Hepatitis A is an acute infectious liver lesion characterized by a benign course, accompanied by necrosis of hepatocytes. Viral hepatitis A is included in the group of intestinal infections because it has a fecal-oral mechanism of infection. In the clinical course of viral hepatitis A, there are pre-jaundice and jaundice periods, as well as convalescence. Diagnosis is carried out according to biochemical blood analysis, RIA and ELISA results. Hospitalization of patients with viral hepatitis A is necessary only in severe cases. Outpatient treatment includes diet and symptomatic therapy.
Hepatitis A virus belongs to the genus Hepatovirus, its genome is represented by RNA. The virus is quite stable in the environment, persists for several months at 4 ° C and for years at -20 ° C. At room temperature, it remains viable for several weeks, dies when boiled after 5 minutes. Ultraviolet rays inactivate the virus in one minute. The pathogen may remain viable for some time in chlorinated water from a water pipe.
Hepatitis A is transmitted via the fecal-oral mechanism mainly by water and alimentary route. In some cases, it is possible to become infected by contact with household items when using household items, dishes. Outbreaks of viral hepatitis A during the implementation of the infection waterway usually occur when the virus enters public water reservoirs, the food route of infection is possible both when eating contaminated vegetables and fruits, and raw shellfish living in infected reservoirs. The implementation of the contact and household path is typical for children’s groups, where insufficient attention is paid to the sanitary and hygienic regime.
Natural susceptibility to hepatitis A virus in humans is high, the greatest is in pre–puberty children, post-infectious immunity is tense (somewhat less tension is characteristic after a subclinically occurring infection) and prolonged. Infection with viral hepatitis A most often occurs in children’s groups. Among adults, the risk group includes employees of food units of preschool and school kindergartens, as well as medical and preventive and sanatorium-resort institutions, food processing plants. Currently, collective outbreaks of infection among drug addicts and homosexuals are increasingly noted.
Hepatitis a symptoms
The incubation period of viral hepatitis A is 3-4 weeks, the onset of the disease is usually acute, the course is characterized by a sequential change of periods: pre-jaundice, jaundice and convalescence. The pre-jaundice (prodromal) period occurs in various clinical variants: febrile, dyspeptic, asthenovegetative.
The febrile (flu-like) variant of the course is characterized by a sharply developed fever and intoxication symptoms (the severity of the general intoxication syndrome depends on the severity of the course). Patients complain of general weakness, myalgia, headache, dry coughing, sore throat, rhinitis. Catarrhal signs are moderate, redness of the throat is usually not noted, their combination with dyspepsia (nausea, loss of appetite, belching) is possible.
The dyspeptic variant of the course is not accompanied by catarrhal symptoms, intoxication is expressed little. Patients complain mainly of digestive disorders, nausea, vomiting, bitterness in the mouth, belching. Often there is a dull moderate pain in the right hypochondrium, epigastrium. Possible defecation disorder (diarrhea, constipation, their alternation).
The pre-jaundice period, which proceeds according to the asthenovegetative variant, is not very specific. Patients are sluggish, apathetic, complain of general weakness, suffer from sleep disorders. In some cases, prodromal signs are not noted (a latent variant of the pre-jaundice period), the disease begins immediately with jaundice. If there are signs of several clinical syndromes, they speak of a mixed version of the course of the pre-jaundice period. The duration of this phase of infection can be from two to ten days, on average, the prodromal period usually takes a week, gradually moving into the next phase – jaundice.
In the jaundice period of viral hepatitis A, the disappearance of signs of intoxication, a decrease in fever, and an improvement in the general condition of patients are characteristic. However, dyspeptic symptoms, as a rule, persist and worsen. Jaundice develops gradually. First, the darkening of urine is noted, the sclera, the mucous membranes of the frenulum of the tongue and the soft palate acquire a yellowish hue. In the future, the skin turns yellow, acquiring an intense saffron shade (hepatic jaundice). The severity of the disease may correlate with the intensity of skin staining, but it is preferable to focus on dyspeptic and intoxication symptoms.
