By the way... does anyone else think Bart Simpson might be jaundiced?!?
A week after admission the results from the reference laboratory confirmed that he had Hepatitis E. The response from the ward doctors was “I’ve heard of A, B and C but what the heck is E?!”
So what is Hepatitis E?
Hepatitis E (Hep E) is a viral hepatitis transmitted by the faecal-oral route; the main source is contaminated water although food can very occasionally be implicated. There are 4 main genotypes (1-4) that infect humans whilst types 3 and 4 can also infect animals.
Hep E occurs predominantly in Asia, Africa, the Middle East and Central America, especially in areas where there is poor management of human waste. Outbreaks can be vast and occur over prolonged periods of time; the largest reported outbreak was of over 100,000 people infected in China from 1986 to 1988. Most cases diagnosed in the UK have been acquired abroad.
The incubation period of Hep E is very variable ranging from 15-64 days. The virus can persist in faeces and patients remain infectious from 1 week before symptoms occur to 2 weeks after they become jaundiced although person-to-person transmission is uncommon without food or water contamination. Strict attention to enteric precautions is essential to prevent further cases.
Hep E causes an acute hepatitis which is normally self-limiting although it is estimated that 50% of cases are asymptomatic. Fulminant hepatitis causing liver failure is rare (<0.5%) in healthy adults, except in pregnancy where for unknown reasons fulminant hepatitis occurs frequently with an overall mortality of 15-25%! Chronic Hep E is very rare and only occurs in immunocompromised patients or those who have had a liver transplant who are unable to clear the virus themselves.
The clinical features are those of hepatitis:
- Abdominal pain
Blood tests show a raised bilirubin, Aspartate Transaminase (AST) and Alanine Transaminase (ALT) indicating liver cell damage, and these can take up to 6 weeks to return to normal.
How is Hepatitis E diagnosed?
Hep E is diagnosed by detecting Hep E IgM in serum or the virus itself in serum or stool by PCR. The serum antibody test can have both false negative and false positive results but for patients in the UK with a typical clinical presentation and history of travel it is pretty reliable for making the diagnosis.
The differential diagnosis of Hepatitis E includes other infections, and these should also be considered whilst investigating for Hep E, especially leptospirosis, malaria and enteric fever which are all emergencies for which urgent antimicrobial therapy is indicated:
- Hepatitis A, B and C
- Epstein-Barr virus (EBV)
- Cytomegalovirus (CMV)
- Leptospirosis (Weil’s Disease)
- Enteric fever (Typhoid and Paratyphoid)
How is Hepatitis E treated?
Unfortunately there is no specific treatment for Hep E. Supportive care should be given and blood tests should be monitored to ensure that the liver recovers.
So with the diagnosis confirmed as Hepatitis E all of the patient’s antibiotics were stopped. Enteric precautions were kept in place; a side-room with toilet facilities, strict hand hygiene, gloves and aprons. After two weeks he felt well enough to go home and his liver function tests slowly returned to normal. He eventually made a full recovery but on leaving the hospital he remarked that his trip of a lifetime had become memorable for other reasons than just visiting the jungle!