WEEK 10: Gastrointestinal Health Flashcards
What does “motility” refer to?
Motility refers to contraction and relaxation of walls and sphincters of gastrointestinal tract to move (propel) content.
Gastric motility is regulated by what types of contractions?
gastric motility is regulated by a combination of tonic and phasic (also called rhythmic) contractions.
What is the purpose of gastrointestinal motility?
Gastrointestinal motility serves to fragment and mix food boluses for digestion and absorption along with propelling contents along the tract.
In what way are phasic contractions physiologically different from tonic contractions?
phasic contractions are characterised by periods of relaxation and contraction, rather than being sustained.
T or F
Tonic contractions are sustained contractions that are maintained for several minutes to hours.
T
Where anatomically are tonic contractions typically observed?
These are usually observed at the sphincters separating the different parts of the gastrointestinal tract.
All tonic contractions happen subconsciously except for…
the sphincters that control defecation
Defecation centres in the …. allow for conscious input when defecating.
lumbro-sacral spinal cord
Phasic contractions occur through … signaling generated by interstitial cells of Cajal in the enteric nervous system.
autonomic
Phasic contractions occur through autonomic signaling generated by …. in the enteric nervous system.
interstitial cells of Cajal
Phasic contractions occur through autonomic signaling generated by interstitial cells of Cajal in the …. system.
enteric nervous
Constipation is clinically defined as…
small/infrequent/difficult bowel movements
T or F
Constipation can have a variety of causes.
T
Occasional bouts of constipation can be caused by…
dehydration, a lack of fibre or a particular drug regimen.
Chronic constipation is defined as having fewer than … bowel movements per week.
3
T or F
Neurological problems can cause chronic constipation.
T
Specifically, neurological problems that affect the nerves that control the colon and rectum.
What type of patients could you expect to have chronic constipation caused by neurological problems?
Patients with a spinal cord injury, a previous stroke, diabetes, multiple sclerosis, Parkinson’s disease, and dementia are at higher risk of chronic constipation.
What is anismus?
A type of pelvic floor dysfunction where patients are unable to relax their pelvic muscles.
What is dyssynergic defecation?
A disorder caused by physical problems with the muscles involved in defecation such as defects in the coordination of relaxation and contraction.
What type of patients could you expect to have chronic constipation caused by physical problems?
Patients with blockages in the colon or rectum such as bowel obstructions, rectal cancer or another abdominal cancer that puts pressure on the colon.
T or F
Conditions leading to dehydration such as chronic hyperglycaemia as a result of diabetes and thyroid imbalances, can cause chronic constipation.
T
What are the four different types of interventions that are frequently used to try and provide symptomatic relief of chronic constipation? (that don’t involve drugs passing into circulation)
Stool softeners,
osmotics,
stimulants, and
bulk-forming agents.
Chronic diarrhoea is defined as having at least …/… of stools being loose or watery for a period of … months or more.
one quarter
3
Acute diarrhoea is typically associated with ….
viral or bacterial infections or the effects of a course of antibiotics.
How can diarrhoea kill someone?
Through dehydration
What are the indications of serious dehydration in adults?
No urination or low urination with dark-colour, dry skin & mouth, excessive thirst, fatigue, weakness, confusion and/or disorientation
What are the indications of serious dehydration in young children and infants?
No or low urination (in infants not having a wet nappy for 3 or more hours), dry skin, mouth and tongue. Fever above 39*, no tears when crying, drowsiness, lack of response, or grumpiness, Sunken eyes, cheeks, or abdomen
T or F
Chronic diarrhoea is almost always a symptom of another underlying condition.
T
What conditions could chronic diarrhoea be a sign of?
IBS or IBD condition, such as Crohn’s or Ulcerative Colitis.
In children and infants, … species are the most common cause of acute diarrhoea.
Rotavirus
In the general Australian population, … is the most common cause of acute diarrhoea with an estimated 1.8 million infections per year.
norovirus
What viruses may produce acute diarrhoea?
Rotavirus, norovirus, enteric adenovirus, astrovirus, viral hepatitis and cytomegalovirus
What two bacteria are most commonly the cause of travellers diarrhoea?
E. coli and C. coli
What is dysbiosis?
An imbalance between the types of organism present in a person’s natural microflora, especially that of the gut.
