hepatitis pptx - unknown

THREE PHASES OF “CLASSIC” HEPATITIS

PRODROMAL PHASE
Flu-like symptoms
ICTERIC PHASE
Jaundice
CONVALESCENT PHASE
Recovery

LAB TESTS
Liver enzymes:
Alanine aminotransferase (ALT) and aspartate aminotransferase (AST)
10 TO 100 FOLD INCREASE CAN BE EXPECTED

LAB TESTS

SERUM BILIRUBIN: hyperbilirubinemia
LEVELS MUST APPROACH 3mg/100ml TO
MANIFEST AS JAUNDICE
JAUNDICE OFTEN FIRST MANIFESTS IN SCLERA

LAB TESTS

Prothrombin time:
HIGHER THE PROTHROMBIN TIME (PT), THE
MORE SEVERE THE HEPATIC DAMAGE

HEPATITIS TYPE A (HAV)

SINGLE-STRANDED RNA
VIRUs
SPREAD MAINLY BY ORAL-FECAL
ROUTE
INCUBATION PERIOD 15-50 DAYS

HAV
Usually disease of young but can affect adult.
OFTEN ASYMPTOMATIC
ILLNESS USUALLY SELF-LIMITING RECOVERY IS COMPLETE and does not need any specific treatment
NO EVIDENCE OF CHRONIC FORM OR CARRIER STATE OF HAV

Prevention

TWO-DOSE VACCINE
6 MONTHS APART
AVAILABLE SINCE 1994
HEALTH CARE PROVIDERS -RECOMMENDED

Hepatitis B virus

Hepadnaviridae member
100 times more infectious than HIV
10 times more infectious than HCV
The most common carcinogen after tobacco in man

Schaefer S. World J Gastroenterol. 2007;13:14–21. European Parliament. Hepatitis B: Revealing a Silent Killer. Workshop at the European Parliament, 2006. Available at: http://www.ilcuk.org.uk/files/pdf_pdf_36.pdf. NIH 11th report on carcinogens 2004. Available at: ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s092thpb.pdf.

HEPATITIS B (HBV)
CAN CAUSE ACUTE / AND A CHRONIC HEPATITIS
Can also cause CARRIER STATE
40 - 180 DAY INCUBATION PERIOD
MANY CASES ARE SUBCLINICAL AND MOST ARE ANICTERIC

Concentration of Hepatitis B Virus in Various Body Fluids

High concentration blood serum wound exudates
Moderate concentration semen vaginal fluid saliva
Low/Not Detectable urine feces sweat tears breast milk

Mode of spread

Mainly by parenteral route
DIRECT PERCUTANEOUS INOCULATION OF INFECTED SERUM OR PLASMA
INDIRECTLY THROUGH CUTS OR ABRASIONS
ABSORPTION THROUGH MUCOSAL SURFACES
ABSORPTION OF OTHER INFECTIOUS SECRETIONS (SALIVA OR SEMEN)

WHO IS AT GREATEST RISK FOR HBV INFECTION?
LAB PERSONNEL WORKING WITH BLOOD PRODUCTS
MEDICAL/DENTAL PERSONNEL
IV DRUG ABUSERS
BLOOD PRODUCT RECIPIENTS

Clinical Features

Can be asymptomatic (subclinical)
Symptomatic case pass through 3 phases:
Prodromal phase
Icteric phase
Recovery phase
Persistence of infection beyond 6 months indicate progression to chronic phase

Diagnosis

Serological:
Detection of HBV antigen and antibodies.

Serological markers for hepatitis B

• Name
• Abbreviation
• Definition/Comment
• Hepatitis B surface antigen
• HBsAg
• Antigen indicating infection
• Hepatitis B e antigen
• HBeAg
• Antigen correlating with hepatitis B replication and infectivity
• Hepatitis B surface antibody
• Anti-HBs
• Usually indicates immunity
• Hepatitis B e antibody
• Anti-HBe
• Presence in serum of persons with chronic hepatitis B infection indicates low titre of hepatitis B
• Hepatitis B core antibody
• Anti-HBc
• Indicates previous or ongoing infection with hepatitis B
Mahoney .Clin Microbiol Rev. 1999;12:351–366. http//www.ashm.org.au/uploads/B_Positive-Glossary_abbreviations.pdf.

