Overview.
Hepatitis dual or multiple infections refer to the fact that the same patient with viral hepatitis can be infected with two or more different types of hepatitis viruses. There are five known types of hepatitis viruses, which are not cross-immune to each other. There is no cross immunity between them, i.e. after infection with one type of hepatitis virus, one can still be infected with other types of hepatitis viruses. According to the time of infection, it can be divided into simultaneous infection (mixed infection) and overlapping infection (subsequent infection).
Etiology
There are about 280 million HBsAg-positive infected people in the world, and China accounts for about 100 million, of which 2/3 are asymptomatic carriers. Due to the high carrier rate of HBV infection, it is easy to have overlapping infection with other hepatitis viruses through different transmission routes.
Symptoms
1. HBV and HAV double infection
(1) Simultaneous infection This type is less common. Because HBV and HAV are first infected, their clinical manifestations and liver function tests are more obvious than the overlapping infections, except for a few patients with prolonged course, most of them behave like acute jaundice hepatitis with good prognosis. The prognosis was good. No worsening of symptoms and liver damage was seen.
(2) Overlapping infection The overlapping infection rate of HBV and HAV in disseminated acute hepatitis is 0～23.4%.In 1988, during the epidemic of hepatitis A in Shanghai, about 10% of chronic carriers of HBsAg had overlapping infection of HAV.In the area with high rate of HBsAg carriers, there is an outbreak of hepatitis A, and overlapping infections of HBV and HAV are also more common. HAV overlap infection of chronic hepatitis B, in hepatitis A, half of the symptoms are worse than before and ALT elevation, especially in chronic active hepatitis performance is more obvious. If the original cirrhosis is infected with HAV on the basis of cirrhosis, the jaundice deepens, the liver function damage worsens, and ascites and hepatic encephalopathy can appear.
2.HBV and HCV double infection
Since both HBV and HCV have high carrier rate, the chance of overlapping infection is also larger, which is 15%～28%.
3. HBV and HDV dual infection
(1) Simultaneous infection of HBV and HDV Simple acute HDV infection is similar to simple acute HBV infection in terms of clinical symptoms and liver function tests, but sometimes bimodal ALT elevation can be seen, which indicates the infection of HBV and HDV respectively, and this kind of acute hepatitis D is at a lower risk of chronic hepatitis than simple acute HBV infection. The course of the disease is mostly self-limiting and the prognosis is good.
(2) Overlapping HBV and HDV infection Most of them show chronic process, mostly insidious type, but the disease progresses quickly, often develops into chronic active hepatitis and cirrhosis.Whether HBV and HDV infection is simultaneous or overlapping infection, severe hepatitis can occur; HDV infection on the basis of HBV infection is one of the reasons for the development of severe hepatitis and cirrhosis.
4. HBV and HEV dual infection
Hepatitis E can be epidemic or endemic all over the world. In areas with a high prevalence of HBV infection, overlapping HBV and HEV infections may lead to the development of severe hepatitis.
5. HBV and HCV, HDV multiple infection
Multiple infections with 3 or more hepatitis viruses are rare. Disease progression and regression are obviously related to the degree of liver lesions prior to the overlapping infection. If asymptomatic HBsAg carriers present with symptoms and abnormal liver function. If the original chronic active hepatitis or cirrhosis, the clinical symptoms are progressively worsened and liver function impairment is obvious, and the outcome is poor.
Examination
1. Relevant pathogenetic indexes should be tested in time.
Due to the high rate of HBV infection in our country, for those with acute hepatitis manifestations, even if there is no history of hepatitis, it cannot be excluded that they have suffered from hepatitis B before or they are asymptomatic HBsAg carriers, so they should be tested for serum anti-HAV IgM and HBV markers at the same time.
2. The effect of dual infection on viral serologic markers
(1) Simultaneous infection Most studies have concluded that hepatitis viruses do not interfere with each other.
(2) After overlapping infections, some HBV replication indexes can be suppressed, showing that HBsAg titer decreases or disappears; HBsAg in liver tissues even disappears; HBsAg level decreases or disappears, and there can be a positive shift of anti-HBs, and the HBV-DNA and DAN-p are negative or temporarily negative, which indicate that HBV replication is suppressed to varying degrees.
Diagnosis
The original chronic HBV infection, the recent emergence of clinical symptoms, liver function abnormalities; or the original chronic active hepatitis, cirrhosis recently deteriorated and poor treatment results, should be considered to overlap with the possibility of infection with other hepatitis viruses, should be carried out in a timely manner for the relevant pathogenetic indicators test. Due to the high rate of HBV infection in China, for those with acute hepatitis manifestations, even if there is no history of hepatitis, it cannot be ruled out that they have previously suffered from hepatitis B or are asymptomatic HBsAg carriers, so they should be tested at the same time for serum anti-HAVIgM and HBV markers to assist in the diagnosis.
Differential diagnosis
Hepatitis dual infection needs to be differentiated from the following diseases:
1. Toxic hepatitis, alcoholic liver disease
History of toxic exposure or history of alcoholism. The patient’s blood is negative for viral markers.
2. Cholecystitis
Patients are mostly obese, abdominal pain is located in the right side under the convergence process, aggravated after eating greasy food or eggs, there is pressure pain in the gallbladder area, aminotransferases are normal or mildly elevated, and there are corresponding changes in ultrasound or CT examination.
3. Fatty liver
Patients are mostly obese adults with elevated blood lipid, ultrasound suggests diffuse intrahepatic lesions, and blood hepatitis virus markers are negative.
Complications
Severe hepatitis, cirrhosis, hepatocellular carcinoma can be complicated.
Treatment
Symptomatic treatment according to the type of infection.
Prognosis
The prognosis of HBV and HAV overlapping infection depends on the severity of the existing liver disease, and most of them have a good prognosis. However, if it develops into severe hepatitis or the original serious liver disease, the condition tends to aggravate, and the prognosis is not good.
When HBV is infected with HCV, the clinical symptoms are more serious than those of simple hepatitis C or hepatitis B, and the course of the disease is easy to be chronic and recurrent, the liver function is abnormal, and it even develops into severe hepatitis, cirrhosis, or hepatocellular carcinoma.