Hepatitis D

Hepatitis D (hepatitis delta, hepatitis B with delta-agent) - viral hepatitis with a contact mechanism of the pathogen transmission caused by a defective virus, the replication of which is possible only in the presence of HBsAg in the body. The disease is characterized by severe course and unfavorable prognosis.

Hepatitis D is a type of HBV (viral hepatitis) group and is called delta infection. For the first time, virus D was differentiated as a separate component in 1977 during an unprecedented outbreak of HBV (virus B) in Southern Europe. The virus D is considered defective, as it does not multiply on its own, it needs the presence of HBV for distribution. Delta infection (HDV) is resistant to external factors, but can be treated with alkaline or acidic media. The disease is very difficult, because it develops against the background of already infected hepatitis B.

To date, Hepatitis D has been identified in two forms:

1. As a co-infection (co-infection), developing simultaneously with infection with the virus B.
2. As a superinfection, which develops after infection with virus B (antigen HBsAg) as a layering.

The HDV virus has its own RNA genome, is transmitted exclusively by the hematogenous pathway and can affect only those who are already infected with the hepatitis B virus. A similar pathological combination often results in necrotic liver cells, cirrhosis.

ICD-10 codes

• 816.0. Acute hepatitis B with delta-agent (coinfection) and hepatic coma.
• 816.1. Acute hepatitis B with delta-agent (coinfection) without hepatic coma.
• B17.0. Acute delta (super) -infection of hepatitis B virus.

Epidemiology of hepatitis D

HDV is defined as an incomplete, defective satellite virus. With only RNA, the virus needs an outer shell for replication. That's why he uses the hepatitis B virus, which has its own DNA. On the one hand, it forms hepatotropic pathogenic properties of the delta infection, on the other hand it allows it to quickly enter the liver cells. Despite the fact that genotypes of hepatitis delta virus - HDV have been identified relatively recently, one of them has already been well studied. Genotype I affects people in the US and European countries, other genotypes are not yet classified.

The epidemiology of hepatitis D (HDV) is characterized by the main pathway of spread - artificial, most often as a result of injections, medical manipulation. There is also a natural way of infection, which is similar to the spread of hepatitis B. Hepatitis D is not capable of provoking hepatitis without self-replication by the HBV virus, so the combination of HDV and hepatitis B most often ends with liver cirrhosis (70% infected).

Statistics say that to date in all countries of the world, carriers of the hepatitis B virus are at least 350 million people, of whom about 5 million are infected and delta hepatitis - HDV. The highest percentage of infection is observed in chemically dependent people (drug addiction), and it has also been clinically proven that the hepatitis D virus is rapidly reactivated in HIV-infected people.

Epidemiology of hepatitis D is characterized by territorial endemicity for the population of southern European countries, for some northern states of America and for South America, where most cases of co-infections are diagnosed, however, in the form of superinfection, hepatitis D is most often found when injecting infection everywhere. Also at risk are people who are sick with hemophilia, diseases requiring transfusion therapy. Among homosexual carriers of the genotype HBsAg, delta-hepatitis is rare.

Hepatitis D - Epidemiology

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Causes of hepatitis D

The cause of hepatitis D is human infection with delta virus (HDV), which is not an independent pathogen. The genotype of hepatitis D is not capable of replication without the presence of the hepatitis B virus in the body, since it consists of single-stranded RNA and delta antigen. Self-reproduction in the hepatocyte (liver cell) is possible only in the presence of DNA-containing HBV.

In the interaction of these two viruses there are two options: 

Simultaneous entry into the body or co-infection.

Inflammation of the hepatitis D virus on the DNA envelope of the hepatitis B virus or superinfection.

If the cause of hepatitis D is the first option, the disease is extremely difficult, but modern medicine tries to curry it with the help of intensive medication.

The second variant is more unfavorable: hepatitis develops rapidly, proceeds in an acute form and often ends with cirrhosis or carcinoma.

The cause of hepatitis D is that a person due to pathological diseases or a lifestyle is at risk. The main categories that are at risk of infection with HDV:

• Patients with hemophilia.
• Patients needing transplantation.
• Chemically dependent people (drug addiction).
• Homosexual relations.
• Children with infected mothers (vertical transmission route).
• Patients needing hemodialysis.
• Medical workers, by virtue of the profession having contact with blood materials.

Hepatitis D - Causes and pathogenesis

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Symptoms of hepatitis D

The incubation of the HDV virus can last from 3 weeks to several months, and the symptoms of hepatitis D also depend on the duration of the incubation period. Two clinically manifested periods are characteristic: pre-jaundice and icteric, which differ little in symptomatology from signs of hepatitis B.

• Acute form of the disease 
• Pre-zheltushny period, which is superinfection (stratification) is shorter than with co-infection, co-infection (lasts no more than 7 days): 

1. Gradual decrease in activity, fatigue, drowsiness.
2. Decreased appetite, body weight loss.
3. Periodic febrile state.
4. Chronic feeling of nausea.
5. Subfebrile body temperature.
6. Pain, aches in the joints.

• Jaundice period: 

1. Staining of the skin, sclera of the eyes in a yellow shade (saffron).
2. Staining of feces in light color (depigmentation).
3. Dark urine (the color of dark beer).
4. Urticaria rash.
5. Obviously expressed pain on the right, in the hypochondrium.
6. Objectively, with palpation - an increase in the size of the liver and spleen.
7. Signs of body intoxication.
8. Dizziness.
9. Nausea and vomiting.
10. Superinfection is characterized by a sharp increase in body temperature.

Hepatitis D in acute form rarely ends in complete recovery, even with adequate treatment, it turns into a chronic form.

