Download Hepatitis .L 36-37

Hepatitis:
Causes , Symptoms, Diagnosis
Treatment & Prevention .
Viral Hepatitis in Children
Virus causes:
Hepatotropic
and
non - hepatotropic
•Hepatotropic viruses:
HAV, HBV, HCV, HDV, HEV, HGV
Hepatitis A Virus Infection
Worldwide infection
Transmission
Fecal-oral route
• Close personal contact
• Contaminated water and food
Parenteral
(rare)
Incubation: 15-50 days (mean 28)
Pathogenesis
HAV infection is biphasic process:
• Non-cytopathic stage
• Cytopathic stage
Hepatocellular damage is immune mediated process
and not direct cytopathic effect by hepatitis A virus.
Clinical manifestations
HAV infection is an acute self-limited illness
• General nonspecific symptoms (fever, malaise, anorexia,
vomiting, nausea, abdominal pain and diarrhea)
• Jaundice
• Choluria (bilirubin in urine)
• Mild hepatomegaly
Symptomatic hepatitis: 30% of infected children younger than
six years.
70 – 80% in older children and adults infected with HAV
Atypical presentations
Hepatic manifestations:
• Relapsing hepatitis (3-20%)
• Acute liver failure (<1%)
• Cholestasic hepatitis (30% of adult).
• Autoimmune hepatitis.
Extra-hepatic manifestations (common)
• An evanescent rash (11%)
• Arthralgia (14%)
Atypical presentations
Extra-hepatic manifestations (rare)
• Vasculitis
• Arthritis
• Optic neuritis
• Transverse myelitis
• Encephalitis
• Bone marrow suppression
Diagnosis
Serologic tests:
• Anti HAV IgM : indicates an acute infections
• Anti HAV IgG : indicates resolved infections or
vaccine induced immunity
Other techniques:
• HAV detection in stool and body fluids by electron
microscopy.
• HAV RNA detection in stool, body fluids, serum and liver
tissues by PCR.(Polymerase chain reaction)
Treatment
 Self-limited disease, rarely requires hospitalization
 Only supportive measures in uncomplicated cases:
• Bed rest.
• Control fever.
• Increased fluid intake.
• No particular diet is needed.
• Limit hepatotoxic medications,
( acetaminophen)
 Children with HAV infection should be away for 1 wk.
Treatment (cont.)
If complicated with acute liver failure:
• Hospitalization
• Aggressive supportive therapy
• Early transfer to liver transplantation center.
If HAV triggered secondary disorders
• Treat the specific disease
Prevention and Prophylaxis
General measures:
• Adherence to sanitary practices (hand washing).
• Heating food appropriately.
• Avoidance of water or food from endemic areas.
Active immunization:
Two hepatitis A vaccines (inactivated vaccines)
• HAVRIX (in1995)
• VAQTA (in 1996)
Passive immunization:
• Polyclonal serum immunoglobulin (IgG)
Hepatitis A Vaccines
 Pediatric and adult formulations :
• Pediatric formulations vaccines approved for
12 months through 18 years
• Adult formulations approved for persons 19 years
and older
Hepatitis A Vaccines
•Adult
 1 dose ( >95% seropositive )
 booster dose 6-18 months after first dose ( 100%
seropositive )
•Children older than 2years of age


1 dose ( >97% seropositive ) in (18 m. ) of age
booster dose 6-12 months after first dose ( 100%
seropositive )
Polyclonal serum immunoglobulin (IgG)
• Passive immunity lasts for up to six months
• Effective if administered within 2 weeks post-exposure
• Dose is 0.02 ml per kg IM
Hepatitis B Virus
Incubation Period of HBV
• Average: 60–90 days
• Range: 45–180 days
Clinical manifestations
Acute Infection:
• Asymptomatic
• Symptomatic : Prodromal (serum sickness
like syndrome, Constitutional (anorexia,
nausea, jaundice, right upper quadrant
pain, fatigue)
•Occasionally develops acute fulminant
hepatitis.
Clinical manifestations
Chronic Infection:
•Asymptomatic
•Vague right upper quadrant pain and fatigue
•Occasionally associated with extrahepatic
manifestation including
polyarteritis nodosa and
glomerulonephropathy
Diagnosis of Hepatitis B V
•Tests for HBV replication
including
HBeAg and HBeAb.
•Screen for hepatocellular carcinoma with (HCC(
1- abdominal ultrasound
2-serum alpha fetoprotein.
•Liver biopsy for patients who meet criteria of chronic
hepatitis and who are considered for treatment
Serologic responses to hepatitis B Virus infection
Progression to chronic state
 90% if perinatal acquisition
 20-50% if acquired between
1-5 years of age.
 <5% if acquired in adult
Treatment
Interferon alfa
•First line treatment choice.
•Six month course of interferon alfa-2b, six
million units (MU) per m2 (maximum 10MU)
SC. three times a week for 24 weeks.
•Response rate in 30 – 40% of patients.
