Disorders of the SI & Colon - Exam 3 Flashcards
The small intestine begins at _____ and ends at the ______
pylorus of the stomach and ends at the ileocecal junction
What are the 3 phases of digestion?
intraluminal
mucosal
absorptive
phases of normal digestion: _______ dietary fats, proteins, carbs are hydrolyzed and solubilized by pancreatic and biliary secretions
intraluminal
phases of digestion: _________ requires sufficient surface area of intact small intestinal epithelium
__________ are important in the hydrolysis of disaccharides and di-and tripeptides.
Malabsorption of specific nutrients may occur as a result of a deficiency in an isolated _________.
mucosal
brush border enzymes
brush border enzyme
phases of normal digestion: _______ Impaired absorption of chylomicrons and lipoproteins may lead to steatorrhea and significant enteric protein losses
Impaired absorption of chylomicrons and lipoproteins may lead to steatorrhea and significant enteric protein losses
Fats are broken down by ______ to monoglycerides and fatty acids that form _____ with bile salts. What phase of digestion?
pancreatic lipase
micelles
intraluminal
Impaired absorption of ______ and _______ may lead to steatorrhea and significant enteric protein losses. What phase of digestion?
chylomicrons
lipoproteins
absorptive
What is gluten? Where are 4 places it is commonly found?
protein found in many grains
wheat, rye, barley and flour
celiac disease results in diffuse damage to the ______ with malabsorption of nutrients. Is it permanent or transient?
proximal small intestinal mucosa
PERMANENT!!
When does celiac present? What is the MC patient?
childhood or early adulthood
white people with a family history
What is the pathophys behind celiac disease? What will it look like on colonoscopy?
Dietary gluten triggers immune responses that damages proximal small intestine mucosa and cause VILLOUS atrophy which results in malabsorption of nutrients.
also causes humoral immune and slight T-Cell mediated response causing antibody production
will look smooth!
Diarrhea, Steatorrhea, Flatulence
Bulky, foul-smelling, floating
Dyspepsia
Weight loss
Abdominal distention
Weakness, Muscle Wasting
Growth Retardation in Children
What am I?
celiac disease- classic presentation
Fatigue, Depression
Iron-Deficiency Anemia, Vitamin B12 or Folate deficiency
Osteoporosis, bone pain
Amenorrhea, Infertility
Easy Bruising
Peripheral neuropathy, Ataxia
Dermatitis herpetiformis
Delayed puberty
Increased risk for gastric cancer
What am I?
atypical presentation of celiac disease
What is dermatitis herpetiformis? What dz is it associated with?
Pruritic papulovesicular rash - itchy autoimmune reaction
Extensor surfaces of extremities and trunk, scalp, and neck
celiac disease
**______ is the SCREENING LAB test used to help dx celiac dz? When do levels usually become undetectable? What is the important education point?
IgA TTG (tissue transglutaminase) antibody tests
undetectable after 6-12 months
pt needs to continue to eat gluten until the test is completed
What is the test that needs to be ordered to CONFIRM the dx of celiac? What anatomical location specifically? What will it show?
Endoscopic EGD mucosal biopsy of the proximal and distal duodenum is the standard method for confirmation of the diagnosis in pts with a positive serologic test for celiac
proximal and distal duodenum specifically
Blunting or a complete loss of intestinal villi
What is the management for celiac disease? When can the pt start to see improvement in symptoms?
remove all gluten! for LIFE
s/s improvement within 1-2 weeks
What is Whipple disease? How common? What is the predisposing factor? How is it transmitted?
gram-positive, non-acid fast, PAS positive bacillus
immunocompromised
fecal-oral transmission
Arthralgias
Diarrhea
Abdominal pain
Weight loss
flatulence
steortorrhea
low-grade fever
enlarged joints
lymphadenopathy
What am I?
What is the first symptom noted?
What is the MC symptom?
Whipple disease
Arthralgias- first symptom
weight loss- MC symptom
How is the dx of Whipple disease established? What will the test show?
upper endoscopy with biopsy
Macrophages containing gram-positive bacilli (periodic acid-Schiff [PAS] positive macrophages)
What do you need to do if upper EGD comes back inconclusive for Whipple disease? **What finding is pathognomic for Whipple disease?
PCR confirms diagnosis
Macrophages containing gram-positive bacilli (periodic acid-Schiff [PAS] positive macrophages)
**What is the tx for Whipple disease?
IV Ceftriaxone 1g QD for 2-4 weeks. Followed by trimethoprim-sulfamethoxazole (Bactrim) BID for 1 year
need BOTH
What is SIBO? What are four underlying causes?
