Gastrointestinal Flashcards
Name the sections of the small and large intestines in order.
duodenum jejunum ileum Caecum Appendix Colon
Name the neurones/plexus found in the following:
mucosa
submucosa
muscularis externa
mucosa- enteric neurones
submucosa- submucous plexus
muscularis externa- myenteric plexus
From which cells does excitation originate in the circular and longitudinal smooth muscle of the gut? Name the waves that are produced
Interstitial cells of Cajal
Slow waves
With ______ _______ contraction in the gut, the longer the excitation exceeds the threshold for an action potential, the greater the strength of __________.
smooth muscle
contraction
Which three types of neurones are located in the enteric nervous system apart from autonomic nerves.
Sensory
Interneurones
motor
Name the six main sphincters of the alimentary canal.
Upper and lower oesophageal
pyloric
ileocaecal
internal and external anal
Name the two tissues in which glycogen is stored in the body.
Liver
muscle
when does glycogenesis, glycogenolysis and glucogenesis occur
glycogenesis- during/after meals
glycogenolysis- in between meals
glucogenesis- overnight/fasting
Name the main enzyme involved in glygogenesis and glycogenolysis
glycogenesis- glycogen synthase
glycogenolysis- glycogen phosphorylase
Insulin causes an increase in _______ ________ and a decrease in ________ ________. Glucagon has the opposite effect.
glycogen synthase
glycogen phosphorylase
Which four vitamins are stored transported in lipids
Vitamins A D E K
Name the compound that facilitates long chain fatty acid transport into the mitochondria.
Carnitine
Name the histological feature that is characteristic of the following: duodenum, jejunum, ileum
Duodenum- Brunners glands- secrete alkaline liquid to neutralise chyme
Jejunum- plicae terminalis- folds covered in villi
Ileum- Peyer’s patches- GALT
What is the longitudinal muscle of the large intestines called?
teniae coli
What does the portal triad consist of?
hepatic artery, hepatic portal vein, Bile duct
The central vein at the centre of each hepatocyte is a venule of what vein?
the hepatic vein
What cells line the bile ducts?
Cholangiocytes
Through what channels does blood flow to the central vein of the hepatocyte? What is the space beside these channels called?
sinusoids perisinusoidal space (space of Disse)
What do you call the resident macrophages of the liver?
Kupffer cells
What is bilirubin and how is it produced?
A brown pigment produced by the breakdown of red blood cells in the spleen
How is bile transported to the bile ducts in the hepatocytes of the liver?
through bile cannaliculi
In what way is the bile modified in the gall bladder?
It is made more concentrated. Na+ and Cl- ions are actively transported into out of the bladder setting up an osmotic gradient which the water within the lumen follows.
What are zymogens?
Precursors of enzymes
What effect does histamine, gastrin and acetylcholine have on the gastric secretion of H+ ions.
Increase H+ secretion
How do you calculate BMI?
BMI=mass/height2
What area of the brain mediates body mass?
Hypothalmus
What is Ghrelin and by which cells is it produced?
A hunger signal molecule produced by the Oxyntic cells of the gastric mucosa
_______ and ______ are ________ signals. They increase in concentration in the blood when more fat is stored.
Leptin
insulin
adiposity
peptide YY and Glucagon-like peptide 1 _______ gastric emptying and food intake
decrease
The Orad stomach exhibits _____ contraction while the caudad stomach exhibits ______ contraction.
tonic
phasic
What do you call the peristaltic contraction/relaxation of the caudad stomach?
Antral pump
What cells are found in 1.Pyloric glands and 2. oxyntic glands
- D cells (somatostatin) G cells (Gastrin)
2. Parietal glands (HCL) Chief cells (enzymes)
What effect does Somatostatin have on gastric HCL secretion?
Decreases it
What is the migrating motor complex?
strong peristaltic contractions that slowly pass the length of the intestine
Polysaccharides are catabolised to _____________ by __________ within the lumen. They are subsequently broken down to monosaccharides by ______________ integrated with the membrane.
Oligosaccharides e.g. sucrose, maltose, Lactose
Alpha-amylase- breaks down 1,4 glycosidic bonds
oligosaccharidases
Intrinsic factor is needed for the absorption of what vitamin?
Vitamin B12
Name a proton pump inhibitor
Omeprazole, Iansoprazole
Name a Histamine (H2) receptor antagonist
Ranitidine
Name an anti-muscarinic drug.
Buscopan
Name an anti-diarrhoeal drug
Loperamide
Name two Aminosalicylates. they are the firstline treatment of what disease?
Sulfalazine, Mesalazine
Ulcerative colitis
Name a Dopamine receptor antagonist.
Domperidone, metaclopramide
Ondansetron is an example of what drug?
A 5-HT3 receptor antagonist
Name an immunosuppressive drug used in the treatment of UC and CD
Azathioprine
Name two Anti-TNF therapy drugs used to treat UC and CD
Infliximab
adalimumab
What clinical sign is caused by an excess of bilirubin in the blood?
Jaundice
The liver has __ segments and __ lobes. name the anatomical lobes.
