GI Patho 2 Flashcards
Irritable Bowel Disease (IBD)
Incidence, prevalence, risk factors
*Canada has highest prevalence in world
Irritable Bowel Disease (IBD)
1. Crohn’s Disease
2. Ulcerative Colitis
Risk Factors
- White
- Azkenazi jewish
- South asian
- family history 10x
- Genes x environment
IBD
Etiology
*Shared etiology CD and UC = Chronic inflammatory disorder
Genes x environment
- Loss of mucosal barrier
- Loss of immune tolerance for commensal bacteria
- Dendrites (APC) present antigens to mesenteric lymph and immune system
- TH1, TH2, TH17, Treg cell differentiation and recruitment
- Pro-inflammatory cytokines IFN gamma, TNF alpha, ROS (direct damage); recruitment immune cells (macrophages, neutrophils, T cells)
Result
- Chronic inflammatory response against bowel
IBD
2 Diseases
- Crohn’s Disease
- Ulcerative Colitis
Ulcerative Colitis
Cellular pathophysiology
- starts in rectum (proctitis)
- extends continuously proximally through large intestine (pancolitis)
- chronic inflammation of mucosa layer
- starts in Crypt of Lieberkuhn
- starts on left side (rectum)
- erythema, edema (pain), mucous, ulceration, bleeding (hematchezia)
Ulcerative Colitis
Clinical Signs and Symptoms
Physical assessment
- pain mild to severe
- usually left side (rectum)
- urge to defecate
- relief of pain with defecation
- hematchezia (bloody stools)
- mucous in stools
- diarrhea (inability to absorb water > 4 per day)
- fatigue and anemia (loss of blood)
Extracolonic symptoms
- Eyes: sceleritis, uveitis
- Liver: cirrhosis
- Skin: erythema nodosum, psoriasis
- Blood: coagulation problems
- anxiety, depression
*also present in CD
Colonoscopy & biopsy
- erythema, edema, mucous, bleeding
- friability
- ulcerations
- continuous extension proximally
- infiltration WBC
Ulcerative Colitis
incidence
- 20 to 40 year olds
- smoking is protective
- diet is not associated
- NSAID use
- family history
- pathogenic gastritis
Ulcerative Colitis
Complications
- Bleeding and anemia
- ulceration
- perforation
- hemorrhage
- toxic megacolon
- fibrosis
- cancer
Non- pharmacological Management
UC
- FODMAP diet (reduced dietary fermentable oligo/di, mono and polyols)
- treatment anxiety and depression
- Screen for cancer
- maintain vaccinations
- Pharmacological induction and maintenance of remission
- medication adherence
Diagnostic Evaluation
UC
Endoscopy with biopsy (gold standard)
Crohn’s Disease
Incidnece and Risk factors
10- 30 year olds (earlier onset than UC)
- smoking 2x
- NSAIDS, antibiotic use in childhood
- reduced fibre and fat intake
- family history
- physical inactivity
- stress
Associated conditions
- asthma
- pericarditis
- psoriasis
- celiac disease
- RA
- MS
- anxiety, depression
Crohns’ Disease
Pathophysiology
- Transmural lesion
- fissures result in spasm and severe pain
- skip lesions (not continuous)
- any location mouth to anus
- most common location distal ileum, proximal cecum (ileocolitis)
- right sided pain
- malabsorption vitamins, nutrients (small intestine)
- hypoalbuminuria and macrocytic anemia
- granulomas
- string sign on barium enema (strictures)
Crohn’s Disease
Clinical Signs and Symptoms
Cardial symptoms:
- Chronic diarrhea
- abdominal pain
- fatigue
Laboratory diagnostics
- Signs of inflammation: Elevated ESR, CRP, fecal calprotectin, anti saccharomyces cerevisiae antibodies (ASCA)
Physical assessment
- Pain moderate to severe (right side usually)
- weight loss
- malabsorption and nutrient deficit (vitamin B12, folate)
- hypoalbuminuria
Stool
- +/- diarrhea
- not usually bloody
Endoscopy assessment
- skip lesions
- string sign
- granulomas “cobble stone appearance”
Extra-intestinal symptoms
- Mouth: ulcers* unique to CD
- Skin: erythema nodosum
- Liver: cirrhosis
- MSK: arthritis
- Eyes: uveitis, sceleritis
*same as UC
Crohn’s disease
Complications
- Fissures
- abscesses
- fistulas
- perforations
- obstructions
Crohn’s disease
Non-Pharmacological Management
- Correct nutritional deficiencies (vitamin B12, folate, Vitamin D, etc.)
