Hepatitis Flashcards
Viral causes of hepatitis
- Hepatitis viruses (A, B, C, D, E)
- EBV + CMV (severe in immunocompromised)
- Yellow fever (flavivirus, transmitted by mosquitos)
Bacterial causes of hepatitis
- Leptospirosis
- Brucella
- Coxiella (Q fever)
- Mycobacteria
Parasite causes of hepatitis
- Schistosoma
- Hydatids
- Fluke
Stages of acute hepatitis
INCUBATION: 2 - 9 weeks depending on pathogen
PRE-ICTERIC/PRODROME - malaise, anorexia, nausea, fever
ICTERIC - jaundice, dark urine, pale stools, RUQ pain, may be hepatomegaly, splenomegaly, lymphadenopathy
Hepatitis A: type, transmission, incubation, prevalence
- RNA virus
- Faecal-oral
- Incubation period 2-5 weeks
- Endemic in developing world
- More common in crowded places and areas of poor sanitation
- UK 30% seropositive (70% susceptible)
- Outbreaks from food, water and sometimes contaminated blood products
Hepatitis A presentation
- Acute hepatitis - no chronic/carrier state
- Patients may be asymptomatic (esp <5yo)
- Fulminant hepatitis rare (0.01%), more common in older adults or those with existing chronic liver disease
Hepatitis A investigations
BLOODS
• Liver enzymes (ALT, AST) dramatically raises (>1000)
• bilirubin may be raised
• prolonged INR rare and suggests hepatic necrosis
SEROLOGY
• IgM acute infection, IgG immune
• Viral hep screen to exclude acute hepatitis B or C infection
OTHER
• Liver US usually normal
• Biopsy only in cases of diagnostic uncertainty
Hepatitis A serology
http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/hepatology/hepatitis-A/images/hep-a-figure-1.jpg
Hepatitis A management
- Usually self limiting
- Supportive, advise to avoid paracetamol and alcohol
- Fulminant liver failure needs specialist liver unit care and may require transplant
- Notify HPA
- Consider vaccination of contacts in outbreaks
- Immunoglobulin can give immediate passive immunity lasting up to 3 months
Hepatitis A vaccination info
- Purified, inactivated Hep A
- Creates active immunity, give at least 2 weeks, preferably a month before travel/exposure
- Repeat at 6-12 months
Indications for hep A vaccine
- Travel to intermediate or high prevalence of Hep A
- MSM
- Haemophiliacs or people who will receive blood products
- IVDUs
- Occupational hazards (sewers, primates)
Hepatitis E: type, transmission, incubation, prevalence
- Faecal-oral
- Usually waterborne, also food
- Hosts include pigs, monkeys, rodents and sheep
- Incubation 2 - 9 weeks
- Less prevalent and less easily spread than A
- Endemic in Central and South East Asia, North and West Africa and the Middle East
- No vaccine
Hepatitis E: presentation and control
- Acute, may be asymptomatic or fulminant
* Ensure good sanitation, make sure pork properly cooked
Hepatitis B: type, transmission, incubation, prevalence
- DNA virus, uses host hepatocytes for replication
- Transmission: Perinatal (most common worldwide); IVDU, sexual contact, infected blood products, needlestick
- Incubation period 6 weeks to 6 months
- Most common serious liver infection world-wide
- Worldwide 400 million people have; >500 000 deaths/year
Hepatitis B: illness
- Can be acute or chronic
* 5-10% become chronic, in children who acquire through vertical transmission, up to 80%