8
4
right lobe, left lobe, quadrate lobe, caudate lobe
The IVC and Hepatic veins have no ______. Back pressure on the liver causes __________. this can occur as a result of heart failure
valves
hepatomegaly
What leukocyte cell is found between roughly every 10 enterocytes?
Intraepithelial lymphocytes
Apart from intraepithelial lymphocytes, what other immune cells are found in the mucosa?
Dendritic cells
After _________, T cells within the gut mucosa migrate to the __________ lymph nodes and then enter the bloodstream and return in numbers to the intestines. T cells bind to ____________ on the capillary endothelium of the lamina propria then they bind to _________ and initiate ________.
activation mesenteric MAdCAMs enterocytes necrosis
The ratio of different immunoglobulins in the intestines is the opposite of that in the gut. list the three main immunoglobulins from greatest abundance to least.
IgA:IgM:IgG
The gut is said to be ___________ to accommodate for the commensal bacteria.
Hyporesponsive
Patients with Coeliac disease possess intraepithelial T-cells which are specific to ______ _________. These cells proliferate and destroy epithelial cells leading to _____ _______ and ___________of the small intestines
Gamma Interferon
Villus atrophy
Scalloping
Vomiting is mediated by the ______ centre of the brainstem. emetic stimulus is mainly sensed in the ________ _______ ______.
emetic
Chemoreceptor trigger zone
Name three types of antagonists which are used as anti-emetic drugs.
dopamine receptor
muscarinic receptor
H2 receptor
5-HT3
The combination of circular muscle and longitudinal muscle contraction in the large intestine creates bulges called ________.
Haustra
The cells of the colon are known as _________ which are responsible for __, ___ and ____ absorption the colonic crypts are responsible for __ and _____ secretion.
Na+ Cl- H20 K+ HCO3-
Name four important proteins that are synthesised in the liver.
albumin
complement proteins
apoproteins
Define diarrhoea.
Loss of 500ml of fluid and solutes in one day from the GI tract.
State three dangerous effects of diarrhoea.
dehydration, hypokalaemia, metabolic acidosis (HCO3- loss)
State three causes of diarrhoea.
hypermotility, impaired NaCl absorption, poorly absorbable solutes.
The protrusion of the sphincter of Oddi into the duodenum is known as the ________________.
hepatopancreatic ampulla
ampulla of Vater
ERCP is used to investigate what vessels?
Those associated with the pancreas and gall bladder
Jaundice occurs when the _____ ___ is blocked because the _________ returns to the liver and then into the __________.
bile duct
bilirubin
bloodstream
Reflux Oesophagitis causes superficial squamous epithelial damage leading to_________. If this continues, _______ oesophagus may ensue. Metaplasia occurs and the stratified squamous epithelium transitions to ________ epithelium. This appears _____ macroscopically. If the disease progresses there is a risk of developing ____________ where the metaplasia becomes dysplasia.
hyperplasia Barrett's Columnar red adenocarcinoma
State the three causes of chronic gastritis
Bacterial- H. Pylori infection
Autoimmune-antibodies to parietal cells
Chemical- NSAIDS, Alcohol, bile reflux
How do H. Pylori cause Chronic gastritis?
They occupy an ecological niche between the mucus and epithelial cells. They damage these cells leading to reduced mucus production, therefore the wall is exposed to the gastric acid and pepsin leading to peptic ulceration.
As well as causing Chronic gastritis, H. Pylori is also a risk factor for ___________ and __________.
Adenocarcinoma
lymphoma
Acute ischaemia of the small bowel is classified by the degree of infarction. Identify the effect of mucosal, mural and transmural infarction.
MUCOSAL- resolution
MURAL- fibrosis–stricture–chronic ischaemia–obstruction
TRANSMURAL- gangrene–perforation–peritonitis–sepsis
What causes Meckel’s diverticulum?
Incomplete regression of the vitello-intestinal duct
What does GORD stand for? name three possible causes of this condition
Gastro-Oesophageal Reflux Disease
raised intra-abdominal pressure
dysfunctional LOS
abnormal oesophagus motility
What is gastroparesis?
delayed gastric emptying
Dyspepsia is associated with what condition?
Peptic ulcer disease
Identify three hallmarks of oral malignancy
red and white patches, bleeding, ulceration
What is melaena and what is haematemesis?
Melaena- black faeces discoloured by digested blood
Haematemesis- vomiting up fresh blood
Where is Crohn’s disease most common in the body?
ileum and colon
CD presents with __________ lesions throughout the GI tract. They cause deep ________ within the mucosa which cause a macroscopic ____________ pattern. It exhibits _________ inflammation and non-caseating __________.
skip fissures cobblestoning transmural granulomas
UC presents with __________ lesions and is restricted to the _______ and _______ in the GI tract. It exhibits ________ and _________ inflammation. Inflammatory cell influx destroys the mucosa, and the tissue left forms _________.
continuous rectum colon mural mucosal pseudopolyps
What is the MUST score used for?
Score determining level of malnutrition.