- increase protein intake (TNF alpha and IL6 promote cachexia)
- elimination diet (food that exacerbate symptoms - high residue, nuts, citrus)
- Stop smoking
- Management stress, anxiety, depression (CBT, mindfulness)
- Medication adherence
- *limited evidence (Probiotics, omega, cannibis)
- vaccinations up to date
- screen opportunistic infections
- colorectal cancer screening
- DEXA bone density screening
- Pharmacological induction and maintenance of remission
Celiac Disease
Definition and Risk Factors
“Celiac Sprue”
Autoimmune disorder, inflammatory immune response against gluten (protein component in wheat, barley, rye, malt, spelt, kamut)
T-cell mediated auto-immune injury and destruction of SI epithelial villus
Unable to absorb vitamins, protein, fat, carbohydrate
Celiac Disease
Pathophysiology
Gluten exposure
- wheat, barley, rye, malt
T-Cell auto-immune response
- formation of antibodies
- 1. TGG IgA (transglutaminase IgA)
- 2. Anti EMA IgA (anti-endomysial antibody)
- Presence of HLA
1. HLA DQ2
2. HLA DQ8
Chronic inflammation of the SI epithelial villi
Direct destruction of the small intestine epithelial villi
- Function: increased SA and 1 cell thick, rapid absorption vitamins and macronutrients (protein, fat, carbohydrates)
- unabsorbed nutrients pull water into intestines
- water, electrolytes excreted
- osmotic diarrhea
GI endocrine dysfunction = malabsorption
- decrease GI hormone production
- decreased pancreatic endocrine/exocrine function
- decreased absorption nutrients
Celiac Disease
Clinical Signs and Symptoms
- diarrhea/constipation
- nausea/vomitting
- abdominal pain
- abdominal distention
- flatulence
- malabsorption
- weight loss
- failure to thrive
- atypical symptoms (extra-intestinal): delayed puberty, ammenorrhea, iron deficiency anemia, osteoporosis, elevated LFTs
Osmotic diarrhea +/- pain
- presence of protein, fat, carbohydrates in stool
Malnutrition, weight loss, bleeding
- Vitamin B12, folate deficiency (anemia, neuropathy, stomatitis)
- Vitamin D and calcium deficiency (secondary parathyroidism, osteoporosis)
- Vitamin K deficiency (clotting irregularities)
Skin
- Dermatitis herpetiformis (Duhring’s Disease)
Celiac Disease
Complications
Celiac Crisis
- dehydration, electrolyte abnormalities
- severe osmotic diarrhea
- hypoproteinuria
Intestinal lymphoma
Small bowel adenocarcinoma
Refractory celiac disease
- despite persistence gluten free diet for 12 months
Celiac Disease
Risk Factors
1% Western world
Type 1DM
Down Syndrome
Family history
Genetic predisposition x unknown trigger
Celiac Disease
Non-Pharmacological Management
- Gluten free diet (wheat, barley, rye, spelt, kamut)
- Nutritionist referral
- Correct nutritional deficiencies (Vitamin D, B12, copper, zinc, B6, iron, floate)
Follow Up
- monitor growth and development
- bone mineral density DEXA scanning
- lymphoma screening
Irritable Bowel Disease (IBD)
Definition
Chronic abdominal pain and altered bowel habits in the absence of organic cause/inflammation
- diarrheal IBS (men)
- constipation IBS (women)
Irritable Bowel Disease (IBD)
Risk Factors
Women > men
Diagnosed before 50s (common in 20s)
Early childhood trauma
Mood/anxiety disorders (anxiety, depresison, firbomyalgias)
Irritable Bowel Disease
Pathophysiology
Unknown
Spasms of bowel in absence of inflammation
- Viseral hypersensitivity, hyperalgesia
- post - infectious
- food allergy
- Dysbiosis of bacteria
- hypersensitivity, hypermotility, hypersecertion
Irritable Bowel Disease
Clinical Signs and Symptoms
- abdominal pain
- bloating, flatulence
- Diarrhea or constipation
- relief of pain with defecation
-* doesn’t interfere with sleep (UC does)
Rome III Criteria
- change frequency stools
- change consistency of stools
- relief of pain with defecation
- present for 6 months
- 3 symptoms / month for at least 3 months
Irritable Bowel Disease
Non-pharmacological treatment
Modification Diet:
- regular spaced meals
- decrease caffiene and alcohol
- increase soluble fibre and water intake
- bulk forming laxatives (psyillium)
- low FODMAP diet
Pharmacological treatments:
- TCA
- SSRIs
- bulk laxatives (psyllium fibre)
- loperamide
- anti-spasmotic (pepermint oil)
Diverticuli
Definition
Outpouching of the mucosal / submucosa through the artery foramen in the tunica mucular layers of the large intestine