•Side effects: Flu like symptoms, Bone
marrow suppression
Treatment
Lamivudine
•Second line treatment choice
•Dose: 3 mg per kg of body weight (max. 100
mg)
•Drug resistance with long term use
Treatment
Newer agents
•Pegylated interferon therapy approved for ≥ 3
years of age.
•Adefovir : licensed for use in patient ≥ 12 years
of age.
•Tenofovir : licensed for use in patient ≥ 12
years of age.
•Entecavir: licensed for use in patient ≥ 16 years
of age.
Prevention
HBV vaccine
•Universally recommended for all infants. 4 doses
in (0,2,4,6 ) months of age .
•HBV - exposed family members or closed contacts.
HB immune globulin (HBIG )indication for use
•Infants born to HBsAg positive mothers.
•Post exposure prophylaxis within 24 hours of exposure if no past
vaccine.
Prevention
Other measures
• All pregnant women should antenatal screening for
HBsAg.
• Investigations for HBV ,HCV and HIV before any
surgical intervention
• Household contacts:
Avoid sharing of tweezers,
shavers,
toothbrush, nail clippers.
•Universal precautions for handling abrasions,
bleeding, etc.
Monitoring of patients
Disease activity:
•ALT every 6-12 months
•HBeAg and HBeAb every 12 months
•If HBeAg is +ve, measure HBV DNA.
hepatocellular carcinoma surveillance:
•Ultrasound of liver every 12 months
•Alpha fetoprotein every 12 months
Mode of transmission
• Vertical
• Parenteral
• Sexual
Perinatal transmission
•Perinatal transmission rates are 5%
•Rates are increased up to 15 – 20% if mother is co-infected with
HIV.
•Risk factors:
Use of internal fetal monitoring devices
Prolonged rupture of membranes (>6 hours)
High viral load
HIV co-infection
•Breast feeding and vaginal delivery does not increase
vertical transmission
Approximately 90% of transfusion-associated hepatitis
is caused by HCV
Clinical Features
•Incubation period: 30-150 days
•Chronic infection will develop in 60-80% of exposed children.
Patients with chronic HCV infection are at risk for developing
cirrhosis, liver failure, and liver cancer
•Majority of patients are
asymptomatic in childhood.
•End-stage liver disease with decompensated cirrhosis has been
described in children.
•Acute liver failure from HCV infection has not reported
in immunocompetent patients.
•Comorbidities: Glomerulonephritis,
Cryoglobulinemia
Autoimmune hepatitis
Diagnosis
•Check liver panel
•Screen with HCV IgG antibody after 18
month of age and
HCV RNA after 2 month of age.
•HCV genotype analysis indicated
treatment is being considered.
if
Treatment
•Subcutaneous weekly pegylated interferon-alpha
injections for 48 weeks (genotypes 1 or 4)
or 24 weeks (genotypes 2 or 3), plus oral ribavirin.
•Treatment response: non detectable HCV RNA by 24
weeks.
•Pegylated interferon/ribavirin therapy approved
for ≥ 3 years of age.
Prevention
•HCV vaccine: none available.
•HCV immunoglobulin: none available.
•Household contacts: avoid sharing of tweezers,
shavers, toothbrush, nail clippers.
•Universal precautions for handling abrasions,
bleeding, etc.
( Patients with chronic HCV infection can continue to
infect others. )
•Screening for hepatocellular carcinoma (HCC)
HEPATITIS D VIRUS
•Defective interfering virus, requires HBV co-infection
HDV cannot survive on its own because it requires a protein
the HBV makes , to enable it to infect liver cells.
•Prevalent in Mediterranean basin,
North Africa, and South
America
•10% of HBV infected persons co-infected with HDV
Hepatitis D virus (HDV) infections occur only in those who are infected with
HBV.
•Diagnosis: Co-infection with acute HBV showed
positive IgM anti-HDV,
while super-infection of chronic HBV showed
positive IgG & IgA anti-HDV in addition to
serological markers of HBV.
The dual infection of HDV and HBV can result in a
more
serious disease and worse outcome.
Hepatitis B vaccines provide protection from HDV infection.
HEPATITIS E VIRUS
•Incubation
period 15-60 days
•Enteric transmission via fecal-oral route.
•Endemic in Southeast & Central Asia;
Middle
East, North and West Africa
•Acute, self-limited hepatitis
HEPATITIS E VIRUS
•Clinical features range from asymptomatic to
mild to fulminant picture with high mortality
rate in pregnant women in third trimester
(20%)
•Diagnosis: Anti-HEV IgM positive for 2-3
months, Anti-HEV IgG persists long term in
half of patients.
•Immunoprophylaxis : none
HEPATITIS G VIRUS
• RNA virus.
• Parenterally transmitted agent,
can be transmitted perinatally .
●
virus (HGV)
was recently discovered and resembles HCV.
the virus and its effects are under investigation,
and its role in causing disease in humans is
unclear.
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