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Hepatitis A. Infectious Hepatitis"First characterized in 1973Detected in human fecesHepatovirus genusA reportable infectious diseaseU.S. rate of infection 4/100,000Highest among children. Risk Factors. Sexual or household contactInternational travelMen who have sex w/ men (MSM)Intravenous
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1. Hepatitis A The virus that does not cause chronic liver disease
2. Hepatitis A “Infectious Hepatitis”
First characterized in 1973
Detected in human feces
Hepatovirus genus
A reportable infectious disease
U.S. rate of infection 4/100,000
Highest among children
3. Risk Factors Sexual or household contact
International travel
Men who have sex w/ men (MSM)
Intravenous drug abuse (IVDA)
Daycare
4. Transmission Unwitting contact w/ infected person
Most cases unknown
Primary route is fecal oral either by person to person contact or ingestion of contaminated food or water
5. Pathogenesis After ingestion, the HAV survives gastric acid, moves to the small intestine and reaches the liver via the portal vein
Replicates in hepatocyte cytoplasm
Not a cytopathic virus
Immune mediated cell damage more likely
Once mature the HAV travels through sinusoids and enters bile canaliculi, released into the small intestine and systemic circulation, excreted in feces
6. Clinical Features Incubation is usually 2 to 4 weeks, rarely 6 weeks
Complete recovery within 2 months for > 50%
Within 6 months for almost all others
7. Clinical Features Low mortality in healthy people
High mortality when older than age 60
High in presence of chronic liver disease
High morbidity
Around 20% need hospitalization
Lost work days
Most become jaundiced
8. Clinical Features Asymptomatic < 2 year old
Symptomatic – 5 and older ill about 8 weeks
Cholestatic – jaundice lasts > 10 weeks
Relapsing w/ 2 or more bouts acute HAV over a 6 to 10 week period
Acute liver failure – rare in young. When it occurs, is rapid i.e., within 4 weeks
9. Signs and Symptoms Prodrome lasts 1-2 weeks: fatigue, asthenia, anorexia, nausea, vomiting, and abdominal pain
Less common: fever, cephalgia, arthralgia, myalgia, and diarrhea
Dark urine is followed by jaundice and hepatomegaly
Less common: splenomegaly, cervical lymphadenopathy
10. Diagnosis During acute infection, anti HAV IgM appears first
HAV IgG antibody appears early in the course of infection and remains detectable for life, providing lifelong immunity
11. PreventionImmunization All children 12 – 24 months
Travelers, occupational exposure risk
All patients w/ hepatitis B or C or those awaiting liver transplantation
HIV positive patients
MSM
IVD users
12. Immunize People w/ clotting factor deficiencies
Lab workers handling live hepatitis A vaccine
Need for post exposure prophylaxis uncommon. Administration of the vaccine is effective. If needed, administer immune serum globulin within 2 weeks 0.02 ml/Kg IM
13. Hepatitis A Vaccine The vaccine is inactivated HAV
Schedule for 2 – 18 years depends upon the manufacturer:
Havirx: 720 EL U/.5mL @ 0, 6-12 mo
Vaqta: 25 U.5mL @ 0, 6-18 mo
14. Hepatitis A Vaccine For those over age 18:
Havirx: 1440 EL U/1mL @ 0, 6-12 mo
Vaqta: 50 U/1mL @ 0, 6-18 mo
Adverse effects: rarely anaphylaxis, injection site induration, erythema, edema, fatigue, mild fever, malaise, anorexia, nausea
Twinrix:
