Lecture 5: Disorders of the SI/Colon Flashcards
SI anatomy image review
What are the 3 phases of digestion?
- Intraluminal: dietary fats, proteins, carbs are hydrolyzed and solubilized by pancreatic and biliary enzymes
- Mucosal: brush border enzymes hydrolyze peptides and saccharides
- Absorptive
What is celiac disease?
Abnormal IMMUNE response to gluten/gliadin.
Permanent disorder.
Who is at highest risk for celiac disease?
Caucasians
What happens to the SI in celiac disease?
Atrophy of the SI villa and malabsorption of nutrients.
Antibody production will occur as well.
How does classic celiac disease present?
- Diarrhea, steatorrhea, flatulence
- Dyspepsia
- Wt loss
- Abd distension
- Weakness, muscle wasting
- Growth retardation in children
- Resolution of symptoms upon not eating gluten food.
What skin findings are seen in celiac disease?
Dermatitis Herpetiformis (pruitic, papulovesicular rash)
If this is present, good chance they have celiac.
What serology test is the initial workup for celiac disease?
IgA TT antibody test
Extremely sensitive and specific.
Pt should make NO diet changes prior to this test!
What are the secondary serologic antibody tests we might order for celiac disease?
- Total IgA
- IgA anti-endomysial antibody
- IgG DGP
What is the standard way of diagnosing celiac disease with a positive serologic test?
Endoscopic mucosal biopsy of both the proximal and distal duodenum.
Should show blunting or loss of intestinal villi.
What might endoscopy show on imaging for celiac disease?
- Atrophy of duodenal folds
- Nodular, scalloping of duodenal folds, fissuring, mosaic pattern
What causes whipple disease?
- Tropheryma whipplei
- G+, non-acid fast, PAS positive bacillus
- Fecal-oral transmission
How does whipple disease typically present?
- Arthralgias (MC symptom reported first)
- Diarrhea
- Abd pain
- Wt loss (MC SYMPTOM OVERALL)
What PE findings are seen in whipple disease?
- Low-grade fever
- Evidence of malabsorption
- Enlarged joints
- LAN
What is the whipple disease mnemonic?
- Weight loss
- Hyperpigmentation of skin
- Infection with tropheryma whipplei
- PAS positive granules in macrophage
- Polyarthritis
- LAN
- Enteric involvement
- Steatorhhea
WHIPPLES
How do you diagnose whipple disease?
EGD with biopsy of duodenum showing macrophages with PAS bacilli/granules
PCR can confirm if inconclusive
How do you treat whipple disease?
- IV rocephin or meropenem
- Followed by Bactrim for 1 year
What is bacterial overgrowth?
- Colonic bacteria seen in excess in SI.
- Proximal short bowel normally has a small amt of bacteria.
What are the causes of bacterial overgrowth?
- Motility disorders
- Anatomic disorders (adhesions)
- Diabetes
- Immune disorders
What are the common symptoms of small intestinal bacterial overgrowth? (SIBO)
- Nausea
- Bloating
- Gas
- Abd pain
- Fatigue
- Cramps
- Acne rashes
- Wt loss
How do we confirm SIBO?
- Small intestine aspiration w/ cultures (highly invasive)
- Carbohydrate breath test with lactulose and carb cessation
How do you treat SIBO?
- Ciprofloxacin 500mg BID
- Augmentin
- Bactrim
7-10 days
Also, correct anatomic defect if present (like adhesions)
What causes short bowel syndrome? (SBS)
- Removal of a portion of the SI
- Crohn’s, ischemia, tumor, trauma, mesenteric infarction, or volvulus
How does a terminal ileal resection present?
Malabsorption of B12 and bile salts
How does an extensive bowel resection present?
- > 50% of SI removed
- Wt loss and diarrhea d/t malabsorption
How do you manage the initial/acute phase of SBS?
- Manage fluids/lytes
- Acid suppression with PPIs
- Parenteral nutrition
How do you manage the adaptation phase of SBS?
- Transition to oral feedings
- Complex carbs
- Low fat
- Fluids, PPIs, antidiarrheals, and ABX for SIBO
What is lactase?
Brush border enzyme that hydrolyzes lactose.
How is lactose intolerance confirmed?
Hydrogen breath test with 50g of lactose.
Must fast 8 hours prior.
What is paralytic ileus?
Neurogenic failure or loss of peristalsis in the SI without any mechanical obstruction.
Who is paralytic ileus MC in?
Hospitalized patients:
- Intra-abdominal processes such as recent GI or abd surgery
- Peritoneal irritation
- Severe medical illness
- Meds like opioids or anticholinergics
Post surgery, what is the order in which the GI system recovers?
