The document discusses hepatitis, which is inflammation of the liver. It outlines the various causes of hepatitis including viruses, chemicals, drugs, and autoimmune diseases. It focuses on the different types of viral hepatitis (A, B, C, D, E), their symptoms, modes of transmission, risks, and ability to cause both acute and chronic conditions. Hepatitis B and C are particularly discussed as leading causes of chronic liver disease and liver cancer worldwide.

1. Hepatitis Inflammation of the liver

2. Causes of Hepatitis Reactions to chemical agents, drugs & toxins Autoimmune diseases Viruses

3. Acute Viral Hepatitis Hepatitis A, B, C, D, E Hepatitis B is 9 th leading cause of death in the world 75% of those chronically infected with Hep B live in the Asia-pacific region In NZ approx 1% of population has been exposed to the Hep C virus Approx 40% of HIV infected pts have Hep C virus

4. Hepatitis A Usually transmitted through faecal-oral route Can occur sporadically but frequently occurs in small outbreaks caused by faecal contamination of food or drinking water Also spread by drinking contaminated milk & eating shellfish from infected waters

5. Hepatitis A (cont.) Present in the blood only briefly Virus replicates in liver, excreted in bile & shed in the stool Found in faeces 2 or more weeks before the onset of symptoms & up to 1 week after the onset of jaundice

6. Risk factors for Hep A People travelling overseas who have not previously been exposed to virus Young children are asymptomatic therefore play important role in spread of disease Institutions housing large numbers of people Oral behaviour & lack of toilet training promote spread in daycare centres

7. Clinical Manifestations Abrupt onset Fever Malaise Nausea Anorexia Abdominal discomfort Dark urine Jaundice Children under 6yrs usually asymptomatic Symptoms last approx 2 mths but can last longer

8. Hepatitis B More serious health problem than Hep A Highest rate of disease occurs in 20 – 49 year age group Incidence is decreasing because of Hep B vaccine Can cause chronic hepatitis, cirrhosis of liver, liver necrosis & a carrier state 30% asympotomatic

9. Mode of Transmission Inoculation with infected blood or serum Found in body secretions so can be transmitted by oral or sexual contact Highly prevalent among injecting drug users, persons with multiple sexual partners & men who have sex with men

10. Hepatitis B Health care workers are at risk because of exposure to blood & needle stick injuries Virus can be spread through blood/blood products transfusion 2 – 10% of adults infected with hep B become chronic carriers & may transmit the disease Chronic carriers may have normal liver, low grade or severe liver disease & are at greater risk of liver cancer

11. Hepatitis C Most common cause of chronic hepatitis, cirrhosis and liver cancer Many are unaware they are chronically affected because they are not clinically ill Infected persons serve as source of infection to others & are at risk of chronic liver disease during 2 or more decades after infection

12. Hepatitis C Injecting drug use most important risk factor Transmission of small amts of blood during tattooing, acupuncture & body piercing Incidence of sexual & mother-to-child transmission is uncertain Occupational exposure due to needle stick injuries

13. Hepatitis C Incubation period 15-150 days (average 50 days) Clinical symptoms milder than other types of viral hepatitis Can be asymptomatic Non-specific – fatigue, malaise, anorexia, weight loss Jaundice uncommon

14. Hepatitis C High rate of persistence Able to induce chronic hepatitis and cirrhosis Increases risk of liver failure *No vaccine that protects against Hep C

15. Phases of Hepatitis Preicteric Precedes jaundice, lasts 1-21 days Period of maximum infectivity for hep A Anorexia, nausea, vomiting R) upper quadrant abdominal discomfort Constipation or diarrhoea Malaise, headache, low grade fever, arthralgias, skin rashes

16. Icteric Phase Lasts 2-4 weeks & characterised by jaundice Jaundice Pruritus (accumulation of bile salts under skin) Dark urine (excess bilirubin excreted by kidneys) Light or clay coloured stools (obstruction of bile ducts) Fatigue, weight loss

17. Posticteric Phase Begins as jaundice is disappearing & lasts weeks to months (average 2-4mths) Malaise, easy fatigability Hepatomegaly Relapses can occur Disappearance of jaundice does not indicate total recovery

18. Chronic Hepatitis Inflammatory reaction of liver of more than 3 – 6 months duration Chronic viral hepatitis ranks as chief reason for liver transplants in adults Clinical features highly variable Most common – fatigue, malaise, anorexia, bouts of jaundice No simple & effective treatment

19. Jaundice Results from abnormally high accumulation of bilirubin in the blood A yellowish discolouration to the skin & deep tissues Becomes evident when serum bilirubin is above 40 µg/L (normal 5-20µg/L) Often hard to detect in persons with dark skin

20. Jaundice Usually first detected in sclera of eye

21. Jaundice

22. Causes of Jaundice Excessive destruction of RBCs Impaired uptake of bilirubin by liver Decreased conjugation of bilirubin Obstruction of bile flow in liver or bile ducts