Formative exam Flashcards
A 43 year old woman present to her GP with upper abdominal pain that sometimes radiates to her right shoulder tip. The pain comes on about an hour after a meal, is constant and makes her feel sick. The pain subsides after about an hour. The GP thinks that this lady might have gallstones.
What is the pain associated with gallstones called?
biliary pain
when gallstones get stuck in the cystic duct the gall bladder has to release bile
this causes pain as the contract is against a blocked stone
biliary colic = pain that doesn’t go away between contractions
true colic= should disappear between contractions
Why does the pain associated with gallstones typically come on
about an hour after food (make reference to CCK release)? (3x 1 marks)
1) takes an hour or so for ingested material to be released by the stomach to duodenum
2) CONTAINS ACID, AMINO ACIDS AND FATTY ACIDS stimulated released of CCK from I cells
3) CCK causes gallbladder contraction
4) pain due to contracting against blockage
Several weeks later the lady returns to the GP with worsening abdominal pain and a fever. The pain is more constant and longer lasting than previous episodes. Her right upper quadrant is now tender to palpate.
What do you think has now occurred in this patient? (4x 1⁄2 marks)
- gallstone is now probably lodged in the cystic duct and is causing cholecystitis
- wall of the gallbladder are inflamed and oedematous and secondary infection can occur due to bacterial proliferation
If a gallstone moves out of the gallbladder it can become lodged in the common bile duct (CBD).
State the potential complications of a stone lodging in: (i) Proximal CBD (2x marks)
(ii) Distal CBD (2x marks)
i)
- cholangitis (infection of biliary tree
- post hepatic jaundice (hyperbiluruminemia)
ii) acute pancreatitis - stone lodging near the sphincter of oddi can block major pancreatic duct. this can damage the pancreatic acinar cells due to an increased back pressure- auto digestion
- post hepatic jaundice
- steatorrhea (fat in poo) –> malabsorption due to reduced release of lipase and protease from pancreas (could also cause diarrhea due to increase osmolaritt int the lumen)
Following chronic alcohol intake the liver can enlarge (hepatomegaly).
(i) Name the underlying change that has caused liver enlargement (1x mark)
(ii) briefly describe two mechanisms that lead to the process you have named in (i) (2x marks)
i) steatosis- fatty liver
ii) a byproduct of alcohol metabolisms is NADH which inhibits lipid breakdown (and/or promotes lipid synthesis)
iii) ethanol inhibits formation and secretion of lipoproteins
Briefly describe two reasons why chronic alcohol misuse can lead to malnutrition and vitamin deficiencies (2x marks)
- chronic gastritis- inflammation prevents malabsorption
- pancreatitis (impaired release of digestive enzymes)
- intestinal mucosal damage (impaired absorption/ digestion)
- intake of alcohol replacing calories diet
- vitamin deficiency- liver is a key site of storage of vitamins e.g. copper and ion and glycogen (cirrhotic liver not happy)
The Lady undergoes an emergency endoscopy which visualises oesophageal varices which are an example of a porto-systemic anastomosis.
Briefly explain the most likely processes that have led to the formation of oesophageal varices in this lady (4x 1 marks)
- chronic alcohol misuses has eld to cirrhosis (fibrotic changes in liver)
- cirrhosis has led to portal hypertension
- portal hypertension has created a back pressure on veins draining through liver, including oesophageal veins
- oesophageal veisn form the portal section of the porto-systemic anastomosis in the oesophagus responsible for varices
State two other areas of the body where porto-systemic anastomoses exist (2x 1⁄2 marks)
umbilical region
anal canal
bare area of liver
retroperitoneum
A 25 year old female presents to her GP with a 5 week history of passing loose non bloody stools, weight loss and abdominal pain.
The GP performs a physical examination on the lady and elicits abdominal tenderness in the right lower quadrant and visualises some perianal pathology. The GP suspects inflammatory bowel disease and organises a colonoscopy. The results from the colonoscopy indicate the presence of Crohn’s disease.