Antibiotics can lead to … resulting in diarrhoea.
dysbiosis
Why can artificial sweeteners cause diarrhoea?
because they are neither absorbed nor digested and are osmotically active, drawing water into the gastrointestinal tract, particularly the colon resulting in loose stools.
Why can lactose cause diarrhoea in those without lactase in their gut microbiota?
Undigested lactose is osmotically active, causing osmotic diarrhoea and can also be used by certain types of gut flora which have a propensity to promote diarrhoea
Surgery involving partial resection of the intestine can sometimes cause diarrhoea due to changes in …
nutrient absorption
Why can gallbladder removal cause diarrhoea?
gallbladder removal, which results in a large decrease in bile acid delivery to the gastrointestinal tract reduces fat absorption, which can result in diarrhoea.
T or F
Irritable bowel syndrome and irritable bowel disease are interchangeable terms.
F
IBS is functional gastrointestinal disorder and is thus defined by a series of symptoms (rather than a specific cause)
IBD is a category of gastrointestinal disorders such as Crohn’s disease and ulcerative colitis
IBS is defined as recurrent … pain on average at least …day/week in the last … months, associated with … or more of the following Rome IV criteria:
…
…
…
abdominal, 1, 3, 2
Related to defecation
Associated with a change in frequency of stool
Associated with a change in form (appearance) of stool
IBS classified into at least … different types.
4
How many types of stool are recognised in the bristol stool scale?
7
What stool types in the bristol stool scale are considered abnormal?
1, 2, 6 and 7
What is IBS subtype C?
IBS with predominant constipation
In order to be classified as having IBS subtype C patients must have greater than …% of bowel movements with Bristol stool types … or … and less than …% of bowel movements with Bristol stool types … or …
25%, 1 or 2, 25%, 6 or 7
What is IBS subtype D?
IBS with predominant diarrhea.
What is IBS subtype M?
IBS with mixed bowel habits
What is IBS subtype U?
Unclassified
In order to be classified as having IBS subtype D patients must have … than 25% of bowel movements with Bristol stool types … or … and … than 25% of bowel movements with Bristol stool types … or …
greater, 6 or 7, less, 1 or 2
In order to be classified as having IBS subtype M patients must have … than 25% of bowel movements with Bristol stool types 1 or 2 and … than 25%% of bowel movements with Bristol stool types 6 or 7.
greater, greater
T or F
Since the cause(s) of IBS are unknown, all treatment is focussed on symptomatic relief.
T
The first line of treatment for IBS is…
lifestyle modification.
T or F
Triggers for IBS are generally thought to be causative.
F!
T or F
There is some evidence that people with IBS-D who are not coeliac may benefit from reducing gluten.
T
T or F
All current treatments for Crohn’s Disease are targeted at altering immune system function.
T
T or F
IBS has a strong autoimmune component
F
The causes of IBS are unknown. IBD has a strong autoimmune component.
What does NAFLD stand for?
Non-alcoholic Fatty Liver Disease
What does NASH stand for?
Non-alcoholic Steatohepatitis
Non-alcoholic fatty liver disease (NAFLD) can progress to what?
Non-alcoholic steatohepatitis (NASH)
…. is the most common alcoholic liver disease or alcoholic hepatitis.
Drug induced liver disease
T or F
The outcomes for Drug induced liver disease are the same as for NASH.
T
The consumption of which drug is most commonly associated with drug induced liver disease?
paracetamol
…. is the most frequent cause of acute liver failure in Western countries.
Drug-induced liver disease
The most common symptom of drug induced liver injury is…
jaundice
T or F
Most cases of drug-induced liver injury are accompanied by debilitating symptoms.
F
Most cases of DILI are asymptomatic.
T or F
Dili is more common in men than women.
F
DILI is more common in women
T or F
A liver biopsy is required for the diagnosis of DILI
F
Do clinical presentations of hepatocellular (cytotoxic) injury have a predictable or idiosyncratic mechanism of hepatotoxicity?
Predictable
Do clinical presentations of cholestatic injury have a predictable or idiosyncratic mechanism of hepatotoxicity?
idiosyncratic
If a patient has Hepatocellular (cytotoxic) injury, their histologic findings will show…
hepatitis
If a patient has Cholestatic injury, their histologic findings will show…
Cholestasis
If a patient has mixed DILI, their histologic findings will show…
Steatosis
What is Steatosis?
Fatty liver.
What is Cholestasis?
the slowing or stalling of bile flow from your liver.
What is Hepatitis?
Inflammation of the liver tissue.
