Viral hepatitis D
Viral hepatitis D (Delta hepatitis) is an infectious liver disease, coinfection or superinfection of viral hepatitis b, significantly impairs its course and prognosis. Viral hepatitis D refers to a group of transfusion hepatitis.
Characterization of the pathogen
Hepatitis D is called RNA-containing virus, which is the only currently known representative of the “wandering” of the genus Deltavirus, which is characterized by poor self-forming protein for replication and uses a protein produced by the virus of hepatitis B. Thus, the causative agent of hepatitis D is a virus-satellites and is found only in combination with hepatitis B.
Hepatitis D is extremely stable in the environment. Heating, freezing and thawing, exposure to acids, nucleases and field of glycosidase inhibition does not have a significant impact on its activity. Reservoir and source of infection are sick combined form of hepatitis b and D. the Contagiousness is especially pronounced in the acute phase of the disease, but patients pose the risk of epidemic during the whole period of circulation of virus in the blood.
The mechanism of transmission in viral hepatitis D is parenterally, a prerequisite of transmission of the virus is the presence of active hepatitis b virus hepatitis D Virus integrated into its genome and enhances the ability to replicate. The disease may be an infection when the hepatitis D virus is transmitted simultaneously with either a superinfection, when a pathogen enters the body is already infected with hepatitis B. the Most significant risk of infection during the transfusion of blood from infected donors, notable epidemiological significance of surgical intervention, traumatic medical procedures (e.g. dentistry).
Hepatitis D virus is able to pass through the placental barrier, can be transmitted sexually (large spread of the infection among individuals who are prone to promiscuity, homosexuals), which has in some cases family the spread of the virus suggests the possibility of transmission by contact-household. To viral hepatitis D patients are susceptible to viral hepatitis b and carriers of the virus. Especially large susceptibility of individuals, which revealed chronic carriers of HBsAg.
Symptoms of viral hepatitis D
Viral hepatitis D complements and complicates the course of hepatitis B. the Incubation period coinfection significantly reduced in 4-5 days. Incubation of superinfection lasts between 3-7 weeks. Predzheltushnogo the period of hepatitis b occurs is similar to that for hepatitis b, but has a shorter duration and a more rapid course. Superinfection can be characterized by early development of edematous-ascitic syndrome. Icteric period runs as well as for hepatitis b, but the bilirubinemia more pronounced, often show signs of bleeding. Intoxication in icteric period of hepatitis D is significant, prone to progression.
Co-infection occurs in two phases, the interval between the peaks of clinical symptoms which is 15-32 days. Superinfection often difficult differential diagnosis, because it is similar to those for hepatitis B. it is characterised by the speed of deployment of the clinical picture, fast chronic process, hepatosplenomegaly, impairment of protein synthesis in the liver. Recovery takes much more time than in the case of hepatitis b, residual fatigue may persist for several months.
Chronic viral hepatitis D is characterized by the specific symptoms manifested similar to chronic hepatitis of other etiology. Patients concerned about General weakness and fatigue, the occasional “unexplained” episodes of fever with chills without catarrhal symptoms, accompanied by subjectual and jaundice. On the skin formed secondary hepatic signs (Palmar erythema, spider veins), liver and spleen are enlarged, often develop liver edema, ascites. For chronic viral hepatitis D is undulating, periods of exacerbation alternate with remissions. 15% of patients with Delta hepatitis fast enough, within a half to two years will develop cirrhosis.
Diagnosis of viral hepatitis D
In the acute phase of the disease in the blood marked specific IgM antibodies for several subsequent months are determined only IgG. In General practice the diagnosis is carried out using the PCR method, allowing us to isolate and identify RNA virus.
To study the state of the liver in viral hepatitis D is a liver ultrasound, Medicom, MRI of the liver and biliary tract. In some cases, further diagnosis can be performed puncture biopsy of the liver. Nonspecific diagnostic measures are similar to those in hepatitis different etiologies and is intended for dynamic control of the functional state of the liver.
Treatment of viral hepatitis D
Treatment of hepatitis D is performed by the gastroenterologist on the same principles as the treatment of viral hepatitis B. Since hepatitis D has a more pronounced resistance to interferon, antiviral therapy basic adjust in the direction of increasing dosage and the course duration is 3 months. In the absence of effective dosages are doubled, the rate shall be extended to 12 months. Since the hepatitis D virus has a direct cytopathic effects, the drugs of the group of corticosteroid hormones in this infection is contraindicated.
Prediction and prevention of viral hepatitis D
The forecast in the case of co-infection easy and moderate severity is more favorable, since complete recovery is noted more often than in superinfection. However, the combined incidence of virus hepatitis b and D is often severe with the development of life-threatening complications. The chronic co-infection develops in 1-3% of cases, while superinfection develops into a chronic form in 70-80% of patients. Chronic viral hepatitis D leads to the development of cirrhosis. Recovery in the event of superinfection is extremely rare.
Prevention of viral hepatitis D is similar to that in viral hepatitis B. of Particular importance are preventive measures for people suffering from hepatitis b and a positive reaction for the presence of HBsAg antigen. Specific vaccination against hepatitis b effectively protects against Delta hepatitis.