Hepatitis

Dr. Meg-angela Christi M. Amores

Hepatitis

• Inflammation of the liver• Acute Viral Hepatitis• Toxic and Drug-induced Hepatitis• Chronic Hepatitis

Acute Viral Hepatitis

• Almost all cases of acute viral hepatitis are caused by one of five viral agents:– hepatitis A virus (HAV) – hepatitis B virus (HBV)– hepatitis C virus (HCV)– HBV-associated delta agent or hepatitis D virus

(HDV)– hepatitis E virus (HEV)

Hepatitis A

• Non-enveloped RNA virus• in the hepatovirus genus of the picornavirus

family • Inactivation of viral activity can be achieved by

boiling for 1 min, by contact with formaldehyde and chlorine, or by ultraviolet irradiation

Hepatitis A

• incubation period of ~4 weeks• replication is limited to the liver• viral shedding in feces, viremia, and infectivity

diminish rapidly once jaundice becomes apparent

Hepatitis A

• diagnosis of hepatitis A is made during acute illness by demonstrating anti-HAV of the IgM class

• After acute illness, anti-HAV of the IgG class remains detectable indefinitely

• patients with serum anti-HAV are immune to reinfection

Hepatitis A

Hepatitis A

• transmitted almost exclusively by the fecal-oral route

• Person-to-person spread of HAV is enhanced by poor personal hygiene and overcrowding

• contaminated food, water, milk, frozen raspberries and strawberries, green onions and shellfish

• Declining incidence in developed countries

Hepatitis B

• DNA virus• hepadnaviruses (hepatotropic DNA viruses)• Mode of transmission: – Percutaneous inoculation – intimate (especially sexual) contact and perinatal

transmission– Oral ingestion - potential but inefficient route of

exposure

Hepatitis B

Hepatitis C

• Linear, single stranded RNA Virus• genus Hepacivirus in the family Flaviviridae• Cell-mediated immune responses and

elaboration by T cells of antiviral cytokines contribute to the containment of infection and pathogenesis of liver injury associated with hepatitis C

Hepatitis C

• Mode of transmission:– Percutaneous inoculation• Transfusions• other percutaneous routes, such as injection drug use• occupational exposure to blood

– studies have failed to identify sexual transmission – chances of sexual and perinatal transmission have

been estimated to be ~5%

Symptoms and Signs

• occurs after an incubation period that varies • incubation periods for:– hepatitis A range from 15–45 days– hepatitis B and D from 30–180 days – hepatitis C from 15–160 days – hepatitis E from 14–60 days

Symptoms and Signs

• Prodromal Phase • symptoms: systemic, variable– anorexia, nausea and vomiting, fatigue, malaise,

arthralgias, myalgias, headache, photophobia, pharyngitis, cough, and coryza may precede the onset of jaundice by 1–2 weeks

– low-grade fever between 38° and 39°Cmore often present in hepatitis A and E than in hepatitis B or C

– Dark urine and clay-colored stools 1-5 days before jaundice appears

Symptoms and signs

• clinical JAUNDICE phase• liver becomes enlarged and tender • right upper quadrant pain and discomfort

jaundice

• Yellow coloration of skin, sclera, palms• visible in the sclera or skin when the serum

bilirubin value is >43 mol/L (2.5 mg/dL)• Bilirubin levels >340 mol/L (20 mg/dL)

extending and persisting late into the course of viral hepatitis – severe disease

Symptoms and Signs

• Recovery phase– constitutional symptoms disappear– some liver enlargement and abnormalities in liver

biochemical tests are still evident

– Complete clinical and biochemical recovery is to be expected 1–2 months after all cases of hepatitis A and E and 3–4 months after the onset of jaundice in three-quarters of uncomplicated, self-limited cases of hepatitis B and C

Lab Features

• serum aminotransferases aspartate aminotransferase (AST) and ALT (previously designated SGOT and SGPT) – variable increase during the prodromal phase – does not correlate well with the degree of liver

cell damage– Peak levels at time of clinical jaundice

• High bilirubin levels• Serologic tests

Diagnosis

Treatment

• antiviral therapy – not recommended in all cases of Hep B – due to complete recovery

• acute hepatitis C, recovery is rare, progression to chronic hepatitis is the rule

• interferon monotherapy • 24-week course (beginning within 2–3 months after

onset) of the best regimen identified for the treatment of chronic hepatitis C

Treatment

• most cases of typical acute viral hepatitis, specific treatment generally is not necessary

• patients will feel better with restricted physical activity

• high-calorie diet is desirable• Intravenous feeding when necessary

Prevention

• Hep A:– gloves should be worn when the bedpans or fecal

material of patients• Hep B and C:– blood precautions, i.e., avoiding direct, ungloved

hand contact with blood and other body fluids

• hand washing• Vaccination: Hep A, Hep B

Prognosis

• all previously healthy patients with hepatitis A recover completely

• hepatitis B, 95–99% of previously healthy adults have a favorable course and recover completely

• advanced age and with serious underlying medical disorders may have a prolonged course • prolonged PT, low serum albumin level, hypoglycemia,

and very high serum bilirubin values suggest severe hepatocellular disease