Functional Intestinal Disorders Flashcards
Functional Intestinal Disorders (definition)
A group of disorders characterized by chronic GI symptoms in the absence of demonstrable pathology on conventional testing
Common symptoms of functional GI disorders (FGID)
- Constipation
- Diarrhea
- Dyspepsia
- Low abdominal pain
- Dysphagia
- Bloating
Most common functional GI disorders seen in family medicine (4)
- Irritable bowel syndrome
- Functional dyspepsia
- Infant colic
- Infant regurgitation
Functional GI disorders are due to…
dysfunction of the brain-gut axis
What is the brain-gut axis?
It is a bi-directional communication network between the brain CNS and gut ENS, influenced by a variety of environmental, genetic and biopsychosocial factors.
Consequence of multifactorial pathophysiology in functional GI disorders
This contributes to visceral hypersensitivity in FGIDs
Visceral hypersensitivity: Why is a hypersensitive gut “chaotic”?
- Due to the release of inflammatory mediators like cytokines and histamine when the gut is presented with a pathogen or food peptide (can damage the gut, make enteric nerves more sensitive or dysmotile)
- Due to altered gut microbiome (post-infection)
- Due to primary anxiety and depression, which can make visceral afferent fibres in the gut more sensitive, triggering inflammation
Which comes first in FIGDs?
a) psychological distress
b) GI symptoms
50/50
In some cases, psychological distress triggers GI symptoms, while in others gut dysfunction occurs first.
In either case, psychological distress is an is an integral part of the disease process and should be addressed as both a contributing factor and treatment target.
The pathophysiology of FGIDs can vary a lot - why is it important to understand it?
Explain with the following scenarios:
a) Dietary antigens triggering inflammation
b) Altered gut microbiome
c) Primary anxiety related to trauma
d) Elevated inflammatory markers and primary inflammatory cascade
Multiple underlying causes can guide multiple therapeutic possibilities.
a) Dietary antigens triggering inflammation: Dietary modification
b) Altered gut microbiome: Specific, targeted antimicrobial treatment (e.g. H. pylori eradication)
c) Primary anxiety related to trauma: Psychotherapy
d) Elevated inflammatory markers: Targeted anti-inflammatory or immunotherapy
What types of patients have poorer outcomes in terms of their functional gastrointestinal disorders? Why?
Patients who have experienced depression/anxiety or trauma in childhood (esp. sexual abuse).
This is because these conditions can fundamentally alter secretion of important neurotransmitters (serotonin, norepinephrine) or dysregulate the hypothalamic-pituitary-adrenal axis.
Most common FGID.
Irritable bowel syndrome
Irritable bowel syndrome (definition)
A disorder to the GI tract characterized by abdominal pain and altered bowel habits.
IBS is more common in:
a) men
b) women
b) women
What comorbidities are often associated with IBS?
- Chronic conditions: fibromyalgia, migraines
- Anxiety/depression
Diagnostic criteria for IBS
Recurrent abdominal pain at least one day per week in the last 3 months, associated with two of the following:
* related to defecation
* associated with a change in frequency of stool
* associated with a change in form (appearance) of stool
Criteria must be fulfilled for at least 3 months, with onset of symptoms at least 6 months prior to diagnosis!
Differential diagnosis for IBS (4)
- Crohn’s disease
- Ulcerative colitis
- Celiac disease
- Colorectal cancer (CRC)
You must rule out these conditions before diagnosing IBS or FGID!
Specific questions that should be addressed when investigating IBS during history
- Recent GI infections?
- Family history of IBD, celiac disease or CRC?
- Changes in weight?
- Any evidence of bleeding?
- Medication history?
- Is there a relationship between symptoms and psychosocial distress?
Red flags (IBS): MEMORIZE
- Age of onset after 50 years
- Rectal bleeding, melena (black stool)
- Nocturnal diarrhea
- Progressive worsening of abdominal pain
- Unexplained weight loss
- Family history of IBD or colorectal cancer
On top of negative red flags, what should be NORMAL for a patient with IBS/FGID?
Bloodwork/lab results!
True or false: Patients with IBS do not typically have any red flags on history, nor do they have abnormalities in their laboratory examinations
TRUE
When are advanced imaging tools or endoscopic tools indicating when suspecting an FGID diagnosis?
They are rarely indicated since patients with IBS do NOT have any red flags on history nor any abnormalities in their laboratory examinations.
In the presence of red flags on history, what investigations should you consider?
- Abdominal ultrasound
- Abdominal C scan
- Colonoscopy
How do we manage IBS (FGIDs)
Establish a therapeutic alliance (multiple point of care visits, help the patient understand the bio-psychosocial underpinning of their condition, give them tools to improve quality of life).
IBS is a chronic condition!
Lifestyle and stress reduction advice for managing IBS (FGIDs)
- Improving sleeping patterns
- Reducing caffeine and alcohol intake (have negative effects on GI and sleep)
- Exercise (20-60 minutes 3x per week)
- Stress relief strategies (Headspace, NERVA)
- Identification and management of psychopathology
- Cognitive behavioural therapy
- Pharmacotherapy
Pharmacotherapy: Name medications for constipation, diarrhea
Constipation: polyethylene glycol
Diarrhea: loperamide
SSRIs should NOT be first line therapy, may have GI side effects!
ARFID (definition)
Avoidant restrictive food intake disorder: A newly emerged category of eating disorders that may develop secondary to IBS, as avoidant trigger foods can become severe and lead to food phobias.
Dietary management of FGIDs
Assess and optimize diet as part of the initial management strategy. Educate the patients what to eat and how to eat.
Many patients with IBS have poor diet quality and diversity, as well as irregular dietary patterns
Evidence-based diet recommendation for IBS patients
Low-FODMAP diet, i.e. a diet low in short-chain carbohydrates that are poorly absorbed, ferment rapidly and can cause bloating and pain.
Examples of low-FODMAP foods
- Fruits
- Broccoli, cabbage, carrots, kale, cucumber, tomato
- Oats, rice, corn, quinoa
- Nuts
- Beef, chicken, pork, fish, eggs
- Plant-based milks, butter, cheese, cottage cheese
- Sugar, stevia
Examples of high FODMAP foods (to avoid in IBS)
- Garlic, onions, mushrooms, avocado, asparagus, peas, cauliflower
- Wheat, rye, barley, bran
- Cashews, pistachios
- Processed meats
- Cow and goat milk, fatty cheese
- Honey, agave
Other than low-FODMAP, other dietary recommendations for IBS?
- Avoid gas-producing foods
- Avoid insoluble fibre, and promote soluble fibre (can improve constipation and diarrhea)
No scientific evidence to support the use of … for IBS
- Use of probiotics
- Strict elimination of gluten (unless the patients notice that it is a contributing factor to their IBS)
- Nonspecific food allergy testing
Ask patients where they are getting their information and recommendations
