viral hepatitis Flashcards
(37 cards)
what is hepatitis
inflammation of the liver
acute vs chronic hep
acute less than 6 monts
chronic more than 6 months
symptoms of acute hepatitis
None or non-specific, e.g. malaise, lethargy, myalgia
Gastrointestinal upset, abdominal pain
Jaundice + pale stools / dark urine
signs of acute hep
Tender hepatomegaly ± jaundice
± signs of fulminant hepatitis (acute liver failure), e.g. bleeding, ascites, encephalopathy
bloods for acute hep would show
Raised transaminases (ALT/AST»_space; GGT/ALP) ± raised bilirubin
infectious causes of acute hep can be split into
viral
non viral
viral causes of acute hep
Hepatitis A, B ± D, C & E
Human herpes viruses, e.g. HSV, VZV, CMV, EBV
Other, e.g. influenza, SARS-CoV-2
non viral causes of acute hep
Spirochaetes, e.g. leptospirosis, syphilis
Mycobacteria, e.g. M. tuberculosis
Bacteria, e.g. bartonella
Parasites, e.g. toxoplasma
non infectious causes of acute hep
Drugs
Alcohol
Other toxins / poisoning
Non-alcoholic fatty liver disease
Pregnancy
Autoimmune hepatitis
Hereditary metabolic causes
patients with chronic hep may have signs of …
liver disease
clubbing, palmar erythema, Dupuytren’s contracture, spider naevi, et
compensatory mechanism of chronic hep
liver function maintained
decompensated mechanism of chronic hep
coagulopathy (↑PT, INR)
jaundice (↑bilirubin)
low albumin
ascites (± bacterial peritonitis)
encephalopathy
infectious causes of chronic hep
Hepatitis B ± D, C (& E)
non infectious causes
Drugs
Alcohol
Other toxins / poisoning
Non-alcoholic fatty liver disease
Autoimmune hepatitis
Hereditary metabolic causes
link between hep b and d
a patient needs hep b to have hep d
What is Hep A?
The Hepatitis A virus is a non-enveloped single-stranded RNA virus.
Acute only
Hep a is spread through?
contaminated food and water
RFs for Hep A
- Travel: those travelling to endemic areas
- Sexual:**high risk activities (e.g analingus, digital-rectal contact, chemsex), multiple partners
- Haematological disorders: factor VIII and factor IX concentrates have been implicated in transmission
- Occupational risks: for example laboratory or sewage workers
- IV drug users:**known to be at increased risk
Pathophysiology of Hep A
- Hep A is a picornavirus
- Replicates in the liver, is excreted in bile then excreted in the faeces for about 2 weeks before the onset of clinical illness and for up to 7 days after
- infectious JUST BEFORE the onset of jaundice
- Short incubation period of 2-6 weeks
- Causes ACUTE HEPATITIS ONLY
- 100% immunity after infection
Phases of Hep A
Hepatitis A is said to follow four clinical phases (though significant variation exists).
- Incubation:**Hepatitis A has a relatively long incubation period that may last from 2 - 6 weeks (mean 28-30 days).
- Prodromal: Early part of the disease, characterised by fever, joint pain and rash. Flu-like symptoms may be present
- Icteric:**In addition to jaundice, the icteric phase is characterised by anorexia, abdominal pain and change in bowel habit.
- Convalescent:**Recovery phase as the body returns to normal and symptoms subside. Symptoms like malaise may last months.
presentation of Hep a
non specific symptoms
RUQ tenderness
jaundice
Hepatomegaly
Nausea
what would you see in antibody test (serology) for HeP A (GS 1st line investigation)
- +ve HAV-IgM, +ve HAV-IgG:**Likely acute hepatitis A infection
- +ve HAV-IgM, -ve HAV-IgG:**May indicate acute infection or false positive IgM
- -ve HAV-IgM, +ve HAV-IgG:**Indicates previous infection or vaccine based immunity
- -ve HAV-IgM, -ve HAV-IgG:**No evidence of infection, may be very early or still in the incubation phase
Hep A management
supportive
monitor liver function
vaccine
Complications of Hep A
- Relapsing hepatitis(may occur in 5-15%)
- Fulminant liver failure
- Prolonged cholestasis
- Others(interstitial nephritis, acute pancreatitis, red cell aplasia, Guillian-Barre syndrome)