- SI motility normalizes
- Stomach
- Colon
What occurs that causes paralytic ileus?
- Inflammatory response to intestinal manipulation and trauma
- Inhibitory neural reflexes increase sympathetic activity in the gut
- Opioids inhibit motility
How does paralytic ileus present?
- N/V/obstipation, abd discomfort
- Abd distension w/ tympany to percussion
- Diminished/absent bowel sounds
- Diffuse abd pain
How do we workup and diagnose paralytic ileus?
- Clinical dx if > 4 days
- Plain films should show distended/dilated gas-filled loops
- CT to distinguish between ileus and SBO.
What labs help r/o other causes of paralytic ileus?
- CBC: r/o infection, ischemia, abscess
- CMP: hypoK can worsen ileus
- BUN/Cr: Uremia can cause ileus
- LFTs, amylase, lipase: gallbladder/pancreatitis can cause ileus
How do we treat paralytic ileus?
- Complete bowel rest via IV fluids and NG tube
- Slowly advance diet
- Activity
- Remove any offending drugs
What preventative methods can aid with ileus?
- Avoid IV opioids
- Early ambulation
- Clear liquid diet
- GUM CHEWING (stimulates vagus nerve)
What is a small bowel obstruction? (SBO)
- Impairment of the normal flow of intraluminal contents
- Mechanical obstruction
What does a full SBO do? Partial?
- Partial is only lumen
- Full w/ strangulation will impair blood supply and cause necrosis
What secondary conditions can occur due to SBO?
- SIBO
- Distension
- Hypovolemia
- Dilation of intestines
- Feculent emesis
- Peritonitis (if no strangulation)
Everything getting clogged up
If SBO is prolonged, what could occur blood-flow wise?
- Reduced perfusion
- Tissue ischemia
- Necrosis and perforation
What is the MCC of SBO?
Post-surgical adhesions
70%
What are the S/S of SBO?
- Acute
- Nausea/vomiting
- Colicky abd pain
- Obstipation (severe/complete constipation)
- Proximal blockage: profuse emesis with undigested food
- Diffuse blockage: Diffuse and poorly localized cramps with feculent vomiting
- High-pitched tinkling sound
- Fever
What is a hallmark sign of SBO?
Dehydration, which leads to tachycardia and hypotension
When are you more likely to hear hyperactive bowel sounds in SBO?
Early on, as the GI system attempts to overcome the block.
Hypoactive comes later as it gives up.
What are the signs that suggest intestinal ischemia?
- Fever > 100F
- Tachycardia
- Peritoneal signs: guarding, rigid abdomen, rebound tenderness, disproportionate pain
How do we confirm a SBO?
Plain XRAYs of the abdomen showing dilated small bowel loops with air-fluid levels and a “ladder-like” appearance.
How do we treat SBO?
- Admit and consult surgery
- Fluid/lytes
- NG tube
- TPN
- ABX for bowel compromise
Ileus vs SBO chart
What is Ogilvie syndrome?
Acute colon pseudo-obstruction
Spontaneous massive dilatation of the cecum and proximal colon in the absence of an anatomic lesion
Who is ogilvie syndrome MC in?
Severly ill, hospitalized patients (post-op is MC)
Most likely due to impaired autonomic response.
What are the S/S of ogilvie syndrome?
- Severely distended abdomen
- Abd tenderness with guarding or rebound tenderness
- Peritonitis will occur if perforation has occurred
- Bowel sounds either normal or decreased
How do we workup ogilvie syndrome?
- Plain radiographs showing dilated colon, esp at the cecum to splenic flexure
- CT can help establish and r/o other causes
How do we treat ogilvie syndrome initially?
- Conservative treatment
- NG and rectal tube for colonic decompression
- Rolling patient side to side in fetal position
- NPO, IV fluids
- Neostigmine for severe
Who is conservative treatment indicated in for ogilvie?
- Little to no abd tenderness
- No fever
- No leukocytosis
- Cecal diameter < 12cm
What does neostigmine do?
Inhibits destruction of ACh, allowing impulses to move in the intestine.
What are the essentials of diagnosing ogilvie syndrome?
- Severe abd distension
- Post-op or severely ill
- Precipitated by lytes or meds
- Absent to minimal abd pain; minimal tenderness
- Massive dilation of cecum or right colon
What is the primary cause of IBS?
Idiopathic
What chronic GI symptoms typically result in IBS?
- Abnormal motility
- Visceral hypersensitivity
- Enteric infection
- Psychosocial
Who is IBS MC in?
Young women
What are the 4 pathogenesis things that result in IBS?
- Abnormal motility
- Visceral hypersensitivity
- Intestinal inflammation
- Psychosocial abnormalities
How does IBS typically present?
