Hepatitis viruses are a group of pathogens that primarily invade the liver and cause viral hepatitis, some of which can also cause brain, lung, and heart damage.
Principle
There are currently five recognized human hepatitis viruses, including hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV), which belong to different viral families and genera. Hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV) belong to different virus families and genera. According to the transmission route and pathogenic characteristics, they can be divided into two categories: one category is mainly transmitted by fecal-oral route, including HAV and HEV, which cause acute hepatitis and do not develop into chronic hepatitis or chronic carriers; the other category is mainly transmitted through blood exposure and sexual route, including HBV, HCV and HDV, which can cause acute hepatitis, but also can develop into cirrhosis or even hepatocellular carcinoma chronically. The biological characteristics of these hepatitis viruses are different, and the diseases caused by them are somewhat similar.
Operation method
Clinical manifestations and specimen collection of hepatitis viruses
Principle
(i) Acute hepatitis is divided into acute jaundice hepatitis and acute non-celiac hepatitis, with an incubation period of 15~60 days and a total duration of 2~4 months. Clinical symptoms of non-celiac hepatitis are generally milder than those of the acanthamoeba type. The clinical course of typical acute acanthamoeba hepatitis is generally divided into three phases: 1. Pre-jaundice, which lasts for an average of 5 to 7 days. There are chills, fever and malaise. Lack of appetite, nausea, anorexia of oil. Abdominal discomfort, pain in the liver area, gradual deepening of urine color and other symptoms. 2. Jaundice period usually lasts for 2~6 weeks. The fever subsides, yellowing of sclera and skin appears, jaundice appears with improvement of conscious symptoms, hepatomegaly with tenderness and pain on percussion, and mild splenomegaly in some patients.3. Recovery period This period lasts from 6 weeks to 4 months, with an average of 1 month. Conscious symptoms will be reduced to disappear, jaundice will gradually subside, liver and spleen will gradually return to normal, and liver function will gradually recover. (II) Chronic hepatitis can be diagnosed as chronic hepatitis if there is history of HBV, HCV, HDV infection and hepatitis symptoms, signs and liver function abnormalities, or the duration of acute hepatitis is more than 6 months. Common symptoms are fatigue, general malaise, loss of appetite, discomfort or pain in the liver area, abdominal distension, low-grade fever, and physical signs of dark color. Sclera yellow staining, may have spider nevus or liver palm, hepatomegaly, medium texture or fullness, percussion pain, splenomegaly in severe cases may have deepening of jaundice ﹑ abdominal effusion, lower limb edema, hemorrhagic tendency and other symptoms and hepatic encephalopathy. According to the degree of liver damage, chronic hepatitis is classified as mild, moderate and severe.1. Mild disease, symptoms are not obvious or although there are symptoms and signs, but the biochemical indexes are only 1~2 items of mild abnormality.2. Moderate symptoms and signs reside in the middle between mild and severe, biochemical indexes have mild to moderate abnormality, albumin is 32~35 g/L.3. Severe hepatitis has obvious or persistent symptoms, such as tiredness, lack of appetite, abdominal distension, Lack of appetite Abdominal distension. Stool, etc., accompanied by liver disease face, liver palm, spider nevus or hepatosplenomegaly, excluding other causes and without portal hypertension. Laboratory tests should include repeated or persistent elevation of serum alanine aminotransferase (ALT), decreased albumin or abnormal albumin/globulin (A/C) ratio, and markedly elevated gammaglobulin. Where albumin ≤ 32 g/L, bilirubin > 85.5 pumolL, and prothrombin activity is reduced to between 40% and 60%, any one of these three tests, combined with the above symptoms and signs, can be diagnosed as severe chronic hepatitis. (III) Severe hepatitis 1. Acute severe hepatitis has rapid onset, rapid progression, and deep xanthosis. Neuropsychiatric symptoms appear rapidly within 10 days after the onset of the disease, bleeding tendency is obvious, and liver odor, abdominal effusion, hepatorenal syndrome, plasminogen activity is less than 40%, cholesterol is low, and liver function is obviously abnormal. 2. Subacute severe hepatitis ﹑ after the onset of the disease for 10 days, there are still extreme fatigue, lack of appetite, and severe jaundice (bilirubin >17 pumolL). Abdominal distension and abdominal fluid formation, mostly obvious bleeding phenomenon, general liver shrinkage is not prominent, serum ALT is elevated or elevation is not obvious, and total bilirubin is obviously elevated, i.e., bilirubin enzyme is separated, the ratio of A/C is inverted, the gammaglobulin is elevated, the prolongation of the prothrombinogen time, prothrombinogen activity is lower than 40%, and hepatic encephalopathy is often seen in the late stage of severe impairment of liver function. 