720 El U/1mL 0, 1, 6 mo plus
20 mcg HBV
15. Questions?
16. Hepatitis B
17. The Virus The hepatitis B virus is among the smallest genomes of all known animal viruses
A DNA virus that infects only humans
Belongs to the family Hepadnaviridae
Knowledge of the viral proteins that are perceived by the immune system as “antigens” aids understanding of the various tests used to diagnose acute, chronic, and resolved infection and verify response to immunization
18. HBV Antigens Outer envelope contains a surface protein called hepatitis B surface antigen
HBsAg is a marker of viral replication
Inner core contains the genome, the DNA polymerase w/ reverse transcriptase activity, hepatitis B core antigen (HBcAg) particles. This antigen is not detectable in serum
A truncated form of the major core polypeptide known as hepatitis e antigen (HBeAg) is the third antigen generated by virus activity. Marker of high infectivity
19. Hepatitis B Antibodies Hepatitis B surface antibody is the antibody to surface antigen. HBsAb is protective and indicates either resolved infection or immunization
HBcAb is the antibody to core antigen. This is not a protective antibody. Only those who have been exposed to the virus will have this antibody
HBcAb is measured in serum as:
Anti HBc IgM (usually indicates new infection)
Anti HBc IgG (appears later)
HBeAb is the antibody to e antigen. Loss of e antigen w/ gain of e antibody is called seroconversion. Not a protective antibody
20. Epidemiology Prevalence of HBV varies markedly around the world, w/ > 75% of cases in Asia and the Western Pacific
Vaccine available > 20 years, but perinatal and early life exposure continue to be a major source of infection in endemic areas
Most acute HBV cases in the U.S. are seen among young adults, males > females, who use injection drugs and in those who engage in high risk sexual behaviors
In the U.S., hundreds of people die each year of fulminant HBV
World wide, chronic HBV and its complications including hepatocellular carcinoma account for > 1 million deaths each year
21. Risk Factors Percutaneous and mucous membrane exposure. The virus is 100 x more infectious than HIV, 10 x more infectious than HCV and is present in all body fluids. Present on horizontal surfaces, eating utensils, personal hygiene items, etc.
Babies born to infected mother
Household contact
Hemodialysis
Receipt of blood products prior to the early 1970s
Receipt of previously infected donor liver
22. Markers of Exposure Surface antigen appears as early as 1-2 weeks following exposure, as late as 11-12 weeks
HBV DNA measurable soon after
HBeAg appears shortly after HBsAg
Hepatitis occurs 1 – 7 weeks after appearance of HBsAg
23. Pathophysiology Governed by interaction between the virus and host immune response
Following inoculation by the HBV, cytokine release, cell injury and viral clearance follow
HBsAg disappears by six months and is accompanied by sero conversion to protective HBsAb
Persistent virus replication after six months ->chronic hepatitis and is the result of a compromised (newborn/HIV) or relatively tolerant immune system status
24. Four Stages of Infection Age at time of infection predicts chronicity in most cases. Infants and young children usually become chronically infected. When acquired in adults, the virus is cleared by the healthy immune system in about 95% of cases, leading to natural immunity
Immune tolerant phase, there is active viral replication. ALT and AST are normal. Immune system does not recognize HBV as “foreign”
In the immune clearance phase, enzymes rise reflecting immune mediated lysis of infected hepatocytes. This phase can last for years. Seroconversion of HBeAg to HBeAb occurs
25. Stages of Infection Low or non-replicative phase. Also known as inactive carrier (or inappropriately “healthy carrier”). Characterized by resolution of necroinflammation, normalization of enzymes and low levels of HBV DNA. This stage may last for life
Reactivation. Spontaneous or immunosuppression mediated (cancer chemotherapy or high dose corticosteroid therapy)
26. Signs and Symptoms Incubation period: a few weeks to 6 months
About 30% develop jaundice
10% to 20% of patients develop serum sickness, i.e., fever, arthralgias, rash
Fulminant hepatitis B occurs in < 1% of cases. 80% mortality without liver transplantation
Enzyme elevations of 1,000-2,000 typical
27. Signs and Symptoms Fatigue, RUQ discomfort may be the only symptoms
Those in the immune tolerant phase are usually asymptomatic. The phase lasts until late puberty into adulthood
28. Signs of Decompensation See section on Cirrhosis and Portal Hypertension
Refer to a liver transplantation center
Patient education for people with chronic liver disease should be reinforced
Refer to “Ten Tips for People w/ Chronic Liver Disease”
29. Prevention Two forms of vaccine now available.
Twinrix – contains both hepatitis A and B vaccines available in an accelerated schedule or standard series
Individual hepatitis B vaccine
Standard schedule is given:
Time 0
1 mo
6 mo
30. Prevention Educate to avoid IVDU, high risk sexual activity
Prevent peri natal transmission. Serology of pregnant women for HBsAg is standard of practice in U.S.