- Abd pain related to at least 2/3: defecation, stool frequency change, stool form change
- Crampy, lower abd pain that relieves with defecation
- 3 months of symptoms
- Abd pain that DOES NOT OCCUR AT NIGHT (usually)
- Abd distension, bloating
- Dyspepsia, heartburn, fatigue
What are the 4 IBS classifications?
- IBS with diarrhea
- IBS with constipation
- IBS with mixed constipation and diarrhea
- IBS that is not subtyped
What is the Rome IV criteria for IBS?
Recurrent abd pain that averages out to at least 1 day a week in the past 3 months and is related to defecation, change in stool frequency, or change in stool form
2/3 must be present
What is the manning criteria for IBS?
Higher likelihood with more symptoms
What alarm symptoms suggest that a person is NOT having IBS?
- Severe progressive pain
- Pain associated with anorexia or wt loss
- Severe constipation
- Severe diarrhea
- Hematochezia/rectal bleeding
- Wt loss
- Fever
When is a colonoscopy indicated for IBS evaluation?
Anyone over 50 or ones that fail conservative treatment.
How do we manage IBS?
- Low FODMAP diet
- Avoid alcohol, caffeine
- Avoid fats, spicy, gas-producing foods
- Relax
- Therapy
- Exercise
What is FODMAP?
- Fermentable
- Oligosaccharides
- Disaccharides
- Monosaccharides
- And
- Polyols
What are the drugs that may help with IBS?
Adjunctive therapy
- Antispasmodics (Dicyclomine or hyoscyamine)
- Loperamide
- Laxatives (osmotics)
- Specific IBS drugs (Linaclotide, lubiprostone, alosetron)
- TCAs
- SSRIs
For IBS w/ diarrhea, what specifically might help the most in terms of meds?
- Antispasmodics (Dicyclomine, hyoscyamine)
When is alosetron used?
- IBS w/ diarrhea in women
- Diarrhea > 6 months
What is alosetron?
5-HT3 receptor antagonist
Same class as ondansetron
What is the BBW of alosetron?
- Severe constipation
- Ischemic colitis
Patients must sign consent prior to use
What is linaclotide used for?
IBS w/ constipation
Clo = Con
What is linaclotide?
Guanylate cyclase agonist
What are the pros of linaclotide and the BBW?
Pros: stimulates intestinal fluid secretion and transit.
BBW: DO NOT USE IN CHILDREN < 18y + Risk of dehydration
Also pricey af
lubes ur insides
What is lubiprostone used for?
- IBS w/ constipation in women
- Chronic constipation
Both IBS constipation drugs have an I in their name, like constipation.
They also both start with L and lube up ur insides for constipation
What is lubiprostone and its CIs?
- Selective chloride activator that activates channels, increasing fluid secretion and motility and reduces permeability.
- CIs: Diarrhea, GI obstruction
also pricey af
lubes up ur SI
What are antidepressants used for in terms of IBS subtype?
IBS w/ pain and bloating or diarrhea.
TCAs
What is the bad kind of ABX associated colitis?
C Diff
How do you kill C diff?
Handwash with soap.
Sanitizers DO NOT WORK.
What abx usually cause abx associated colitis?
- Ampicillin
- Clindamycin
- 3rd gen cephalosporins
- FQs
How does mild-mod ABX associated colitis present?
- Greenish, foul-smelling, watery diarrhea 5-15 times a day
- LLQ tenderness
- WBC > 15k
How does severe/fulminant abx associated colitis present?
- Fever
- Hemodynamic instability
- Abd pain, distension, tenderness
- Profuse diarrhea (up to 30/day)
- WBC > 30k
What are the concerning complications of abx associated colitis?
- Dehydration
- Wt loss
- Hemodynamic instability
- Toxic megacolon
What 3 things may suggest C. diff colitis?
- Recent ABX use
- Hospitalization
- Advanced age
When should we suspect C diff Colitis?
> = 3 loose stools in 24 hours
How do we workup abx associated colitis?
- Positive NAAT
- Positive stool test
How do we treat abx associated colitis?
- D/c current abx
- Contact precautions
- Mild-mod: Fidaxomicin BID or Vanco 125mg PO QID
- Severe: Vanco 500mg PO QID + Metronidazole IV
10d, fidaxomicin has lower recurrency
Severe would be WBC > 15k
Remember vanco must be ORAL for colitis
When is surgery indicated for CDI?
C Diff infection
What are the two surgeries for CDI?
- Total abdominal colectomy (For bad cases)
- Diverting loop ileostomy/colonic lavage (decreased risk)
If CDI recurs once, what do we do?
Same regimen again or prolonged vanco tapering regimen.
If CDI recurs twice, what do we do?