Symptoms of hepatitis D, chronic form: 

• Gradual staining of the skin in a yellow tint.
• Hemorrhages - microscopic subcutaneous hemorrhage (asterisks).
• Hepatomegaly, splenomegaly.
• Nasal bleeding.
• Hypersensitivity, bleeding.
• Increased vascular permeability, bruises.
• Constant febrile state with body temperature in the range from 37, 5 to 39 degrees without signs of SARS, acute respiratory infections.
• Ascites, puffiness.
• Chronic pulling pain on the right side of the hypochondrium.

Hepatitis D - Symptoms

Diagnosis of hepatitis D

The main diagnostic method in determining HDV is a serological blood test. Diagnosis of hepatitis D in acute form reveals a specific immunoglobulin - anti-HDV-IgM, as well as the HD antigen along with quite expected hepatitis B markers. In a second study, the results show a significant increase in IgG titers. In the serum there is a markedly elevated level of (two-phase) aminotransferases (ALT, AST).

Diagnosis of hepatitis D in chronic form determines the presence of a specific immunoglobulin anti-HDV-IgM. The method of polymerase chain reaction (PCR) confirms the replication (self-reproduction) of the virus, when quantitative and qualitative parameters of delta-RNA are determined.

Also, according to the indications, a study of the biological material of the liver can be carried out-a biopsy, as a result of which it is possible to detect the RNA of the virus and antigens in the cells-hepatocytes. Diagnosis of hepatitis D is necessary for a clear differentiation of the genotype and type of the virus, because the choice of treatment option depends on this.

Hepatitis D - Diagnosis

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Treatment of hepatitis D

Treatment of hepatitis D is threefold: 

1. Antiviral treatment (alpha interferon).
2. Symptomatic therapy (hepatoprotectors, enzymes, vitamins).
3. Dietotherapy (diet number 5 according to Pevzner.

The main method of HDV treatment is IFN-therapy - interferon therapy. Also, treatment of hepatitis D involves basic detoxification, hepatoprotective therapy, which are identical to the therapeutic strategy for infection with the hepatitis B virus.

Treatment of hepatitis D with the help of interferon (alpha interferon) is the use of sufficiently large doses of the drug - up to 10.000.000 IU per day. Introduction is conducted every two days (three times during the week) for a long time - at least one year. This method can reduce symptoms, but the tolerability of intensive therapy with interferon in patients with co-infection is much worse than with the presence of a separate HBV virus.

As a rule, treatment is done out-patient, hospitalization is necessary only for biopsy or in case of urgent dehydration, detoxification with the help of an infusion method.

Hepatitis D - Treatment

Prevention of hepatitis D

Prevention of hepatitis D infection is possible only through preventive measures that prevent human infection with hepatitis B virus, since HDV can not self-reproduce itself, it needs HBV DNA. To date, it is believed that vaccination against hepatitis B is a fairly reliable guarantee that the human body produces a persistent immune defense against HBV and, accordingly, against hepatitis D.

Also the prevention of hepatitis D is a whole complex of measures aimed at informing the population about the danger of infection. The rules for the sterility of medical instruments, instruments, checking the sterility of donor blood, drugs containing biological material, donor biological materials, safe, protected sexual contacts are the main measures that help reduce the incidence of hepatitis infections in principle. In addition, people who are already infected with HBV should undergo regular check-ups and take responsibility not only for their own health, but also understand that they are a source of potential infection of surrounding people. Prevention of hepatitis D is also a prevention of injection contamination with the use of narcotic drugs, but this problem is so global that its description requires a separate information space.

Vaccination against hepatitis D

The main way to prevent infection with the HDV virus is vaccination against hepatitis D.

Currently, no specific vaccine against the delta virus has been created, which is explained by the high degree of reliability of vaccination against hepatitis B. Worldwide, it is statistically and clinically proven that those who are vaccinated against HBV have a stable immune defense and antibodies to HBsAg. In addition, even with late vaccination and the presence of the virus in the body, the disease in patients is much easier and has a relatively favorable prognosis.

97% of people who have been infected with hepatitis B or who received a timely vaccination against this infection are not infected with delta virus. Thus, vaccination against hepatitis D is primarily a planned vaccination against hepatitis B, the first of which is done within 12 hours after birth. While the vaccine against HDV is not created, the only way to avoid infection with the delta virus is timely early vaccinations and compliance with preventive measures.

Hepatitis D prognosis

The prognosis of hepatitis D is particularly unfavorable for people who suffer from chemical dependence. Injecting drug users are not only the first risk group, but also the highest percentage of deaths, according to statistics provided by WHO, about 65%. Mortality is caused by the rapid development of liver failure and extensive necrotic processes. Mass necrosis of hepatocytes when combined infection (co-infection) is extremely difficult to stop. In addition, the unfavorable prognosis of hepatitis D is due to the fact that often the HDV clinic appears already in the late period against the backdrop of a chronic hepatitis that lasts for years. Delta virus is a trigger factor to the rapid development of exacerbation, when a necrotic process takes the liver in just a few days.

The prognosis also depends on the variants of the course of the disease: 

1. Chronic, latent form. In this form, hepatitis can develop from 10 years or more, gradually depleting the reserve and protective properties of the body.
2. Rapidly progressive form. The disease develops within 1-2 years.
3. Wavy course of the disease - from 5 to 10 years.

Virtually all chronic forms of hepatitis D result in cirrhosis of the liver.

Oncoprocess in patients with hepatitis D is extremely rare, it is obvious that the progression of the disease with superinfection or co-infection does not give place and time for the development of hepatocellular cancer. Most often, patients die before the process passes into the malignant stage.

The most favorable prognosis for those who received late vaccination, it helps to reduce the severity of symptoms and significantly increases the patient's chances of relative recovery.