Small Intestine Bacterial Overgrowth
A condition in which colonic bacteria are seen in excess in the small intestines; when present, intestinal symptoms can arise
Motility disorders
Anatomic disorders (adhesions from prior surgeries)
Other metabolic disorders (Diabetes)
Immune disorders
can be asymptomatic until vitamin deficiencies arise
bloating
flatulence
diarrhea/steatorrhea
weight loss
What am I?
What is an important history factor?
How can the dx be confirmed?
SIBO
history of GI surgery
by small intestine aspiration with bacterial cultures but NOT often done because it is invasive
What is the NON-INVASIVE diagnostic test for SIBO? How does it work? What is the important pt education? ** What is important pt education?
Carbohydrate breath test
carbohydrate substrate (lactulose/glucose) is given to the pt and if SIBO is present the bacteria consumed the carb and leads to an early peak in breath hydrogen levels which are measured in the pt’s breath
ONE day before test: Stop using all medications related to your GI tract, i.e., any medication used for acid suppression, abdominal pain/spasm, diarrhea, or constipation.
NO carbohydrates in the following categories: bread, pasta, potatoes, rice, crackers, oatmeal, cereals, or any other starchy food products
** What is the tx for SIBO?
Ciprofloxacin 500mg BID preferred for 7-10 days
What is short bowel syndrome due to? What are the symptoms?
Secondary to removal of portion of small intestine
Due to Crohn’s disease, ischemia, tumor, trauma, mesenteric infarction, volvulu
depend on the amount of bowel removed
What are the s/s of a terminal ileal resection? Extensive bowel resection? What is considered extensive?
Results in malabsorption of B-12 and bile salts
Characterized by weight loss and diarrhea d/t nutrient malabsorption
> 50% of the total length of small intestine
What is the management for acute phase short bowel syndrome? adaptation phase?
Initial 3-4 weeks after resection
Stabilize large fluid/electrolyte losses
Acid suppression with PPI IV
Parenteral nutrition, graduating to enteral feeding
Transition to oral feedings in slow and stepwise manner over a period of weeks to months
Complex carbohydrates
Low fat
Fluid management
PPIs
Antidiarrheals when needed
Antibiotics for SIBO
What is the cause of lactose intolerance? What is the role of said cause? What is the tx?
deficiency of lactase
enzyme that hydrolyzes the disaccharide lactose into glucose and galactose
tx: avoid lactose and may try lactase supplementation (Lactaid)
What do you confirm diagnosis of lactose intolerance? describe the test. What is the important pt education point?
confirmed with hydrogen breath test
After ingestion of 50g of lactose, a rise in breath hydrogen within 90 minutes is a positive test
pt need to fast 8 hours prior to test
What is paralytic ileus? What is the highlighted symptom?
A condition in which there is neurogenic failure or loss of peristalsis in the intestine in the absence of any mechanical obstruction
ABSENCE of mechanical obstruction
When is paralytic ileus commonly seen? What is the common time frame associated with return to “normal” GI motility following surgery?
commonly seen in hospitalized pts following:
Intra-abdominal processes such as recent GI or abdominal surgery
Peritoneal irritation (pancreatitis, hemorrhage)
Severe medical illness (pneumonia, sepsis, respiratory failure)
Medications that affect intestinal motility (opioids, anticholinergics)
small intestinal motility usually normalizes first, followed by the stomach (after 24-48 hours, then colon (48-72 hours)
What is the pathophys behind paralytic ileus?
Intestinal manipulation activates a network of local macrophages triggering an inflammatory response that results in muscle dysfunction
Inhibitory neural reflexes are thought to act locally through noxious spinal afferent signals that increase inhibitory sympathetic activity in GI tract with result in slowing motility
What effect do opioids have on the ileus?
decrease GI tract motility by increase resting tone while decreasing motility and emptying
N/V/obstipation, abdominal discomfort
Abdominal distention with tympany to percussion
Diminished/Absent bowel sounds
Diffuse abdominal pain
What am I?
What should be ordered as part of the work-up? What will they show?
paralytic ileus
Plain films
Distended/dilated GAS- filled loops of bowel, colon and rectum
What is the tx for paralytic ileus?
complete bowel rest, IV fluids and NG tube
slowly advancing diet
ACTIVITY!!! get the pt up and moving
remove drugs that reduce intestinal motility
What is the prevention for paralytic ileus?