7 week tapering regimen of vanco
- QID for 14 days
- BID for 7 days
- QD for 7 days
- QOD for 7 days
- Q3d for 14 days
14-7-7-7-14
What is ischemic colitis?
Reduction in blood flow that commonly occurs at watershed areas like the splenic flexure or rectosigmoid junction.
What are the 3 arteries that supply the colon?
- Superior mesenteric
- Inferior mesenteric
- Internal iliacs
Who is ischemic colitis MC in?
- Older
- Atherosclerosis
- Post-op
- Cocaine
- Extreme exercise
What are the risk factors for ischemic colitis?
- Any condition that lower perfusion to the intestine
- Any condition that predisposes someone to mesenteric arterial embolism, thrombosis, or vasoconstriction
What 4 things can cause colon ischemia in younger patients?
- Vasculitis
- Coag disorders
- Estrogen
- Long-distance running
How does ischemic colitis typically present?
- Rapid onset of mild, cramping abd pain
- Tenderness over affected area (left side usually)
- Diarrhea with hematochezia
- Urgent desire to defecate
- Mild-mod rectal bleeding
How is acute ischemic colitis typically described as?
Abd pain out of proportion to the physical exam.
How does chronic mesenteric ischemia typically present?
- Recurrent abd pain after eating due to inability to increase abd perfusion to help digest.
- Patients will often develop food fears and lose weight.
What is the 1st imaging modality for ischemic colitis?
- CT abd w/ con
- Target/thumbprinting/double halo sign
- Reflects initial episode of ischemia and the subsequent reperfusion injury.
What should everyone suspected of ischemic colitis get in terms of diagnostics?
Diagnostic colonoscopy
How do you treat ischemic colitis?
Supportive care and NPO status
When is surgical intervention recommended for ischemic colitis?
- Ongoing pain
- Persistent fever
- Leukocytosis
- Peritoneal irritation
- GI bleeding
What etiology would prompt us to use anticoags for ischemic colitis?
Mesenteric venous thrombosis
What is the MC congenital abnormality of the small bowel?
Meckel’s diverticulum
Often found incidentally
What is the rule of 2s for Meckel’s?
- Present in 2% of the population
- 2ft from ileocecal valve
- Symptomatic in 2% of patients
How does Meckel’s diverticulum present?
- Crampy abd pain
- N/V
- Bleeding
What is Meckel’s sign?
Ectopic gastric mucosa on nuclear medicine scan
How do you treat Meckel’s?
Surgery is definitive.
What is diverticulOSIS?
- Outpouching of the colon.
- MC in sigmoid/left colon
What causes diverticulosis?
- Chronic constipation
- Low fiber
- Hard stools
Increased intraluminal pressure
What are the 3 forms of diverticulosis?
- Uncomplicated
- Diverticulitis
- Bleeding diverticula
How does uncomplicated diverticulosis present?
- Asymptomatic usually
- Abd pain, chronic constipation
- Mild LLQ tenderness, palpable sigmoid colon
- Normal labs
How do you treat uncomplicated diverticulosis?
High fiber diet
How does diverticulitis present?
- ACUTE LLQ abd pain
- Low grade fever
- Bowel changes
- N/V
- Bloody stool
- LLQ tenderness
- Mild-mod leukocytosis
Diverticulitis means infection of the outpouchings
What is the 1st line imaging for diverticulitis?
CT of abd to check 1st time or if its complicated.
When is colonoscopy recommended for diverticulitis?
Anyone that responds to acute mangement should get one 4-8 weeks later.
Do not due initially due to risk of perf.
For mild-mod symptoms of diverticulitis, what is the general OP tx?
Clear liquid diet and then high fiber after resolution
For immunocompromised patients, what ABX might we use for diverticulitis?
- Metro + quinolone
- Metro + Bactrim
- Augmentin
7-10
For more complicated and IP tx of diverticulitis, what is the tx?
- NPO with IV fluids
- Piptazo IV followed by Cipro + metro PO
- Surgery for severe disease or lack of improvement after 72 hours.
When is hospitalization recommended for diverticulitis?
- Increasing pain, fever, or PO intolerance
- Immunocompromised
- Significant comorbidities
- Abscesses > 3-4cm
- Signs of severe diverticulitis (high fever, leukocytosis, peritoneal signs)
What is the criteria for inpatient treatment of diverticulitis?
- Complicated CT with perf
- Sepsis
- Immunosuppression
- High fever > 102.5F
- Severe abd pain
- Age > 70
- Significant comorbidities
- PO intolerance
- Failed OP tx
- Noncompliant
AKA really sick or really old
What is the MCC of a lower GI bleed?
Diverticular bleed
Treated with colonoscopic cauterization or waiting.