If pregnant female has high viremia, refer to hepatologist for treatment during the 3rd trimester to reduce risk of transmission to neonate
Babies of HBsAg mothers receive hepatitis B immune globulin with 12 hours of birth and begin the vaccine series immediately
31. Treatment Six approved medications as of July 2008
Interferon alpha
Pegylated interferon
Lamivudine
Adefovir Dipivoxil
Entecavir
Telbivudine
Tenofovir approved
Refer to hepatologist
32. The Cholestatic Liver Diseases Adults
33. Cholestatic Liver DiseaseEtiologies Immune Mediated: PBC, PSC, autoimmune cholangitis, liver allograft rejection, graft-versus-host disease
Infectious: acute viral hepatitis
Genetic and Developmental: cystic fibrosis, Alagille’s syndrome (syndrome w/ paucity of intrahepatic bile ducts), fibro polycystic liver disease
34. Cholestatic Liver DiseaseEtiologies Neoplastic: Cholangiocarcinoma
Drug-Induced Ductopenia: amoxicillin, amitriptyline, cyproheptadine, erythromycin, tetracycline, thiabendazole
Ischemic
Idiopathic
35. Pathogenesis of Cholestatic Disorders Immune response (inflammation, auto-antibody) or hepatotoxic injury to bile ducts
Bile duct injury by bile acids - >
Retention of bile acids in hepatocytes - >
Liver cell damage, apoptosis, necrosis, fibrosis, cirrhosis - > liver failure
36. Disorganized bile duct architecture as it is destroyed by inflammatory cellsDisorganized bile duct architecture as it is destroyed by inflammatory cells
37. Half of the duct is destroyedHalf of the duct is destroyed
38. Complications of Chronic Cholestasis Pruritis believed to be 2/2 increased opioid receptor tone, or centrally mediated
Fatigue
Bone disease: osteopenia, osteoporosis
Fat soluble vitamin deficiency
Malabsorption (Sprue, bile salt deficiency, pancreatic insufficiency)
39. Pruritis in Cholestasis Therapy:
Urso in AICP, PBC (15-30mg/Kg/day)
Opiate antagonist naltrexone (50mg/day)
5-HT3 antagonist odansetron
SSRI sertaline
Bile acid sequesterant cholestyramine 4gm t.i.d. to q.i.d.
Antihistamines rarely effective
Rifampin 150mg to 300mg b.i.d. AICP: acute intrahepatic cholestasis of pregnancyAICP: acute intrahepatic cholestasis of pregnancy
40. Fatigue in Cholestasis High prevalence in Primary Biliary Cirrhosis unrelated to disease severity or duration
Pathogenesis
?decreased hypothalamic cortico-tropin-releasing hormone
?CNS accumulation of manganese
Prognosis worse
No effective treatment
41. Bone Disease in Cholestasis Clinical manifestations: low bone density, fractures of axial and/or appendicular skeleton
Pathogenesis: hyperbilirubinemia impairs osteoblast proliferative activity
Therapy: bisphosphonates, calcium, vitamin D, weight bearing exercise, estrogens appear to be safe
42. 1. Primary Biliary CirrhosisA chronic and progressive disease of unknown etiology affecting primarily middle-aged women
43. Primary Biliary Cirrhosis Affects all races
9:1 ratio female > male, age 20 – 65
Characterized by small intrahepatic bile duct destruction and cholestasis
In the presence of cirrhosis, male > likely than female to develop hepatocellular carcinoma
44. PBCLaboratory Findings Alk Phos 2x to 20x ULN in > 90% of patients
AST-ALT 1x to 5x ULN > 90%
Bilirubin – variable. When elevated, may indicate advanced cirrhosis or 2nd condition
Hypercholesterolemia in 80% of patients
45. Hypercholesterolemia Unique in PBC Hypercholesterolemia
No obvious increase in heart disease
Some lipid lowering agents cause rise
Cholestyramine or Urso may mobilize cholesterol deposits
46. PBCLaboratory Findings IgM 1x to 5x ULN > 90%
Anti mitochondrial antibody > 1:20 titer >90%
Anti nuclear and/or smooth muscle antibody > 1:80 may be seen in “overlap syndrome”
Liver biopsy helpful to grade and stage disease, determine if cirrhosis present
47. PBC Treatment Slowly progressive, even if asymptomatic
Ursodeoxycholic acid only effective therapy. May improve natural history
Transplant curative
Manage disease specific complications
48. Effects of Ursodeoxycholate Urso is a hydrophilic bile acid having multiple anti-inflammatory and immunomodulatory actions
