What is the typical course of a hepatitis E infection?
In Germany, the disease with the hepatitis E virus often proceeds with few or no symptoms. If symptoms occur, they are usually mild and spontaneous healing occurs. The symptoms can affect the gastrointestinal tract and cause discoloration of the stool, darkening of the urine, nausea, vomiting and diarrhea.
In contrast to the other liver inflammations, jaundice (icterus) rarely occurs. In rare cases, however, a severe infection with severe symptoms and pronounced inflammation of the liver can occur. This is particularly the case if the person affected already has a liver disease.
In addition to the typical symptoms of hepatitis, neurological involvement such as meningitis can also occur. Although hepatitis E heals in most cases, in immunocompromised patients it can also become chronic (permanent) and in rare cases lead to liver failure. But even with a weakened immune system, symptoms often do not develop.
Duration of the disease
The course of symptomatic hepatitis E can be divided into different stages: The prodromal stage with symptoms such as fever, fatigue and pressure pain in the right upper abdomen lasts up to one week. The following second stage with jaundice lasts up to eight weeks.Normally, however, there is an improvement in liver values after only 14 days. In rare cases the course can be severe and in immunocompromised patients it can lead to a permanent infection. Hepatitis E should be avoided at all costs, especially in pregnant women, as the risk of severe courses is increased and mortality during pregnancy is also more likely.
Diagnostics
Hepatitis E is diagnosed on the basis of a medical, clinical examination and detection of antibodies (anti-HEV IgM and anti-HEV IgG) in the blood. It is also possible to detect the virus in the stool or in the liquid part of the blood (serum) by direct detection of hepatitis E RNA (ribonucleic acid), i.e. part of the human genome, using a so-called “polymerase chain reaction” (PCR). In this process, certain sections (sequences) of the DNA are amplified in an enzyme-dependent manner and thus enable the detection of a hepatitis E infection.
If an isolated increase in anti-HEV IgM occurs without an increase in anti-HEV IgG levels, the presence of HEV RNA is evidence of an acute hepatitis E infection. An increase in anti-HEV IgG levels (without an increase in anti-HEV IgM) indicates that the infection is already over, and anti-HEV IgG levels can be used to detect hepatitis E infection years after infection. If symptoms and liver enzyme elevation are indicative of hepatitis E, this must be proven by detection of anti-HEV IgM.
Normally, these antibodies are measurable even when early symptoms appear and can remain detectable for three to six months. If no symptoms are present but hepatitis E is suspected, the pathogen should be detected directly from the blood or stool, e.g. by PCR. The detection of HEV RNA from a stool or blood sample is evidence of a fresh HEV infection.
Also the later antibodies Anti-HEV IgG often test positive at the onset of symptoms, but can remain positive even after the infection has expired and healed. In immunocompromised persons, specific antibodies in the blood are usually detectable only later. Therefore, a nucleic acid amplification technique (NAT) such as PCR should always be used for direct virus detection.
Immunocompromised persons are at increased risk of a persistent hepatitis E infection. On the one hand, liver involvement leads to a significant increase in the so-called transaminases, which can indicate liver cell destruction if elevated in serum. The transferases ALT (alanine aminotransferase) and AST (aspartate aminotransferase) are measured, whereby the quotient of AST and ALT can provide information about the severity of liver cell destruction (de ritis quotient). In severe cases, this quotient is above 1. In the case of liver damage, the synthesis of, for example, albumin and coagulation factors can also be reduced and predict acute liver failure.