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%
Complications of chronic hepatitis infection
- Cirrhosis (25%)
- End stage liver disease
- Hepatocellular carcinoma
Stigmata of chronic liver disease
These come from problems with either metabolic or synthetic function
• Jaundice (bilirubin metabolism)
• Bruising (impaired synthesis of vitamin K dependent clotting factors)
• Leukonychia - hypoalbuminaemia
• Portal hypertension:
- Splenomegaly
- Caput medusa
- Ascites
(- Varices and haemorrhoids)
• Hepatic encephalopathy
- flap
- confusion/drowsiness
• Altered oestrogen metabolism
- gyneacomastia
- testicular atrophy
- loss of axillary hair
• Palmer Erythema
• Dupytren's
• ClubbingHepatitis B investigations
BLOODS • LFTs, clotting factors • Hepatitis B core DNA • Liver US • Fibroscan (US that measures 'stiffness' of liver • Liver biopsy
Things to screen for in those with cirrhosis
- Alpha fetoprotein (for HCC)
- Abdominal US
- OGD to assess for varices
Hepatitis B serology
http://www.bio-rad.com/webroot/web/images/cdg/products/blood_virus/product_overlay_content/global/bvd_monolisa_antihbc_01b_overlay.jpg
http://depts.washington.edu/hepstudy/images/hepB/HBV_Serologic_d02.png
HBsAg (antigen) = acute infection with HBV (if present more than 6 months = chronic)
Anti-HBs (antibody) = immunity following infection or vaccine
HBeAg = may be present in acute or chronic, signifies high-infectivity
NEEDS MORE
Advice in Hep B
- Avoid alcohol
* Have Hep A vaccine if not immune
Prevention of Hep B
- Protected sex
- Don’t share razors
- Careful treatment of cuts
- Vaccination of household contacts
- Screening of blood products
- Pre-exposure vaccination in at risk groups (children in endemic areas; healthcare staff; partners of patients)
- Post exposure vaccine/Ig for sexual contacts, needlestick injuries or babies born to infected mothers
Treatment of Hepatitis B
Acute: Supportive
Chronic:
• Inactive HBsAg carriers or normal ALT just monitor
• Deranged LFTs or cirrhosis give antivirals (tenofovir; entecavir; pegylated interferon; [lamivudine])
Patients with decompensated cirrhosis may be eligible for transplant
Hepatitis D
- Requires co-infection with hepatitis B to replicate
- Simultaneous hepatitis B and D infections increase the risk of fulminant hepatitis
- Exacerbations of hepatitis may occur in patients with hepatitis B who acquire hepatitis D
- Common in Southern Italy, North Africa and Middle East
- Check hepatitis D serology in all hepatitis B patients
Hepatitis C: type, transmission, incubation, prevalence
- RNA virus
- Transmitted through blood and sexual contact
- Incubation period 2 weeks to six months
- 170 million people worldwide
- Common in IVDU
- Common in Egypt, Taiwan and Japan
- No vaccine available
Hepatitis C: presentation
- May give acute infection, but usually less severe than hepatitis A or B
- 80% infections become chronic
- Of these, 20% develop cirrhosis
- Of these, 1/3 develop HCC
Hepatitis C investigations
- AST and ALT not as markedly raised as in B or C
- Serology detects antibody to hepatitis C but can’t distinguish if active or passive infection
- Hepatitis C RNA detects virus in blood (shows active infection)
- Viral genotyping to guide treatment (6 genotypes, of which 1a is most difficult to treat)
- Serology for other hepatitis viruses (and vaccinate against A and B if not immune)
- Liver US; alpha fetoprotein; fibroscan; liver biopsy (more accurate, although more invasive assessment of cirrhosis)
Hepatitis C prevention
- Screening of blood products
- Needle exchange programs and education for IVDU
- Universal infection control procedures
Hepatitis C treatment
Supportive for acute infections
CHRONIC
Standard:
• Pegylated Interferon (flu-like, neurological, psychiatric symptoms; bone marrow suppression)
• Ribavirin (in conjunction with interferon; haemolytic anaemia)
New treatments:
• Addition of protease or polymerase inhibitors increase response rate but also side effects
Transplant may be indicated in cirrhosis or end stage liver disease. Transplant or resection may be indicated in HCC.
