chapter 31 Flashcards
bilirubin
organic yellow pigment formed in liver by breaking down hemoglobin and is excreted in bile
Conjugated bilirubin
Once in the liver, bilirubin becomes conjugated. This means it is water-soluble and can be excreted. Unconjugated bilirubin is toxic
Liver basics
- uses enzymes and O2 to burn toxins, especially fatty ones
- the toxins are combined w amino acids so they can be removed from the liver through the bile or urine
Hepatitis A Virus (HAV)
-Transmitted by the fecal-oral route
-Virus shed in feces
-Virus killed by thorough cooking
-Fever, abdominal pain, mild flu-like symptoms
-Vaccine available (Havrix)
-Endemic (routinely found) in Asia, Africa, Mexico, and -South America
-Treatment
-Supportive
Hepatitis B Virus (HBV)
-Transmitted by blood products, body fluids, or sexual contact
-Does not directly kill cells, but the host’s immune system destroys viral-infected cells
Hepatitis Signs and Symptoms (General)
-Fever
-Abdominal pain
-Flu-like symptoms
-Nausea and vomiting
-Fatigue
-Malaise
-Myalgias
-Arthralgias
-Mild headache
-Anorexia
-Loss of taste for food
-Smokers often lose their taste for tobacco
-Hepatomegaly
-Jaundice
-Stool that may have a pale appearance
-Dark urine
-Pruritus
Hepatitis B Virus Stage 1
-Incubation period
-No signs or symptoms, however, can infect others
-Duration of 2 to 4 weeks
Hepatitis B Virus Stage 2
-The inflammatory reaction of hepatocytes
-Flu-like symptoms and jaundice
-HBeAg, HBsAg, and HBV DNA can be detected in the bloodstream
-Liver enzymes begin to increase
-Duration 3 to 4 weeks
Hepatitis B Virus Stage 3
-Immune system reaction to HBV
-Viral replication slows
-HBV DNA levels are lower or undetectable
-Liver enzyme levels decrease to norma
Hepatitis B Virus Stage 4
The virus cannot be detected
Antibodies to HBsAg, HBcAg, and HBeAg
Antibodies against HBsAg confer long-term protective immunity
Anti-HBcAg only with infection, not vaccination
HBV Signs and Symptoms
-Anorexia
-Nausea and vomiting
-Fatigue
-Flu-like symptoms
-Fever, malaise, myalgias
-Jaundice
*Hepatomegaly
*Splenomegaly
*Lymphadenopathy
-Spider angioma
-Palmar erythema
-Jaundice can last for months
-Patients with severe cases of infection may show signs of hepatic encephalopathy—somnolence, confusion, stupor, or coma.
HBV Diagnosis
-Presence of HBsAg in the bloodstream
-Levels do not correlate with disease severity
-IgM-type anti-HBc antibodies
-Acute infection
-IgG-type anti-HBc antibodies
-Chronic infection
HBV Treatment
-Based on symptoms
-Supportive with rest
-Small, high-calorie, and high-protein meals
-Interferon alpha
-Prevention is key
HBV Extra Info
-Course is variable
-Most do not recover completely
-Chronic HBV
Can be healthy carriers without disease evidence
-Can lead to hepatocellular cancer
-Contacts can obtain HBIg (rapid, passive immunity)
Hepatitis C virus (HCV)
-Acute infection usually mild
-Most develop chronic hepatitis
Can remain dormant for years before symptoms
-Long incubation period
2 weeks to 8 months
-Patient is asymptomatic, can spread the virus
Transmitted via blood: IV drug use
-HCV-RNA
Detected weeks to months before antibody development
-Virus mutates rapidly
No vaccination