The etiological classification of viral hepatitis is currently recognized as five types of hepatitis viruses: A, B, C, D, and E, which are written as HAV, HBV, HCV, HDV, and HEV respectively. Except for hepatitis B virus, which is a DNA virus, The rest are RNA viruses. Hepatitis A has been reported, but the pathogen has not been successfully isolated so far. In recent years, it has been reported that the relationship between hepatitis G virus and single-stranded DNA TTV, which are flaviviruses, and human hepatitis is still controversial.

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​Clinical manifestations

1. Acute hepatitis

It is divided into acute icteric hepatitis and acute anicteric hepatitis. The incubation period is between 15 and 45 days, with an average of 25 days, and the total disease duration is 2 to 4 months.

(1) Pre-jaundice includes chills, fever, fatigue, loss of appetite, nausea, oiliness, abdominal discomfort, liver pain, and gradually deepening urine color. This period lasts for an average of 5 to 7 days.

(2) Jaundice stage: fever subsides, sclera and skin are jaundiced, jaundice appears but subjective symptoms improve, hepatomegaly accompanied by tenderness and percussion pain, some patients have mild splenomegaly, this stage lasts 2 to 6 weeks.

(3) Recovery period: jaundice gradually subsides, symptoms are relieved or even disappear, the liver and spleen return to normal, and liver function gradually recovers. This period lasts from 2 weeks to 4 months, with an average of 1 month.

​2. Chronic hepatitis

Those who have a history of hepatitis B, C, D or HBsAg carriers or have an acute hepatitis course of more than 6 months, but still have hepatitis symptoms, signs and abnormal liver function, can be diagnosed as chronic hepatitis. Common symptoms include fatigue, general malaise, loss of appetite, discomfort or pain in the liver area, abdominal distension, and low fever. Physical signs include dull complexion, scleral jaundice, spider nevi or liver palms, enlarged liver, medium or full texture, and percussion pain. , Severe splenomegaly may cause deepening jaundice, abdominal effusion, lower limb edema, bleeding tendency and hepatic encephalopathy. According to the degree of liver damage, it can be clinically divided into:

(1) Mild: The condition is mild, the symptoms are not obvious, or although there are symptoms and signs, there are only 1 to 2 mild abnormalities in the biochemical indicators.

(2) Moderate symptoms and signs, between mild and severe. Abnormal changes in liver function.

(3) Severe or persistent symptoms of hepatitis, such as fatigue, anorexia, abdominal distension, loose stools, etc., which may be accompanied by liver disease, liver palms, spider nevi or hepatosplenomegaly, but other causes are excluded and there is no portal hypertension. Symptoms. Laboratory examination of serum showed repeated or sustained increases in alanine aminotransferase: decreased albumin or abnormal A/G ratio, significantly increased gamma globulin, where albumin was ≤32g/L and bilirubin was >85.5μmol/L, prothrombin activity 60% to 40%, and one of the three tests can be diagnosed as severe chronic hepatitis.

3. Severe hepatitis

(1) Acute severe hepatitis has an acute onset, rapid progression, deep jaundice, and a small liver. Within 10 days after the onset of illness, neuropsychiatric symptoms appear rapidly, bleeding tendency is obvious, liver odor, abdominal effusion, hepatorenal syndrome, prothrombin activity lower than 40% and other causes are excluded, low cholesterol and poor liver function. Obviously abnormal.

(2) Subacute severe hepatitis 10 days after the onset of illness, there is still extreme fatigue, anorexia, severe jaundice (bilirubin >171 μmol/L), abdominal distension, and abdominal effusion, often with obvious bleeding, and generally the liver is shrunken. Not prominent, hepatic encephalopathy is more common in later stages of severe liver function damage: serum ALT increases or is not significantly increased, while total bilirubin increases significantly, namely: bile enzyme separation, A/G ratio inversion, increased gamma globulin, The prothrombin time is prolonged and the prothrombin activity is <40%.

(3) Chronic severe hepatitis: Those with chronic hepatitis cirrhosis or a history of carrying hepatitis B surface antigen, imaging, laparoscopy or liver puncture support the manifestations of chronic hepatitis, and the clinical manifestations and laboratory changes of subacute severe hepatitis are: Chronic severe hepatitis.

4. Cholestatic hepatitis

The onset is similar to acute icteric hepatitis, but the subjective symptoms are often mild, with obvious hepatomegaly, itchy skin, light-colored stools, significantly increased serum alkaline phosphatase, γ-transpeptidase, and cholesterol, deep jaundice, and biliary redness. The increase in blood glucose was mainly directly increased, the increase in transaminase was small, and the prothrombin time and prothrombin activity were normal. It is characterized by mild clinical symptoms that are inconsistent with profound jaundice.

5. Post-hepatitis cirrhosis

Early liver cirrhosis must rely on pathological diagnosis, ultrasound and CT examination, among which laparoscopy has the most reference value. Clinical diagnosis of liver cirrhosis refers to patients with chronic hepatitis who have symptoms of portal hypertension, such as abdominal wall and esophageal varices, peritoneal effusion, shrinkage of the liver, splenomegaly, widening of the diameter of the portal vein and splenic vein, and other causes that can cause portal hypertension are excluded. , divided into active and quiescent cirrhosis according to the degree of hepatitis activity.