Refeeding Syndrome can occur after prolonged starvation. What electrolyte shifts occur as a result of this condition?
hypokalaemia
hypophosphataemia
hypomagnesaemia
McBurney’s point marks the position of what part of the bowel?
appendix
What symptoms characterise Appendicitis?
Central abdominal pain radiating to the right iliac fossa
Name one potentially fatal complication of appendicitis
peritonitis
In most cases appendicitis is treated by ___________ _______________. However, if an appendix mass is present it is treated with _________ and __ ____________.
Laparoscopic appendectomy
analgesics
antibiotics
Repeated/major small bowel resection can cause ____- _______ _________.
Small Bowel syndrome
The sigmoid colon possesses a mesentery called the ________ _________. This allows a significant amount of movement which may lead to a _______ ________.
Sigmoid Volvulus
What is the name of the premalignant precursor to adenocarcinoma?
Adenoma
Define Diverticula
A mucosal herniation through the muscle coat. diverticulosis is the presence of diverticulum
How do you treat uncomplicated Diverticulitis?
Oral antibiotics
What virus commonly causes diarrhoea and vomiting in young children?
Rotavirus
What virus is known as the winter vomiting bug?
Noravirus
What is the main bacterial cause of gastroenteritis? How is it mainly spread?
Campylobacter
What is the main cause of bacterial gastroenteritis? How is it mainly spread?
Campylobacter
faecal-oral spread
What bacteria causes Dysentery? Identify the characteristic symptom of dysentery.
Shigella
Diarrhoea with blood and mucus
In addition to the external anal sphincter, name a skeletal muscle that acts as a sphincter of the rectum
Puborectalis
The Truelove and Witt criteria are used to assess the severity of what condition?
Ulcerative Colitis
The Rome III criteria is used for the diagnosis of irritable bowel syndrome. Identify what this criteria states
Patient experiences abdominal pain three times a month associated with 2/3 of the following:
improves with defaecation
change in stool frequency
change in stool appearance
Identify the three types of IBS
IBS-D diarrhoea
IBS-C constipation
IBS-M mixed
What dietary advice is given to IBS patients?
High soluble fibre diet
Low FODMAPS
Name two anti-diarrhoeal drugs
Loperamide, imodium
Laxido and movicol are examples of what type of drug?
Osmotic laxatives
Name two anti-spasmodics used in the treatment of IBS.
colofac, colpermin
What is Anorexia Nervosa?
Psychiatric condition- Self-induced weight loss due to an overvalued idea- fear of fatness
What is Bulimia Nervosa?
Psychiatric condition- failure to restrict eating leading to binges
Name a characteristic symptom of Right sided colorectal cancer
Unexplained Iron deficient anaemia
Identify three investigations of colorectal cancer
Barium enema
colonoscopy
sigmoidoscopy
Identify three symptoms of bowel obstruction
abdominal distension- due to trapped swallowed air
colicky abdominal pain
constipation
Jaundice is classified by the site of origin- identify the three types
pre-hepatic, hepatic, post-hepatic
________ is the endpoint of liver disease where bands of ___________ separate the hepatocyte nodules.
Cirrhosis
fibrosis
Portal hypertension is a complication of liver disease. Identify the signs that this creates.
Oesophageal varices
medusa
ascites
haemorrhoids
Pathology of Alcoholic liver disease:
alcohol induces ____ _________ appearance in the liver. Continued alcohol use results in hepatitis which exhibits _________ inflammation, _________ bodies and fibrosis. Fatty liver and hepatitis are reversible but fibrosis and cirrhosis are not.
Fat vacuoles
neutrophilic
Mallory bodies
What is Haemochromatosis
Excess of Iron in the liver
Identify the four stages of NAFLD
steatosis- steatohepatitis- fibrosis- cirrrhosis
identify the intermediate in alcohol metabolism between ethanol and acetate
Acetaldehyde
Name the site of an inguinal hernia
Hesselbach’s triangle
identify some of the main symptoms of Cholestasis
Biliary colic
-RUQ pain radiates to shoulder
jaundice
What acid is used in the treatment of cholestasis?
Ursodeoxychloric acid
What is acute cholecystitis and how is it treated?
Inflammation of the gall bladder because the bile duct is blocked by a gallstone. treated by urgent cholecystectomy
Acute pancreatitis is caused by obstruction of the _______ _________ ______. The proteases and lipases within the organ become activated meaning autodigestion occurs
Common bile duct
What is the best investigation for cholestasis and pancreatitis?
Ultrasound scan
What type of colitis is caused by C. difficile infection
Pseudomembranous colitis
What is Rovsing’s sign?
pressing the LIF causes pain in the RIF
Most appendix are found in which position?
Retrocaecal
Hyperamylasaemia is a sign of disease in which organ?
Pancreas
What is the most common cause of pernicious anaemia?
Loss of the parietal cells which produce intrinsic factor for vitamin B12 absorption
Identify three tests for H. pylori
Serological tests-IgG antibodies
C-Urea breath tests
CLO- biopsy urease test
Under 55s with H. Pylori peptic ulceration can move straight to __________ therapy meanwhile elderly patients require an __________.
Eradication
endoscopy
What characterises stools of cholera patients?
Rice water stools