Urso administration in the setting of pro-apoptotic stimuli (bile salts, ethanol, TGF-beta, FAS ligand) inhibits in vitro apoptosis (programmed cell death)
Reduces mitochondrial membrane permeability
49. Monitor for and Treat PBC Associated Disorders Keratoconjunctivitis Sicca
Scleroderma, CREST syndrome
Gallstones
Arthropathies:
Rheumatoid, psoriatic arthritis, Raynaud’s phenomenon, Hypertrophic osteodystrophy, Avascular necrosis, Chondrocalcinosis
Thyroid disease, renal tubular acidosis
50. PBC Associated Disorders Malabsorption
Celiac Sprue
6% of PBC patients have Celiac Sprue
3% of Sprue patients have PBC
Bile salt deficiency
Pancreatic insufficiency
51. Manage PBC Complications Standard liver disease recommendations
PBC specific symptom management
Refer for liver transplantation
52. Primary Sclerosing CholangitisRare One of the most important cholestatic liver diseases in the western world
Chronic, cholestatic liver disease characterized by
Inflammation
Obstruction
Fibrosis of both intrahepatic and extrahepatic bile ducts
53. Primary Sclerosing CholangitisPSC Many patients will progress to cirrhosis
Highly variable in and between individuals
Usually fatal important complication is cholangiocarcinoma
Etiology largely unknown, though evidence points to immune system involvement
54. PSC No specific treatment
Treatment aimed at management of disease associated conditions
Prevalence unknown
Almost half are asymptomatic at diagnosis
No specific diagnostic marker for PSC
55. PSC Clinical Features Labs:
Two- fold increase in alk phos, most have increased AST and ALT
Albumin and protime normal in early disease
Bilirubin initially normal, but gradually increases and fluctuates widely w/ extrahepatic biliary strictures, infection, obstructing stone sludge or stone
56. PSC Clinical Features Imaging
Endoscopic retrograde cholangiography is the gold standard
Magnetic resonance cholangio-pancreatography demonstrates intrahepatic duct changes
Diagnostic method of choice
Less invasive, lower risk
High cost
Claustrophobia, metal implants may preclude
58. PSC Clinical Features Histology
Liver biopsy for staging the disease
Liver biopsy to rule out other potentially treatable causes of cholestasis
59. The classic “onion” skin appearance is seen in about 13% of cases Broome & BergquistThe classic “onion” skin appearance is seen in about 13% of cases Broome & Bergquist
60. PSC Patient Presentation Large bile duct PSC may have asymptomatic elevation of LFTs. Can be cirrhotic w/ no symptoms
Symptomatic patients will have cholestasis-type symptoms plus:
Abdominal pain
Weight loss
Hepatomegaly
Acute cholangitis
61. PSCAssociated Diseases Inflammatory bowel disease, most often ulcerative colitis
These patients have increased risk for colorectal carcinoma
25% have another autoimmune disease
62. PSC Complications Related to cholestasis: pruritis, fatigue, fat soluble vitamin deficiency, osteoporosis
Related to cirrhosis: liver failure, peristomal varices
Extra-hepatic disease: IBD, pancreatitis, sprue, diabetes, thyroid disease
PSC specific
63. PSC Disease Specific Complications Fever
Abdominal pain
Dominant stricture
Gall stones
Cholangiocarcinoma
64. PSC Prognosis Factors of Importance:
Older age
Increasing bilirubin
Histological advanced stage
Child-Pugh-Turcotte Class C
65. PSC Treatment Goal Improve Quality of Life Medical support
Endoscopic treatments
Surgical interventions
Liver transplantation – PSC recurrence is more frequent than PSC
66. Case Study Asymptomatic elevation in AP noted on routine lab
Middle aged male w/ Hx ulcerative colitis on mesalamine
59 209
-----------------------------------------< 1.0
64 500
Negative viral serologies; U/S normal
MRCP reveal narrowing and strictures of intrahepatic and extrahepatic biliary tree “Pruned Tree” appearance
High risk for cholangiocarcinoma, colon cancer
Treatment is transplant
67. Reference Broome, U and Berguist. Primary sclerosing cholangitis. In Zakim and Boyer’s Hepatology: A textbook of liver disease, 5th Ed., Boyer, T.D., Wright, T.L., & Mans, M.P. Saunders Elsevier: Canada, 821-854.