6. Jaundice Flashcards

1
Q

F Which of the following statements is false?

  1. The liver lies in the right hypochondrium.
  2. The hepatic blood supply is 35-40% of the cardiac output.
  3. The portal vein supplies 75% of hepatic blood flow.
  4. The liver is divided into 8 segments.
  5. The acinus is the functional hepatic unit.
A

The hepatic blood supply is 35-40% of the cardiac output – it is actually 25%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

F Which of the following statements is true?

  1. The sympathetic nervous system releases acetylcholine causing the gallbladder to contract.
  2. Cholecystokinin is released in response to the presence of carbohydrates in the gut.
  3. Cholecystokinin is released in response to the presence of amino acids in the gut.
  4. The gallbladder synthesises 50 mls of bile per day.
  5. The entero-pancreatic reflex is mediated by the sympathetic system.
A

Answer: Cholecystokinin is released in response to the presence of amino acids in the gut.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

F Obstructive jaundice is commonly caused by gall stones within what structure?

  1. Pancreas.
  2. Cystic duct.
  3. Gallbladder.
  4. Right hepatic duct.
  5. Common bile duct.
A

Answer: Common bile duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

F What structure is situated within the duodenal loop?

  1. Pancreas.
  2. Cystic duct.
  3. Gallbladder.
  4. Right hepatic duct.
  5. Common bile duct.
A

Pancreas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

F Microsomal enzyme uridine diphosphoglucoronosyl transferase (glucuronyl transferase) catalyses the formation of what?

  1. Free bilirubin.
  2. Conjugated bilirubin.
  3. Unconjugated bilirubin.
  4. Stercobilinogen.
  5. Urobilinogen.
A

Answer: Conjugated bilirubin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

F Bacterial enzyme hydrolysis in the gut produces this compound which is excreted in faeces:

  1. Free bilirubin.
  2. Conjugated bilirubin.
  3. Unconjugated bilirubin.
  4. Stercobilinogen.
  5. Urobilinogen
A

Answer: Stercobilinogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

F Which compound is returned to the liver by the enterohepatic circulation?

  1. Free bilirubin.
  2. Conjugated bilirubin.
  3. Unconjugated bilirubin.
  4. Stercobilinogen.
  5. Urobilinogen.
A

Urobilinogen. But unconjugated bilirubin is also returned in a lesser extent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

F Concerning the function of the pancreas, which of the following is false?

  1. Glucagon is secreted by the alpha (A) islet cells.
  2. Insulin is secreted by the beta (B) islet cells.
  3. Somatostatin is secreted by the gamma (G) islet cells.
  4. Glucagon stimulates the breakdown of glycogen.
  5. Pancreatic polypeptide is secreted by the F islet cell.
A

Answer: Somatostatin is secreted by the gamma (G) islet cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

F What is the central structure in a hepatic lobule?

  1. Portal vein.
  2. Hepatic artery.
  3. Bile duct.
  4. Tributary of the hepatic vein.
  5. Portal triad.
A

Answer: Tributary of the hepatic vein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

F Which one of these cells is part of the reticuloendothelial system in the liver?

  1. Hepatocyte.
  2. Sinusoidal endothelial cell.
  3. Kupffer cell.
  4. Fibroblast.
  5. Ito cell.
A

Answer: Kupffer cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

F Which of the following causes an increased serum unconjugated (free) bilirubin and increased faecal urobilinogen?

  1. Pre-hepatic cause of jaundice.
  2. Hepatocellular cause of jaundice.
  3. Post-hepatic (obstructive) cause of jaundice.
  4. Mixed picture cause of jaundice.
  5. None of the above.
A

Answer: Pre-hepatic cause of jaundice. There is too much for the entero-bacteria to process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

F What is the cause of physiological jaundice of the newborn?