In severe hepatitis, there may be signs of hemorrhagic syndrome (petechiae, hemorrhages on the mucous membranes and skin, nosebleeds). During physical examination, a yellowish plaque on the tongue and teeth is noted. The liver is enlarged, moderately painful on palpation, in a third of cases there is an increase in the spleen. The pulse is somewhat reduced (bradycardia), blood pressure is lowered. Feces lighten up to complete discoloration at the height of the disease. In addition to dyspeptic disorders, patients may complain of asthenovegetative symptoms.
The duration of the jaundice period usually does not exceed a month, on average it is 2 weeks., after which the period of convalescence begins: there is a gradual regression of clinical and laboratory signs of jaundice, intoxication, the size of the liver normalizes. This phase can be quite long, the duration of the convalescence period usually reaches 3-6 months. The course of viral hepatitis A is predominantly mild or moderate, but in rare cases severe forms of the disease are noted. Chronization of the process and virus transmission are not typical for this infection.
Viral hepatitis A is usually not prone to exacerbations. In rare cases, infection can provoke inflammatory processes in the biliary system (cholangitis, cholecystitis, biliary dyskinesia and gallbladder). Sometimes hepatitis A is complicated by the addition of a secondary infection. Severe complications from the liver (acute hepatic encephalopathy) are extremely rare.
In the general blood test, there is a reduced concentration of leukocytes, lymphocytosis, increased ESR. Biochemical analysis shows a sharp increase in the activity of aminotransferases, bilirubinemia (mainly due to bound bilirubin), a reduced albumin content, a low prothrombin index, an increase in sulemic and a decrease in thymolic samples.
Specific diagnostics is carried out on the basis of serological methods (antibodies are detected using ELISA and RIA). In the jaundice period, there is an increase in Ig M, and in the convalescent period – IgG. The most accurate and specific diagnosis is the detection of virus RNA in the blood using PCR. Isolation of the pathogen and virological examination is possible, but due to the complexity of general clinical practice, it is impractical.
Hepatitis a treatment
Botkin’s disease can be treated on an outpatient basis, hospitalization is performed for severe forms, as well as for epidemiological indications. During the period of severe intoxication, patients are prescribed bed rest, diet No. 5 (in the variant for acute hepatitis), vitamin therapy. Fractional nutrition, fatty foods are excluded, products that stimulate the production of bile, dairy and vegetable components of the diet are encouraged.
A complete exclusion of alcohol is necessary. Etiotropic therapy for this disease has not been developed, a set of therapeutic measures is aimed at relieving symptoms and pathogenetic correction. For the purpose of detoxification, copious drinking is prescribed, if necessary, infusion of crystalloid solutions. In order to normalize digestion and maintain intestinal normobiocenosis, lactulose preparations are prescribed. Antispasmodics are used to prevent cholestasis. If necessary, prescribe drugs ursodeoxycholic acid. After clinical recovery, patients are under dispensary observation by a gastroenterologist for another 3-6 months.
In the vast majority of cases, the prognosis is favorable. With complications from the biliary tract, the cure is delayed, but with false therapy, the prognosis does not worsen.
General preventive measures are aimed at ensuring high-quality purification of drinking water sources, control over wastewater discharge, sanitary and hygienic requirements for the regime at public catering enterprises, in the catering units of children’s and medical institutions. Epidemiological control is carried out over the production, storage, transportation of food products, in case of outbreaks of viral hepatitis A in organized groups (both children and adults), appropriate quarantine measures are carried out. Patients are isolated for 2 weeks, their contagiousness disappears after the first week of the jaundice period. Admission to study and work is carried out upon the onset of clinical recovery. Contact persons are monitored for 35 days from the moment of contact. In children’s groups, quarantine is assigned for this time. In the focus of infection, the necessary disinfection measures are carried out.
Vaccination against hepatitis A is recommended for children from the age of 1 year and adults traveling to areas dangerous for viral hepatitis A.