The Liver Flashcards
What are the basic functions of the liver?
Functions of the Liver
- It is the body’s main factory responsible for the synthesis and storage of amino acids, proteins (enzymes, clotting factors, etc.), vitamins, fats (including lipids and cholesterol)
- Responsible for detoxification of materials in our diet, including drugs and alcohol
- Produces bile, which not only helps digest fat, but is also a way of eliminiating waste materials (ex. bilirubin and drugs)
- It is essential in blood glucose homeostasis, including the storage of glycogen
- It is also a very important part of our innate immune system (Kupffer cells = macrophages of the liver)
Describe the metabolism of bilirubin.
Bilirubin metabolism
- Hb is broken down to heme and globin
- Heme metabolized to biliverdin and then to unconjugated bilirubin
- Unconjugated bili is transported to liver on albumin
- In the hepatocytes, bili is conjugated by UGT enzyme (making bili more water soluble)
- Conjugated bili flows down bile duct and enters duodenum
- Bacteria in colon act upon bili to form stercobilin (makes stool brown color) and urobilinogen (makes urine yellow color)
- Blockage to bile flow (ex. common bile duct stone or cancer in head of pancreas), the bile duct becomes dilated (U/S):
- Stool turns clay-coloured
- High conjugated bili = jaundice and dark tea coloured urine
- Pruritus and ALP increases
What is cholestasis?
Cholestasis = lack of bile flow
- Can occur at the level of the canaliculus or intrahepatic bile ducts (intrahepatic cholestsasis, where U/S shows no dilated ducts) or in extrahepatic bile ducts (where U/S shows dilated bile ducts)
What is the natural history of liver disease?
How do pts with liver disease present?
List the stigmata of chronic liver disease.
Stigmata of Chronic Liver Disease
- Clubbing = dilation of finger tips and loss of nail bed angle, may be seen in PBC or if hypoxic from hepatopulmonary syndrome
- Palmar erythema = redness of thenar and hypothenar eminence of palms
- Terry’s nails = increased size of white “moon” of the nail due to low albumin
- Dupuytren’s contracture = thickening of the sheath surrounding the finger flexor tendons
- Spider nevi = telangiectasia on the skin which fill from the centre
- Gynecomastia = enlargement of the breast tissue
- Altered hair distribution
- Caput medusa = enlargement of the superficial vessels in the skin of the abdominal wall around the umbilicus
- Hepatosplenomegaly
- Ascites
- Testicular atrophy
- Bruising = decreased production of clotting factors or low platelets
- Edema = swelling in tissues
Which stigmata of chronic liver disease are due to a high estrogen state?
- Palmar erythema
- Spider nevi
- Gynecomastia
- Altered hair distribution
- Testicular atrophy
What is Murphy’s sign?
Murphy’s sign
- Sign of acute cholyecystitis
- Pt will suddenly stop inspiration when the inflamed gallbladder touches the palpating hand
What testing would you complete for viral causes of elevated hepatocellular enzymes?
- Viral serology
- PCR
What test would you order if suspicious of Hereditary Hemochromatosis?
HH = Transferrin Sat >45%
What testing would you order if suspicious of Wilson’s diseease?
Wilson’s disesae = Decreased ceruloplasmin
- 24 hr urine copper study
If a patient has a decrease in alpha-1-antitrypsin wat confirmatory testing would you complete?
Phenotyping
If suspicious of Autoimmune hepatitis (AIH) what testing would you complete?
AIH
- Positive ANA +/- ASMA
- Increased IgG
- Liver biopsy
What testing do you complete if suspicious of Primary Biliary Cirrhosis (PBC)?
PBC
- AMA
- Increased IgM
What testing would you complete if suspicious of a pt with NAFLD?
NAFLD
- Glucose fasting
- Fasting lipid profile: cholesterol, triglycerides, LDL, HDL
What are the risk factors for presentation of gall stones (The 7 Fs)?
The 7 Fs
- Female = more common in women
- Fertile = 30% of pregos get sludge and 1-3% stones
- Fifty = 25% of women over 50
- Family = American Indians > Hispanics >> Caucasians
- Fat = 1/3 of obese (BMI >30)
- Fasting = rapid wt loss can result in stones
- Farmacology = ceftriaxone, octreotide