  1. Excess breakdown of foetal haemoglobin.
  2. Immaturity of conjugation enzyme mechanisms in the liver.
  3. Diversion of portal blood flow into the umbilical vein.
  4. Horizontal alignment of the common bile duct as it enters the duodenum.
A

Answer: Excess breakdown of foetal haemoglobin. However, this is related to immaturity of conjugation enzyme mechanisms in the liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

F Which of these is NOT a cause of obstructive jaundice?

  1. Cirrhosis.
  2. Hepatitis.
  3. Pancreatic carcinoma.
  4. Gall stones.
  5. Gilbert’s syndrome.
A

Answer: Gilbert’s syndrome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

F Which of these is NOT a function of the liver?

  1. Glycogen storage.
  2. Storing vitamins A, D, E, and K.
  3. Production of cholesterol.
  4. Production of urobilinogen.
  5. Conversion of thyroxine (T4) into triiodothyronine (T3).
A

Answer: Production of urobilinogen – this is done by gut bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

O Describe the anatomy of the liver and bile ducts and the microscopic anatomy of the
hepatobiliary system

A

Within the porta hepatis D A V From anterior to posterior
Functional unit of the liver (liver lobules):
- Central vein - Drained into by the portal vein and hepatic artery - All the central veins converge into 3 hepatic veins - These then open directly into the anterior surface of the IVC - In the other direction you will have bile ducts draining into canaliculi, which then drain into the common bile duct - Space of Disse between the sinusoids is where bilirubin is released from albumin. It then enters the hepatocyte to be conjugated
Within the Calot’s triangle = Lunds node Borders = cystic duct, cystic artery, common bile duct
This impression is from the hepatic flexure of the

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Within the Calot’s triangle = …=

A

Lunds node Borders = cystic duct, cystic artery, common bile duct

17
Q

O Describe the haemoglobin and bilirubin metabolism-including excretion!!!!

A

RBCs engulfed by a macrophage (mainly in spleen and liver)
2. Haemoglobin is broken down into haem and globin
3. Globin part is recycled
4. Haem is broken down into porphyrin ring and an iron ion (Structure of Haem – porphyrin
(carbon ring) plus iron)
5. The porphyrin ring is then broken down into biliverdin by haem oxygenASE
6. Biliverdin is then broken down into bilirubin by biliverdin reductase
7. Biliverdin is green, bilirubin is yellow
8. Bilirubin binds to albumin to travel to the liver
9. Albumin bound to albumin diffuses across the fenestrated sinusoid membrane into the space of Disse
10. In the space of Disse, albumin releases bilirubin
11. Bilirubin enters the hepatocyte via a bilirubin transporter (facilitated diffusion)
12. Once inside the hepatocyte, it’s joined to glucaronic acid by UDP glucaronyl transferase to
become conjugated bilirubin
13. Now that bilirubin is conjugated, it travels in the canaliculi to the right or left hepatic duct.
These then join to form the common hepatic duct and then drain into the gallbladder via the cystic duct.
14. When a fatty meal has been eaten, CCK-Cholecystokinin causes release of bile (with conjugated bilirubin) from
the gallbladder into the duodenum (enters via the ampulla of Vater). CCK also causes relaxation of the sphincter of Oddi to allow this to happen.
15. In the small intestine – bilirubin can be broken down into urobilinogen
16. Urobilinogen can either continue into the large intestine where it becomes stercobilinogen
which is then acted upon by colonic bacteria to form stercobilin (colours the faeces) – this happens to the majority of it (90%)
17. Or it can be reabsorbed (10%) and travel back to the liver (portal venous system) and then
travel to the kidneys, where it’s oxidised to urobilin to colour the urine – (5%)
18. The remaining 5% goes back into the duodenum by the bile duct (enterohepatic circulation)

