Hepatic Flashcards
Liver anatomy
Located behind the ribs in the upper right abdominal cavity
Normally it is not palpable
Consists of two larger lobes and two smaller lobes
Able to regenerate
Liver circulation
Circulation is of major importance to liver function
75% of the blood supply comes from the portal vein which drains the GI tract (nutrients)
25% comes from the hepatic artery (oxygen)
Hepatic vein drains the liver and empties into the IVC
Hold approximately 450ml of blood
Liver function
Glucose, fat, protein, and drug metabolism
Conversion of ammonia to urea
Vitamin and iron storage (A, D, K, E, B12)
Bile formation
Bilirubin excretion
Liver function tests
Alanine aminotransferase (ALT)- Best indicator for liver injury Aspartate aminotransferase (AST)- Also elevated with damage to the heart, skeletal muscle, kidney, and pancreas Alkaline phosphatase (ALP)- Elevated in severe liver or biliary disease Gamma-glutamyl transpeptidase (GGT)- Increases 12-24 hours after heavy alcohol consumption
Hepatitis A transmission
Transmission is usually through fecal-oral route:
1. Contaminated drinking water
2. Food contaminated by infected person who did not wash their hands after going to the bathroom
Sexual transmission
Transfusion of infected blood
Incubation period is 4-6 weeks
Found in feces up to 2 weeks before symptoms occur and 1 week after
Can be contagious up to 3 months after
Hepatitis A symptoms
Generally mild or absent: Fever, fatigue, loss of appetite, N&V, abdominal pain, jaundice, joint pain
Treatment is supportive in nature
No long term liver damage and chronic state is unknown
Long-term immunity against further infection
Vaccine available
Hepatitis B transmission
Found in blood, semen, cervical secretions, saliva, and wound drainage
Transmission is through direct contact with blood and blood products, sexual contact, contact with contaminated objects
Transmission can occur from pregnant mother to child if infected in third trimester or at birth
High risk groups: healthcare workers, IV drug users, homosexual men, people with multiple sex partners
Incubation is 6 weeks to 6 months, transmission possible
Hepatitis B symptoms
Symptoms are similar to HAV
Hallmark signs are joint pain, high fever, and rash
95% will resolve and have immunity
Can exist as an asymptomatic carrier state or chronic active state especially in those who are immunocompromised
Rarely progresses to liver failure
Increased risk of hepatocellular carcinoma
Vaccine available
Hepatitis C etiology
Accounts for
-40% of cases of end-stage cirrhosis
-60% of hepatocellular carcinoma
There are about 100 different strains, which makes development of a vaccine difficult
Hepatitis C transmission
Found in blood, blood products, transplanted tissue
Transmitted through contact with blood and blood products.
Can be sexually transmitted
Most common transmission route in the US is IV drug use (48%)
Hepatitis C symptoms/carriers
15% to 25% of cases spontaneously clear the acute infection, The rest develop chronic infection
Can exist as an asymptomatic carrier
Incubation period is 35 to 72 days
Symptoms include fatigue, fever, anorexia, weight loss, and abdominal pain
May be asymptomatic
Often not diagnosed until signs of cirrhosis emerge
Hepatitis D
Requires a simultaneous infection with HBV for replication
Transmitted through blood and body fluids
Incubation lasts for 1 to 6 months
IV drug users have a high rate of HDV infection
Symptoms are the same as HBV infection but may be more severe
Infected are more likely to progress to chronic active hepatitis and cirrhosis
Hepatitis E
Uncommon in the US
Found in Southeast Asia, India, North Africa, and Mexico
Globally there are 20 million cases per year
Transmitted through fecal-oral route
Incubation period 15 to 60 days
Symptoms are similar to HAV
Usually self-limiting but can lead to severe sudden liver failure
Vaccine available
Hepatitis G
Not much is known about this virus
Transmission is through the skin or through sexual contact
Most infected are asymptomatic and incubation time is unknown
Been detected in 50% of IV drug users, 30% of hemodialysis clients, and 15% of those with HBV or HCV
Those with HIV that are also infected with HGV have improved survival rates. It is thought that HGV inhibits HIV reproduction
Hepatitis pathophysiology
Inflammation and edema of the liver
This obstructs the bile canaliculi and causes obstructive jaundice
Liver cell necrosis, hyperplasia, and scarring
In mild cases there is little damage
Normally a chronic and slow process
There are rare cases of acute sudden and sever hepatitis caused by a co-infection of HBV and HDV
Liver regeneration begins within 48 hours after tissue injury
Hepatitis clinical phase 1
Prodromal phase
- Exposure to appearance of jaundice
- Vague flu like symptoms with anorexia, nausea, vomiting, abdominal pain, malaise, fever, RUQ pain
Hepatitis clinical phase 2
Icteric phase
- Begins with appearance of jaundice, usually 5-10 days after initial symptoms. Some have no jaundice
- Increase in the symptoms of the prodromal phase
- Ends with progressive clinical improvement
Hepatitis clinical phase 3
Convalescent phase
- Increased sense of well-being, jaundice is resolved, usually after 2-3 weeks of acute illness
- Time to full recovery varies
Hepatitis diagnostic labs
Liver function tests -AST (8-48 wnl) -ALT (7-55 wnl) -ALP (45-115 wnl) -Bilirubin (0.1-1.2 mg/dL wnl) Serological tests for viral antigens, antibodies, or the virus itself
Hepatitis liver biopsy
Done to evaluate type of liver disease or if cancer is present
Percutaneous procedure using CT or ultrasound
After procedure – keep patient lying on right side for minimum of 2 hours to splint puncture site
Monitor vitals
