M33- Viral hepatitis in dentistry

Question 1

what is the chief /sole clinical manifestations of hepatitis viruses?

Answer 1

liver disease

Question 2

what is the liver involved in?

Answer 2

in the breakdown and excretion of toxins and synthesis of glucose and some proteins

Question 3

what colour is bilirubin?

Answer 3

yellow

Question 4

what are the different types of hepatitis viruses?

Answer 4

Hepatitis A virus
Hepatitis B virus
Hepatitis C virus
Hepatitis D virus
Hepatitis E virus

Question 5

who are the only people infected by hep D?

Answer 5

Infection only occurs in people already infected with Hepatitis B virus
(co infection of B and D at the same time or superinfection , of B first , then D)

Question 6

what does the infection of hep D do to the prognosis of hep B?

Answer 6

worsens the prognosis

Question 7

what are the 2 types of hepatitis?

Answer 7

• acute

- chronic

Question 8

what is acute hepatitis?

Answer 8

recent onset ( few weeks )

Question 9

what hep types can be acute?

Answer 9

Hep A, Hep B, Hep C, Hep E

In UK Hep E has become most common

Question 10

what effects does acute hepatitis have?

Answer 10

• Jaundice
• Pale stools
• Dark urine

Question 11

what are the complications of acute hepatitis?

Answer 11

-Chronic hepatitis
-Acute liver failure :
<1% of clinical cases of acute viral hepatitis

Question 12

what is chronic hepatitis?

Answer 12

-Months / years:
>definition: at least 6 months of infection
>complications after decades

Question 13

what hep types can be chronic?

Answer 13

• Hep B and Hep C, never Hep A, Hep E only if immunocompromised
• In UK Hep C is most common cause

Question 14

what can chronic hepatitis be in the early years?

Answer 14

asymptomatic

Question 15

when is chronic hepatitis picked up?

Answer 15

screening

Question 16

what are the complications of chronic hepatitis?

Answer 16

• Cirrhosis chronic liver failure
• primary liver cancer
• > 30% cases of chronic viral hepatitis will develop serious complication if left untreated for decades

Question 17

who is a patient with hepatitis referred to?

Answer 17

• physician

- notifiable

Question 18

what is the summary of Hepatitis A?

Answer 18

• Faecal oral spread
• Not blood borne
• More common in developing world
• Vaccine preventable
• Causes acute never chronic hepatitis

Question 19

what is the summary of hepatitis E?

Answer 19

• Faecal oral spread
• Not blood borne
• More common in developing world
• Not vaccine preventable
• Causes acute never chronic hepatitis (in immunocompetent)
• Can be caught in UK from some animals / meats (pigs, deer, rabbits)

Question 20

How is hep b virus and hep C virus transmitted?

Answer 20

-Blood borne spread:
>injecting drug use
>blood products
>needlestick and blood splash
-Sex :
>more for Hep B than Hep C
-Mother to child

Question 21

Name the risk groups for Hep B and Hep C in the UK.

Answer 21

-Injecting drug users (past or current)
-Greater number of sexual partners : at least for HBV
-Babies of infected mothers
-Born in areas of higher prevalence in pre-vaccine era
-Blood product exposure
: especially in unscreened blood pre-1991

Question 22

How can hepatitis be prevented?

Answer 22

• Reduce exposure

- Use vaccination

Question 23

Describe hepatitis B prevention.

Answer 23

• Clean needles and syringes for injecting drug users
• Safe sex
• Screen blood transfusions
• Vaccinate high risk groups and health care workers
• Treatment as prevention?

Question 24

Describe hepatitis C prevention.

Answer 24

• Reduce exposure as for Hep B
• No vaccine is available
• Treatment as prevention?

Question 25

what is the treatment of chronic viral hep B?

Answer 25

Numerous antivirals now available, they are suppressive rather than curative, so lifelong therapy required. Fairly safe therapy.

Question 26

what is the treatment of chronic viral hep C?

Answer 26

-Combination of 2 or 3 antivirals will cure >90%: >precise antivirals used depends on genotype of virus (1 to 6) >rapidly developing field, many new antivirals in recent years -Significant side effects of early regimes being reduced by new combinations -Antivirals given in short courses a few months long -Reinfection possible

Question 27

what does the decision to treat what patient depend on?

Answer 27

Which patients to treat depends on clinical evaluation to determine who is at most risk of progressing to complications of chronic infection

Question 28

what is important to remember in reducing exposure during health care?

Answer 28

- Standard precautions | - Unreasonable to expect to identify all individuals with a blood borne virus infection

Question 29

what actions are used to reduce exposure during health care?

Answer 29

- Wear gloves - Mask and eye protection may be appropriate - Correct disposal of sharps - Good sterilisation (autoclave) or use of single use devices - Vaccination against Hep B - Disinfect surfaces (with e.g. hypochlorite)

Question 30

what lab test can be used for hepatitis ?

Answer 30

Clotted blood (gold top bottle)

Question 31

what is tested in labs for the presence of Hep B acute or chronic?

Answer 31

- HBsAg (Hepatitis B surface antigen) | - All HBsAg +ve people are best considered to be infectious

Question 32

who is more likely to progress to complications soon in Hep B?

Answer 32

those that either present (in addition to HBsAg) Hep B DNA are very infectious

Question 33

what is present in those that have been successfully vaccinated and in those that have completely recovered from acute hep B?

Answer 33

Anti-HBs (antibody to HBsAg)

Question 34

who has anti- HCV (antibody to hep C virus)?

Answer 34

present in people with acute or chronic infection but also in those who have recovered

Question 35

why are all anti-HCV +ve people considered infectious?

Answer 35

Only a minority recover spontaneously

Question 36

what is the lab test for hep C?

Answer 36

- Hep C RNA test (Hep C PCR test) | - Positive in infected anti-HCV +ve people but not in those that have recovered

Question 37

Describe the fitness to practice for hepatitis.

Answer 37

- Must be HBsAg negative :Or if positive must have HBV DNA at very low level (<200 IU/mL) in blood - Must be Hepatitis C virus antibody negative :Or if positive must be Hepatitis C RNA negative