3. Chronic hepatitis ﹑ there are chronic hepatitis, cirrhosis or HBV surface disease, and the liver function is severely impaired. Cirrhosis or HBV surface antigen carrier history, imaging, laparoscopy or liver puncture to support chronic hepatitis manifestations, and the clinical manifestations of subacute severe hepatitis and laboratory findings suggestive of chronic severe hepatitis. (D) Biliary hepatitis HAV, HBV, HEV infection can be manifested as biliary hepatitis, which mostly occurs several weeks after the onset of acute hepatitis. Silt-type hepatitis is characterized by mild clinical symptoms, which are not parallel to the degree of jaundice. The onset of the disease is similar to acute jaundice hepatitis, but the conscious symptoms are often milder, with obvious hepatomegaly, itchy skin, light stool color, serum alkaline phosphatase, y-transpeptidase, cholesterol are significantly increased, jaundice is deep, bilirubin is elevated and direct bilirubin is mainly increased, transaminases rise is small, prothrombin time and thromboplastin activity is normal. (E) Cirrhosis after hepatitis HBV, HCV, HDV infection can cause cirrhosis. Early cirrhosis must rely on pathologic diagnosis, ultrasound and CT examination, etc. Laparoscopy is the most valuable reference. Clinically, patients with chronic hepatitis have manifestations of portal hypertension, such as varicose veins in the abdominal wall and esophagus, fluid accumulation in the abdominal cavity, shrinkage of the liver, splenomegaly, widening of the inner diameter of the portal vein and the splenic vein, and exclude other causes that can cause portal hypertension, then the diagnosis of cirrhosis is made, and it is classified into active cirrhosis and quiescent cirrhosis according to the degree of the activity of hepatitis.
Materials and Instruments
Materials: blood, liver tissue, feces. Move Specimens used for hepatitis virus testing include blood, liver tissue. Feces and various body fluids that may contain the virus. Blood specimens are used for the detection of antigenic and antibody markers and nucleic acids in the serum of all types of hepatitis viruses. Venous blood is collected aseptically in a dry test tube, the serum is separated and placed at -4 ℃, and the test is completed within 24 hours. Fecal specimens were used for the detection of viral particles in HAV and HEV infected patients. For testing, 20 g of feces is collected in a collection bottle or plastic bag and either refrigerated for testing or stored at -20 ℃ for testing. Liver biopsies and autopsy specimens are used for virus isolation and nucleic acid or antigen detection. The tissue should be collected in a sterile glass bottle with a lid, and the autopsy specimen should be collected as early as possible within 24 hours after the death, and the specimen used for virus isolation should be taken within 3~6 hours after the death. Saliva specimens should be used for virus isolation or antigen and nucleic acid detection. In the early morning, after rinsing with water and resting for 10 minutes, 5ml of saliva should be collected in a sterile test tube. Milk specimen is used for virus isolation or antigen and nucleic acid testing of HBV and HCV. 2~4 days after delivery, after washing the nipple with sterile 0.9% NaCl solution, 5~10 ml of breast milk was retained in a sterilized vessel or wide-mouth vial. semen was used for viral isolation or antigen and nucleic acid testing, and was collected with a clean condom. Pharyngeal swabs are used for fecal-oral hepatitis virus isolation or nucleic acid testing, and the collection method is the same as that in Chapter 6, Respiratory viruses. Testing for HAV and HEV in the environment is usually performed by collecting samples of potentially contaminated seafood (HAV) and sewage (HEV) for detection of hepatitis virus nucleic acids. Caveat 1. Sampling time, serological testing usually uses serum or plasma collected and separated within 24 hours, if the test cannot be performed within 24 hours, the sample can be stored at 2-8 ℃ for 5 days, or placed in -70 ℃ for long-term freezing, which can keep the antibody titer stable. Fecal specimens should be collected at the peak of detoxification (end of latent phase, early acute phase, and pre-jaundice), and double sera should be collected in the acute phase and the recovery phase (2-4 weeks or more after the onset of the disease) for the detection of specific IgG. 2. Collection Requirements Because heparin interferes with serologic test results, heparin-free, non-anticoagulant tubes must be used to collect serologic samples. Blood samples for nucleic acid testing (viral nucleic acid levels, genotyping, drug resistance testing) should be collected in tubes containing EDTA (purple cap) or dextrose citrate (yellow cap) and should be completed within 6 hours. Repeated freezing and thawing of serum samples after collection should be avoided as this may result in a decrease in antibody titer. Note that vaginal secretion specimens should not be collected during menstruation or when the vaginal mucosa is damaged to avoid blood contamination; all specimens should be stored at -20 ℃. 3. Packaging and transportation of specimens should be kept as cold as possible during transportation. For more product details, please visit Aladdin Scientific website.