Hepatitis B(Clinical
aspect)
Clinical features
— Generally asymptomatic
— Prodormal illness (<2weeks)
includes:
fever, chills, headache, myalgia,
arthalgia, nausea and anorexia.
— Icteric phase
dark urine with yellow
discoloration of sclera , pale stool.
accompanied by vomiting, diarrhea
and abdominal pain.
— Recovery phase (3-6 weeks):
improved apetite, GI symptoms
subside, jaundice decreases.
Physical
signs
— Liver
tender and minimally enlarged
— Spleen
splenomegaly
— Lymph nodes
cervical lymphadenopathy
Complications
— Acute liver failure
— Aplastic anemia
— Relapsing hepatitis
— Chronic liver disease
progression to chronicity
i. Vertical
transmission- 90%
ii. Horizontal
transmission- 10%
— Cirrhosis
— Hepatocellular carcinoma
— Renal failure
— Henoch-Schonlein Purpura
Poor
prognostic features
— Marked increase in AST and ALT
— Bilirubin >20mg/dl
— Liver not enlarged
— PT prolongation by 5 seconds
— Recurring attacks of hypoglycemia
— Renal failure
— Associated conditions
Investigations
— Immunological tests
detection of the viral antigens and
the host antibodies against them
i.
HBs Ag
viral surface antigen
active infection
appear late in IP before the
prodormal stage at about 3-4 weeks and
disappear by 5 months
ii. HBc Ag
viral core antigen, not found in
blood
denotes a recent infection
iii. HBe Ag
indicate active viral replication
in liver and infectivity
detected early in course
iv. Anti HBc
Ag
IgM type with IgG Ab
first antibody to appear,
persist life long
v. HBs Ag and anti HBc(IgG) in blood denote
progression to chronicity.
vi. HBV-DNA
by polymerase chain reaction
measures viral load and active
viral replication
Laboratory tests
i. liver
function tests
- raised bilirubin level
(conjugated and unconjugated)
- raised aminotransferses (ALT and
AST)
- ALP level may be raised but less
than twice the normal.
ii. Low total count with neutropenia, relative
lymphocytosis
and atypical lymphocytes.
iii. Urine shows bilirubinemia, slight
microscopic
hematuria and mild proteinuria.
iv. Marked prolongation of prothrombin time
signifying
extensive hepatocellular damage.
Management
no specific t/t, only supportive with
monitoring for ALF.
full recovery in (90-95)% and (5-10)%
chronicity for life.
— Rest
complete rest during the symptomatic
phase
gradual ambulation.
— Diet
2000-3000Kcal/day, light diet, fruit
drinks and glucose
protein diet
i.v. fluids in case of severe
vomiting.
— Drugs
use of any other drugs (sedative and
hypnotics) is avoided.
alcohol avoided for about 6 months.
OCP is resumed after clinical and biochemical recovery.
Antiviral drugs for Hepatitis B
Infection
— Interferon-α
- augment native immune response
- c/i
in cirrhosis
— Lamivudine
- inhibit DNA polymerase
- effective in improving liver
function in pt with
decompensated cirrhosis.
— Adefovir
- inhibit DNA polymerase
— Entecavir and Telbivudine
- decrease viral load
- used in chronic hepatitis
Prevention
— Active immunization
recombinant vaccines containing
HBsAg
i.m. injection at 0, 1 and 6
months.
1o µg for <1o yrs and 2o µg for
>10 yrs.
recommended- all
children along with high risk groups as health
workers, hemodialysis pts, injection and
drug users, hemophiliacs
sexual contact of HBsAg carriers.
— Hyperimmune B immunoglobulin (HBIG)
prepared from blood containing
anti-HBs.
given within 24 hrs or at most a week
of exposure.
dose - 0.06ml/kg
indication- accidental needle
puncture, gross personal
contamination with infected blood,
oral ingestion or
contamination of mucosal membranes
and exposure to cuts
or grazes.
— Active-passive immunization
given together with Hyperimmune
globulin
recommended for post
exposure prophylaxis in unvaccinated.
Perinatal exposure to infants to
HBsAg positive mother– a single
dose of 0.5 ml of HBIG in thigh
immediately after birth is followed
by 3 doses of vaccine within 12 hrs
of birth.
— Others
screening of blood donors for HBV
infections.
voluntary blood donation.
use of sterilized instruments while
handling blood and body
fluids
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