18
Q
Colours
Biliverdin
Conjugated bilirubin
Urobilin 
Stercobilin
A

= green
= yellow
= yellow
= brown

19
Q

O Describe the anatomical areas of the abdomen

A

Structures in the Transpyloric plane (L1) – join the tips of the 9th costal cartilages
1. Hilum of the right kidney
2. Fundus of the gallbladder
3. Pyloric sphincter
4. End of spinal cord (conus medullaris) (in babies the spinal cord ends between L3 and L4 so
you cant do a lumbar puncture on a baby)
5. DJ flexure
6. Head and neck of the pancreas
Subcostal plane – horizontal plane and L3 joining the lowest part of the costal margin at the 10th costal cartilages. Origin of the IMA and 3rd part of the duodenum.
Coeliac trunk – T12
SMA – just below coeliac trunk around T12
Renal arteries – junction between L1 and L2
Gonadal arteries – L2
IMA – L3
Bifurcation of aorta - L4

20
Q

O Appendix is located…

A

McBurney’s point is the name given to the point over the right side of the abdomen that is one-third of the distance from the anterior superior iliac spine to the umbilicus (navel). This point roughly corresponds to the most common location of the base of the appendix where it is attached to the cecum

21
Q

Transpyloric plane has … on it

A

gall bladder, pancreas, pylorus of the stomach and duodeno-jejunal flexure all lie on this plane.

22
Q

O. Focused history from a jaundiced patient to elicit a possible cause

A
  • Bowel habits (the colour of their stool)
  • Itchy skin (due to deposition of bile salts) – pruritis
  • Weight loss (to rule out cancer)
  • Have they been drinking, smoking or taking drugs
  • Referred pain (spleen pain if it was splenomegaly)
  • More pain after a big meal? (gallbladder)
23
Q

Definition of jaundice

A

= a yellowing of the skin, mucosa, and sclera of the eyes due to an increased level of bilirubin in the blood.

24
Q

Describe the classification of the causes of jaundice

A

Pre hepatic and hepatic

25
Q

Describe the classification of the jaundice A

A

Usually caused by haemolytic diseases (sickle cell, haemolytic anaemia, malaria, beta thalassemia)
Increased total bilirubin in blood
Increased unconjugated bilirubin (because you’ve exceeded the amount the liver can conjugated)
Normal faeces
Liver function tests will also be normal
Splenomegaly present (haemolysis)
Normal urine colour – because unconjugated bilirubin is insoluble in water and is bound to albumin which is not filtered by the kidneys, so is not excreted in urine. Therefore you will not see a change in urine colour or urine level of unconjugated bilirubin. In haemolytic diseases, the unconjugated bilirubin will go through the same process as normal in the liver, resulting in higher urine levels of urobilinogen.

26
Q

Describe the classification of the jaundice B

A

The problem is with the liver itself (either that it cannot take up, conjugate or excrete the bilirubin) – cirrhosis, alcoholic liver disease, drugs, liver cancer, neonatal jaundice (when you haven’t yet developed all the enzymes needed for conjugation)
Decreased urine urobilinogen (as liver isn’t converting it), dark urine due to raised conjugated bilirubin, either normal or pale faeces, ALT and AST elevated as they leak out of the liver when the liver is diseased.
Splenomegaly present because the spleen is compensating/trying to help the liver break down RBCs
In the blood – all levels of bilirubin increase:
Unconjugated – because the liver can’t conjugate effectively
Conjugated – because the liver is “leaky”

27
Q

Describe the classification of the jaundice C

A

Obstructive – gallstones blocking either the cystic or common bile duct, cancer (pancreatic, gallbladder)
High conjugated bilirubin only, because the liver is working fine.
AST and ALT are normal (no problem with the liver, the problem occurs after), and no splenomegaly for the same reason
“colicky pain”
Pale faeces – because it’s not getting into the intestines and bowel
Increased urine urobilinogen – hepatic system still working
Increased urine bilirubin – could be either hepatic or post-hepatic
You will NEVER get unconjugated bilirubin in the urine because it’s BOUND TO ALBUMIN which is not filtered by the kidneys (due to globulin).