Alimentary Formative Flashcards
Which hormone is likely to be deficient as a result of gastrectomy?
Gastrin
Excess production of which hormone will result in normal gastric mucosal appearances but delayed gastric emptying?
CCK
Function of CCK
Facilitates digestion within the small intestine
Secreted from mucosal epithelial cells in the duodenum
Stimulates delivery into the small intestine of digestive enzymes from I cells of the pancreas
Relaxes sphincter of Oddi to increase delivery of bile from the gallbladder to the duodenum
Function of bile
Contains bile acids for digestion of fats in the small intestine
Fat soluble vitamins
A, D, E, K
What mechanism is responsible for maintaining a low gastric pH?
H/K ATP pumps
What is the inactive form of digestive tract enzymes?
Zymogen
Which of the following digestive processes is most important to promote digestion of fats? A Conjugation B Emulsification C Enterohepatic circulation D Glycolysis E Phosphorylation
B Emulsification
A 23 year old male with a history of alcohol misuse presented with acute upper abdominal pain and vomiting. He was found to have a raised serum amylase.
What is the most likely diagnosis?
Acute pancreatitis
What is the normal defaecation mechanism?
Stretch receptors in the rectal wall activate parasympathetic centers in the spinal cord
A 50 year old man presented to the Emergency Department complaining of a three month history of epigastric pain and a two day history of a very high volume of vomiting.
What is the most likely anatomic site of bowel obstruction to cause this symptom?
3rd part of the duodenum
A 45 year old woman has surgical removal of her distal ileum to treat inflammatory bowel disease.
Which vitamin is she at risk of becoming deficient in?
B12
Where is intrinsic factor produced?
Parietal cells of the stomach
What is the function of intrinsic factor?
Absorption of vitamin B12 in the terminal ileum
A 24 year old man has an inherited defect and is unable to produce intrinsic factor.
The absorption of which substance is most likely to be impaired?
Vitamin B12
A 55 year old man presents with a six week history of progressive painless jaundice and weight loss. On inspection, he is jaundiced. Abdominal palpation is normal.
What is the most likely diagnosis?
Pancreatic cancer
A 30 year old man presents with jaundice. He has been complaining of intermittent right hypochondrial pain and nausea for several months, but the pain has worsened, his urine is darker than usual and his stools pale.
Which imaging test is most appropriate in the first instance?
Abdominal USS
A 45 year old man is stabbed in the lower chest. The knife cuts most of the vagus nerve fibres around the oesophagus. He makes a good recovery.
What is most likely to occur as a result of this nerve injury?
Delayed gastric emptying
A 40 year old man has a total colectomy to treat a colonic carcinoma. The operation is curative.
What is a likely side effect of this operation?
Hyponatraemia
A 70 year old woman presents with jaundice. She has been complaining of right abdominal pain and altered bowel habit for several months. On examination she has a hard craggy mass in her right iliac fossa and hepatomegaly. An abdominal ultrasound is performed.
Which one of the following is the most likely finding in the liver at ultrasound?
Multiple liver metastases
A 70 year old man presented with abdominal pain, vomiting and abdominal distension. He reported absolute constipation. An abdominal radiograph shows multiple dilated loops of bowel.
Which of the following bowel findings on abdominal x-ray would be in keeping with small bowel obstruction?
Central distribution of loops of bowel
A 45 year old smoker presents with massive haematemesis and melaena. Endoscopy reveals an actively bleeding posterior ulcer in the first part of the duodenum.
Which artery is most likely to be bleeding?
Gastro-duodenal artery
Which ingredients would be required to make a suitable ORT solution to combat dehydration caused by intestinal fluid loss?
NaCl and glucose
A patient underwent a cholecystectomy for treatment of chronic cholecystitis. During the operation, the surgeon noticed arterial blood loss from the gall bladder neck.
Which artery is most likely to have been injured?
Cystic artery
A 50 year old patient undergoes surgical removal of the gastric antrum as a curative operation for gastric cancer. This reduces his gastric acid production.
How does the surgical procedure reduce acid production?
Decreases gastrin production
Function of gastrin
Stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and aids in gastric motility
A 25 year old woman presents with a six week history of diarrhoea, and oral aphthous ulcers. Her stool contains blood and mucus.
What is the most likely diagnosis?
Crohn’s disease
What is the funtion of a PPI
Proton pump inhibitor reduces gastric acid production
A 25 year old man presents with fever, bloody diarrhoea and cramping for several weeks that does not resolve with antibiotic therapy. Proctosigmoidoscopy reveals red, raw mucosa and faecal calprotectin is 800 g/µg stool (normal range is 0-50).
What is the most likely cause?
Ulcerative colitis
What does a high faecal calprotectin indicate?
Released into the intestines in excess when there is any inflammation, can indicate a person has IBD
A 20 year old man presents with a twelve hour history of colicky periumbilical pain, which shifts to the right iliac fossa, fever and loss of appetite.
What is the most likely diagnosis?
Acute appendicitis
A 45 year old man was admitted to hospital after ingesting 25 g of paracetamol three days earlier. He had no past medical history of note, took no regular medication and rarely consumed alcohol.
Which of the following signs would be consistent with his presentation?
Jaundice
Maltose hydrolysis
Glucose + glucose
Sucrose hydrolysis
Glucose + fructose
Lactose hydrolysis
Glucose + galactose
A 71 year old man had a malignant tumour of the middle third of the oesophagus.
What is the most likely histopathological diagnosis?
Squamous carcinoma
What is the function of secretin?
Increased production of bicarbonate from pancreas and hepatic duct cells
Decreased gastric acid production
How is acid build up in duodenum reduced?
Inhibition of gastric acid secretion
Reduced gastric emptying
What is the function of pepsinogen?
An inactive zymogen
Secreted into gastric juice from mucous cells and chief cells
Activated by stomach acid into the active protease pepsin, which is largely responsible for the stomach’s ability to initiate digestion of proteins
What are enterogastrones? (function)
Any hormone secreted by the mucosa of the duodenum in the lower gastrointestinal tract in response to dietary lipids that inhibits the caudal (or “forward, analward”) motion of the contents of chyme
What are enterogastrones? (hormones)
Secretin
CCK
GIP
GIP function
Gastric inhibitory polypeptide
Induces insulin secretion
Where is gastric mucus produced?
Surface epithelial and mucous neck cells
Complications of gallstones
Acute inflammation of gall bladder Carcinoma of gall bladder Jaundice Biliary colic Pancreatitis
Why does jaundice affect the clotting system?
Absence of bile in small bowel
Failure of absorption of fat soluble vitamins including vitamin K
Haematemesis differential diagnosis
Gastritis Peptic Ulcer Gastric carcinoma Oesophageal varices Oesophageal carcinoma
Development of gastric cancer
Normal Chronic gastritis Intestinal metaplasia Dysplasia Carcinoma
Routes of gastric cancer spread
Direct spread
Lymphatic spread
Blood spread
Transcoelomic spread
Which bacterium is associated with the development of gastric cancer?
Helicobacter pylori
How is H. pylori eradicated from the stomach?
Triple therapy - two antibiotics + a PPI
Complications of peptic ulceration
Perforation
Bleeding
Stricture formation
What is the cause of coeliac disease?
Sensitivity to gluten
What procedure provides the diagnosis and what is the characteristic histological finding of coeliac disease?
Small bowel/duodenal biopsy
Villous atrophy
What skin condition is associated with coeliac disease?
Dermatitis herpetiformis
What is the commonest treatment for coeliac disease?
Exclude gluten from diet
Causes of high serum amylase
Pancreatitis Tumours (pancreatic/salivary glands)
