).
• ALT.
• HBV DNA.
• Antibodies to antigens.

Markers are determined using the PCR method – polymerase chain reaction. The diagnosis of hepatitis B with clinically manifested symptoms is established quickly, the main task of diagnostic measures is to differentiate the virus and its strains. Also of great importance are anamnestic data, which allow to clarify the onset of the disease and the route of infection.

Hepatitis B - Diagnosis

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Treatment of hepatitis B

Mild viral hepatitis B is treated mainly by following a gentle diet (table No. 5 according to Pevzner), limiting physical and motor activity, taking hepatoprotectors and vitamins.

Treatment of hepatitis B, which is more severe, involves detoxification therapy, taking enterosorbents, infusion of nutritional preparations, water-salt physiological solutions, including Hemodez, Ringer's solution, glucose. Metabolic and restorative therapy is indicated after detox and neutralization of the main symptoms, it includes hepatoprotectors, enzymes, vitamins and microelements. In addition, a gentle diet and plenty of fluids are required.

A severe condition is treated by increasing the volume of detoxifying drugs, they are administered up to 3 liters per day. Prednisolone or other glucocorticosteroids, antispasmodics, diuretics, and, less often, antibiotics in the presence of a concomitant infection are also prescribed.

Treatment of hepatitis B in a pre-comatose state (acute liver failure, encephalopathy) involves a complex of intensive therapy, and sometimes resuscitation.

The main drug in the treatment of many types of hepatitis, as well as in the therapy of hepatitis B, is alpha-interferon. Its antiviral and immunomodulatory action allows achieving good results, provided that treatment is started in a timely manner.

If viral hepatitis is mild and does not require hospitalization, then therapy is carried out at home and complies with the following recommendations:

• Drink plenty of fluids regularly to speed up detoxification and prevent dehydration.
• Diet according to Pevzner No. 5, which must be followed for at least six months.
• Refusal of self-medication and prescription of medications. You cannot experiment with taking antibiotics and even hepatoprotectors, so as not to aggravate the course of the disease. Drug therapy is prescribed only by a doctor.
• A categorical refusal of alcohol, including beer and low-alcohol drinks.
• Limitation of physical and motor activity. The gentle regime should last at least 2-3 months.

It should be noted that the treatment of hepatitis B in severe conditions, in the terminal stage of the chronic form, may also involve surgical intervention. It is believed that hepatocellular carcinoma is not amenable to drug therapy and requires a donor liver transplant.

Hepatitis B - Treatment

Prevention of hepatitis B

It is known that the main route of spread of the hepatitis B virus is parenteral. Therefore, ensuring sterile conditions for parenteral administration of drugs should neutralize the spread of the virus. Indeed, the measures that include the prevention of hepatitis B are partially controlled by medical workers. However, the other half of the problem requires general discussion, state programs and a total fight against the global systemic epidemic - drug addiction.

For 30 years, the medical world has been taking all necessary measures to prevent iatrogenic factors of hepatitis B infection:

• Dispensary examinations of contact persons.
• Strict control and testing of donor blood.
• Widespread use of disposable syringes, instruments, and gloves.
• Strict control over the timely sterilization of reusable instruments and devices, as well as the processing of household items and linen in hospitals.

More systemic prevention of hepatitis B is vaccination, for which various types of vaccines against the HBV virus are used. Vaccination is carried out in three stages, and the primary vaccination is given to newborns within the first 10-12 hours after birth. Immune protection is guaranteed for 5 years, but most often lasts 10 years or more. Passive vaccination is carried out in cases of suspected infection of adults. The introduction of immunoglobulin against hepatitis B (Neohepatect or analogue) is effective no later than two days after possible infection, and then vaccination is carried out according to the standard scheme.

Also, prevention of hepatitis B requires people to follow simple rules. Following these recommendations, you can reduce the risk of infection by 90%.

• Protected sexual intercourse – the use of condoms and other methods of preventing infection, including STDs (sexually transmitted diseases).
• Use of disposable sterile instruments, syringes for injections and other medical procedures.
• A responsible and thoughtful approach to the desire to get a tattoo, including cosmetic ones.
• Use of personal, individual tools for nail treatment, shaving.
• When planning a pregnancy, a medical examination is mandatory: you need to take a test for the presence or absence of the hepatitis B virus.

Prevention of hepatitis B

Hepatitis B Vaccination

The main reliable method of prevention, which guarantees long-term protection against the virus, is considered to be vaccination against hepatitis B. In many developed countries, a state program is being implemented to counter the HBV epidemic. Vaccination against hepatitis B (HBV) is mandatory for all newborns, as well as for those who have close contact with infected persons. The HBV vaccine is included in the mandatory list of childhood vaccinations in our country. This is explained by the fact that infants have not yet developed immunity and the risk of the disease developing into a chronic form with primary infection is 100%. In addition, the vaccine administered in the first hours after birth guarantees stable protection of the baby from HBV for many years. Vaccination against hepatitis B, carried out according to all the rules, creates a reliable immune response against the virus for 10-15 years.

It should be noted that the vaccination program was introduced not so long ago, and accordingly the adult population was not covered by vaccinations. That is why WHO strongly recommends vaccination to the following categories of people:

• Patients with chronic diseases who require regular therapy with injections of drugs.
• For patients who require blood transfusion.
• For patients undergoing hemodialysis.
• For healthcare workers who are in constant contact with infected patients or blood products.
• For preschool children.
• All persons who come into contact with infected people in everyday life.
• For people who lead an active sexual life, including those of non-traditional orientation.
• For people who are going on a trip to regions with a high epidemiological threshold.
• For patients suffering from chronic diseases of the biliary system.

Vaccination against hepatitis B is carried out by injection of the drug into the upper thigh of children under 3 years of age, and the vaccine is administered to older children and adults in the shoulder. The only contraindication is a rare type of allergy to baker's yeast, and the vaccine is not administered to premature babies whose weight does not reach 2 kilograms.

Hepatitis B prognosis

Many patients infected with the HBV virus are faced with the question of how alarming the prognosis of hepatitis B is. Clinical practice shows that with timely diagnosis and treatment, half of the patients recover, especially if the disease is acute. The most severe outcome is possible with a fulminant course of hepatitis B, when fatal outcomes make up about 85-90% of the total number of HBV-infected people.

The prognosis for chronic hepatitis B is also considered unfavorable. Chronic hepatitis most often ends in liver cirrhosis - up to 20%, and in 5-7% - liver carcinoma.

The prognosis for hepatitis B for asymptomatic carriers of the infection is favorable; such people need to undergo routine medical examinations, monitor their health, and follow all recommendations to prevent the spread of the virus.

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