Acute Viral Hepatitis Flashcards
What is acute Viral hepatitis?
Acute viral hepatitis (AVH) is a systemic infection predominantly affecting the liver
What are the main viral causes of acute hepatitis?
It is most often caused by viruses that are hepato tropic (hepatitis A, B, C, D, and E)
Other viral infections may also occasionally affect the liver, such as cytomegalovirus (CMV), EBV, herpes simplex, coxsackie virus, and adenovirus
Which are the self-limiting and which are the chronic hepatitis infections?
A + E = self-limiting
B + C usually become chronic
What is the clinical manifestation of acute viral hepatitis?
Whereas most acute infections are asymptomatic, when symptoms are present they appear to be similar for all five types of virus.
It is important to establish which virus is involved, as the risks of progression differ
What is the clinical progression of Hep A infection?
Hepatitis A: self-limiting. The rate of fulminant hepatic failure (FHF) is very low; there is a 1% fatality rate in those over the age of 40
What is the clinical progression of Hep B infection?
Hepatitis B: self-limiting in 80% of cases (adults only), but not in children under the age of 5
What is the clinical progression of Hep C infection?
Hepatitis C: self-limiting in 30% of cases
What is the clinical progression of Hep D infection?
Hepatitis D: self-limiting if HBV is self-limiting
What is the clinical progression of Hep E infection?
Hepatitis E: self-limiting. The overall mortality rate in FHF is 1–3%; in pregnant women the rate is 15–25%
What is teh best indicator for hepatic injury?
A raised serum ALT level is the best indicator of acute hepatic injury, but does not reflect the severity of the disease; values for bilirubin and international normalized ratios (INR) are required for this
When is acute viral hepatitis sinister?
The onset of drowsiness and/or coagulopathy in a patient with acute viral hepatitis is always sinister
What is the viral classification of the hepatitis A virus?
Hepatitis A virus (HAV) is an RNA-containing virus of the Picornaviridae family
7 genotypes of the virus are known, but only 5 of them are pathogenic for the human
The virus contains only one antigen
The virus is highly steady in the environment
What is teh main cause of Hep A transmission?
Most of these occur in areas with poor hygiene and a poor sanitation infrastructure
Infection occurs predominantly in childhood
HAV is usually spread between individuals by oral contact with something that has been contaminated by fecal matter from an HAV-infected person — HAV transmission is fecal–oral
Most transmission is through contact with a household member, tourist travel to an endemic area, contact with a sex partner who has HAV, from an infection in an individual preparing food, or contact with babies in nurseries
Poor hygiene and poor sanitation pose the greatest risks
Who are at risk for HAV?
Children living in poor sanitation and in areas with low hygiene
Children living in areas with a high incidence of HAV
Those participating in anal sex
Users of injected illegal drugs (homeless)
Poor sanitation
Consumers of high-risk foods (e.g., raw shellfish)
Day-care employees and family of children in day care
People traveling to endemic areas
What is the pathological mechanism of HAV?
- Virus enters body through digestive tract
- Virus replicates in the enterocytes
- Virus goes to lymph nodes
- Spreads into bloodstream = viremia
- gets to liver - causes inflammation