Describe two features of Crohn’s disease that could be visualised during a colonoscopy? (2x marks)
- skip lesions
- cobblestone appareance
- hyperaemia (red) and oedema of mucosa (inflammation)
- strictures
- openings of fistulae
(transmural and varying thickness of epithelium- need biospy for this not just a colonoscopy)
During the colonoscopy a biopsy of the gut mucosa is performed
What microscopic finding is pathognomonic (very characteristic) of Crohn’s disease? (1x mark)
epitheliod granulomas
Describe three perianal pathologies that might be present in Crohn’s disease (3x marks)
anal fissures haemorrhoids skin tags perianal abscess opening of a fistula
Explain why the right lower quadrant is a common site for abdominal pain and tenderness in Crohn’s disease? (2x marks)
most common site of involvement in crohns disease is the ileo-caecal region - terminal ileoitis
this is found in the right lower quadrant
Explain why weight loss can occur in Crohn’s disease (2x marks)
typically affects small intestine- site of nutrient absorption
inflammation can reduce absorption over time
decreased water weight due to diarrhea
inflammation uses lots of energy- burns calories
You are attending a general medical clinic as a student and the consultant askes you a series of questions based on a patient who presents with jaundice.
Briefly describe where bilirubin originates from (1x mark)
bilirubin ir released when RBC are destroyed buy the reticuloendothelial system in the spleen
Briefly describe the role the livers plays in processing and excreting
bilirubin (2x 1 mark)
liver conjugates bilirubin with glucuronic acid to make it soluble then excretes bilirubin as a component of bile
In pre-hepatic jaundice the raised plasma bilirubin levels tend to be unconjugated despite normal liver function.
Briefly explain why (3x marks)
- pre-hepatic jaundice is caused by conditions which shorten the lifespan or increases breakdown of RBC (haemaglobinopathies- spherocytosis and ellipticyotis)
- this increases the levels of bilirubin reaching the liver beyond its ability to conjugate and process bilirubin
- resulting hyperbilirubinaemia is therefore mostly unconjugated
in post hepatic jaundice patients will often notice they have dark urine
Explain why this occurs (6 x 1⁄2 marks)
- in post-hepatic juandice the liver is abvle to process that conjugates bilirubin- bilirubin is soluble
- however there is a blockage of flow of bile into the gut so plasma (conjugated) bilirubin rises
- as the bilirubin is soluble is can be excreted by the kidneys and bilirubin gives the urine a dark colour
(pale pooo- lack of bilirubin going to GI)
In post-hepatic jaundice conjugated bilirubin levels are raised.
What other liver function test (LFT) when raised is indicative of post-hepatic jaundice? (1x mark)
ALkaline phosphatase (ALP) - biliary tract damage
underlying change that causes liver enlargement
fatty liver
fistula
abnormal connection
fistula
abnormal connection
where is a stomach ulcer most likely to be found
lesser curve of the stomach
if a gastric ulcer were to erode through the posterior aspect of the body of the stomach, which major artery might be at risk from haemorrhoge
splenic artery
a lady suffering from long term alcoholism goes for a checkup from her GP. She has a number of blood samples taken including her liver function tests. What blood test result when raised would specifically indicate hepatocyte damage
alanine transaminase (ALT)
what blood test when raised would reliably indicate that a gallstone is stuck in the common bile duct
conjugated bilirubin levels
ALT
specific to hepatocytes
AST
raised in liver damage bnut also present in cardiac and skeletal muscle so not specific to liver
ALP
raised in biliary obstruction and bone disease - conjugated bilirubin better measure
which transporter moves glucose across the basolateral membrane of the enterocyte
GLUT2
GLUT5
moves fructose CROSS THE APICAL MEMBRANE OF THE ENTEROCYTE
SGLT-1
sodium glucose linked transporter that co-transports Na and glucose from the gut into the enterocyte
mass movcemebt
rapid movement of colonic content
visceral afferent nerve responsible for relaying epigastric pain
greater splanchnic
through which anatomical site does the indirect hernia leave the abdomen
deep inguinal ring
which pancreatic protease once activated, is itself a catalyst for the activation of other pro-enzymes
trypsin