Outcome of Infection
COMPLETE RESOLUTION IN 6 MONTHS (95% of adults)
Chronic infection
5% ADULTS CHRONIC CARRIERS
20% CHILDREN CHRONIC CARRIERS
80-90% NEONATES AND INFANTS BECOME CHRONIC CARRIERS

PREVENTION

1. PASSIVE IMMUNITY:
INJECTION OF IMMUNE GLOBULIN (HBIG)
• TRANSFERRING PREFORMED ANTIBODIES FROM AN IMMUNIZED HOST TO A PERSON IN NEED OF IMMUNITY
PROTECTION IS TRANSITORY, BUT ONSET IS IMMEDIATE

2. ACTIVE IMMUNITY

Using HBV vaccine
Act BY STIMULATING OWN IMMUNE RESPONSE using HBV vaccine
PROTECTION AFTER LATENT PERIOD
LONG-TERM IMMUNITY IS PROVIDED

The Hepatitis C Virus

Spherical, enveloped, single-stranded RNA virus
Family Flaviviridae
HCV may produce ~ 1 trillion new viral particles each day

Hepatitis C: Basic Facts

Hepatitis C is a global health problem affecting over 170 million people worldwide.
Hepatitis C is a leading cause of end-stage liver disease and hepatocellular carcinoma.

HEPATITIS C (HCV)

SPREAD MAINLY BY PARENTAL ROUTE
ACCOUNTS FOR 90-95% OF POST TRANSFUSION HEPATITIS

Sources of Infection forPersons with Hepatitis C

Sexual 15%
Other* 5%
Unknown 10%
Injecting drug use 60%
Transfusion 10%
(before screening)
* Hemodialysis; health-care work; perinatal
Source: Centers for Disease Control and Prevention

WHO IS AT GREATEST RISK FOR HCV INFECTION?

LAB PERSONNEL WORKING WITH BLOOD PRODUCTS
MEDICAL/DENTAL PERSONNEL (3-10% VIA NEEDLESTICK FROM INFECTED PATIENT)
IV DRUG ABUSERS
BLOOD PRODUCT RECIPIENTS
HEMODIALYSIS PATIENTS

Clinical features

30-180 DAY INCUBATION PERIOD
Acute infection can be asymptomatic.
Symptomatic cases present through 3 clinical phases

Outcome

• UP TO 90% = CHRONIC CARRIERS

Diagnosis
HCV antibody
HCV RNA (PCR)
A positive antibody test should be repeated for confirmation

TREATMENT of Viral Hepatitis

HAV and HEV- ACUTE: SYMPTOMATIC
HBV - ACUTE: SYMPTOMATIC
CHRONIC: Antiviral agents
HCV - ACUTE: SYMPTOMATIC
CHRONIC: COMBINATION INTERFERON ALPHA and RIBAVIRIN

 SOURCE: RN December 1997

COMPLICATIONS
HAV - RELAPSE; IN RARE CASES - FULMINANT HEPATITIS
HBV - CHRONIC LIVER DISEASE INCLUDING CIRRHOSIS, PRIMARY HEPATOCELLULAR CARCINOMA AND FULMINANT HEPATITIS
HCV - CHRONIC LIVER DISEASE INCLUDING CIRRHOSIS, PRIMARY HEPATOCELLULAR CARCINOMA

Dental Management:

Difficult to identify all patient through history

Many acute cases of Hep B and C are mild

MUST use universal precautions for all

Screening recommended for patients from

high risk groups

Viral Hepatitis: A,B,C,D,E

Guidelines for blood exposure

From patients with Hepatitis B:

1. Determine the titrer of anti-HBs in the health
care professional

If adequate: no treatment is needed

If inadequate give Hepatitis B Immunoglobulin

Viral Hepatitis:
Guidelines for blood exposure

From patients with Hepatitis C

Exposed professional gets baseline and

follow up testing for anti-HCV and liver

enzymes

Viral Hepatitis:

Guidelines for blood exposure

From patients with Unknown

Ask for serological testing of the patient

(this can be ordered by the Medical

Officer)

The presence of HCV-RNA in saliva provides a biological basis for saliva as
a possible source of HCV infection,
Dentists were in a high risk of contracting this disease due to the procedures and instruments of dental
treatment.