Most common site sigmoid colon (western world, left side)
Diverticulosis
Asymptomatic disease
presence of outpouching diverticuli
no inflammation
Diverticular Disease
Definition
also known as Diverticulitis
Inflammation of the diverticlui (outpouching) resulting in clinical signs and symptoms
- LLQ pain
- WBC
- fever
Diverticulosis
Risk Factors
- older age
- obesity
- increased red meat
- NSAID use
- Low dietary fibre
- genetics
- smoking
Diverticular Disease
Pathphysiology
- increase in transluminal pressure
- increased collagen and elastin deposition in circular and longitudinal muscles
- shorten and thickening
- decrease motility (neuromuscular, low fibre)
- Outpouching of mucosa/submucosa through the foramen in the tunica layers
- Perforation and inflammation
- transition from asymptomatic diverticuli to symptomatic diverticulitis
Diverticulitis
complications
- abscesses
- bleeding
- obstruction
- perforation
- fistula
- peritonitis
Diverticulitis
Management
- do not perform sigmoidoscopy until 6-8 weeks after flare (risk of perforation)
- bowel rest
- analgesia and anti-pyretics
- higher fibre diet and water intake
- surgical resection
- *antibiotics are not usually indicated
Appendicitis
Prevalence
Most common emergency surgery for individuals 10-19 years of age
Appendicitis
Pathophysiology
- uncomplicated appendicitis
obstruction drainage of appendix (feces, foreign body, tumour) results in ischemia, inflammation
- Complicated appendicitis
Ischemia leads to abscess, necrosis, gangrene and perforation
Appendicitis
Clinical signs and symptoms
Typical
- Peri-umbilical pain
- radiation to RLQ in 24 hours
- anorexia, nausea, vomiting, fever
Atypical
- flank pain, costovertebral angle tenderness, suprapubic pain, R testicular pain, urinary frequency
Physical assessment findings:
- McBurney’s point RLQ
- Psoas sign: pain extension hip
- Oburator sign: pain right flexed hip rotation
- Rovsing Sign: pain L iliac fossa
Appendicitis
Treatment
Appendectomy
Antibiotic therapy
Intestinal Obstructions
Classification
ONSET
1. Acute: sudden onset (torsion, hernia, intussusception)
2. Chronic: slow onset (cancer)
EXTENT
1. Partial: incomplete
2. Complete: complete obstruction
LOCATION
1. Intrinsic: inside lumen (tumour, hemorrhage, edema)
2. Extrinsic: outside lumen (hernia, intussuception, fibrosis, torsion, tumour)
EFFECT
1. Simple: no impairment blood flow
2. strangulated: impaired blood flow
3. Closed loop: both distal and proximal ends
CAUSE
1. mechanical obstruction
2. functional obstruction (paralytic ileus)
Intestinal obstructions
Causes
- hernias
- tumours
- fibrosis
- torsion
- divertiulosis
- paralytic ileus (trauma, surgery, hypokalemia, peritonitis, pneumonia)
- fecal mass
- intussusception
Intestinal obstruction
Pathophysiology
Accumulation gas, intestinal contents above the obstruction -> distention
- Pneumonia
- decreased respiratory volume
- atelectasis and pneumonia
- Nausea, vomiting, dehydration, electrolyte, and acid-base imbalances
- decreased intake
- decreased absorption
- metabolic alkalosis - high obstruction, early onset
- metabolic acidosis - low obstruction, late onset
- Ischemia, peritonitis, sepsis, perforations, shock and death
- decreased venous drainage and arterial blood flow
- ischemia, necrosis
- leakage of GI bacteria -> sepsis
- necrosis of GI tissue -> perforations
- hypotensive shock
Treatment
Intestinal obstructions
- Mechanical obstruction
- surgical - Functional obstruction (paralytic ileus)
- decompression of stomach
- bowel rest
- surgical
Intussusception
Define
Proximal bowel (intussusceptum) telescopes over the distal bowel (intussuscipien)
Mesenteric vessels compressed resulting in venous distention, ischemia, and inflammation
Intussusception
Risk factors
Infants age 5-7 months
Rotavirus vaccination (2,4,6 months of age)
post operative
tumours, diverticulum, polyps, adhesions
Intussusception
Clinical Signs and Symptoms
- severe abdominal pain (colic)
- vomiting
- current jelly stools
Complications
Intussusception
Bowel necrosis
surgery within 24 hours
4/100 recurrence rate
Colorectal cancer screening
IBD
Increased risk at 30-35 years post diagnosis
Screening initiate at diagnosis and every 8 years
Mechanism: chronic inflammation
Normally progresses from low grade dysplasia -> high grade dysplasia -> cancer