If possible, avoid IV opioids
Early ambulation, initiation of clear liquid diet
Gum chewing
Why do you need to NOT chew gum before surgery?
The physiologic process behind this theory about gum is that chewing stimulates the vagus nerve, which promotes peristalsis and the release of normal GI tract hormones
What is a small bowel obstruction? When is considered a simple/partial obstruction?
MECHANICAL obstruction
Simple/partial obstruction occludes lumen only
What can a full small bowel obstruction lead to?
Full with strangulation impairs blood supply and can lead to necrosis of intestinal wall
What will the bowel look like before and after the small bowel obstruction? What is the smooth muscle doing? What are the intramural vessels doing?
Obstruction leads to progressive DILATION of intestines proximal to blockage, while distal to the blockage the bowel will DECOMPRESS
Activity of smooth muscle of small bowel increases in an attempt to propel contents past obstruction
If bowel dilation is excessive, the intramural vessels of the small intestines become compromised leading to decreased perfusion and ischemia/necrosis
**70% of small bowel obstructions are caused by _________. What is the hallmark symptom of SBO?
post-surgical adhesions
dehydration
Acute presentation
Nausea/vomiting
Colicky abdominal pain
Obstipation
High-pitched “tinkling” sounds with auscultation
dehydration
may have fever
What am I?
small bowel obstruction
If the SBO is proximal, what are some s/s? Distal?
Proximal: profuse emesis containing undigested food, upper abd. discomfort
Distal: diffuse and poorly localized crampy abdominal pain +/- Feculent vomiting
What will the bowel sounds present like in SBO?
early: hyperactive bowel sounds because bowels are trying to push the obstruction through
later: hypoactive bowel sounds
What are the s/s of intestinal ischemia?
Fever: temperature >100°F
Tachycardia: >100 beats/min
Peritoneal signs:
guarding, rigid abdomen, rebound tenderness, pain out of proportion to the examination
What study confirms the clinical diagnosis of SBO?What is the highlighted finding?
Plain x-rays of abdomen can confirm clinical diagnosis
Dilated small bowel loops with air-fluid levels
Air fluid levels with a **“ladder like” **appearance
What is the tx for SBO?
What are the major differences between paralytic ileus and SBO?
ileus is NON-mechanical
SBO: MECHANICAL obstruction
What is Ogilvie Syndrome? What can it lead to? When is it commonly seen?
Acute Colonic Pseudo-Obstruction
Spontaneous massive dilatation of the cecum and proximal colon in the absence of an anatomic lesion
progressive dilation may lead to perforation
severely, ill hospitalized patients (think ICU patients, many are on vent support)
Severely distended abdomen (right) typically NOT painful
+/- N/V
may have abdominal tenderness with some guarding
What am I?
What will the bowel sounds sound like?
Ogilvie Syndrome
bowel sounds may be normal or decreased
What parts need to be included in w/u for ogilvie syndrome?
CBC
CMP
xrays will show dilated colon: cecum to splenic flexure
CT: can be used to establish dx and r/u other causes
What is the tx for ogilvie syndrome?
conservative treatment! if no/minimal abdominal tenderness, no fever, no leukocytosis and cecal diameter smaller than 12cm
includes: A nasogastric tube and a rectal tube should be placed to decompress colon
ambulation/rolling if bed bound
d/c opioids, anticholinergics and CCB because they decrease intestinal motility
enemas, NPO, IV fluids
serial abdominal xrays
neostigmine
What medication is used in severe ogilvie syndrome? How does it work?
neostigmine
Inhibits destruction of acetylcholine and helps facilitates transmission of impulses across myoneural junction
What are the essentials of diagnosis for Ogilvie syndrome?
What qualifies as IBS? Who is the MC pt?
Chronic GI symptoms NOT EXPLAINED BY THE PRESENCE OF STRUCTURAL/BIOCHEMICAL ABNORMALITY
women in their late teens and early twenties
What are the 4 pathogensis processes that are thought to contribute to IBS?
- Abnormal motility
- Visceral Hypersensitivity: lower threshold for pain
- Intestinal inflammation
- Psychosocial abnormalities
**What is the ROME IV criteria to diagnosis IBS?
Present 1 day per week and Abd. pain with 2 or more of the following:
-Related to defecation
-Change in stool frequency
-Change in stool form
symptoms must be present for LEAST 3 months!!!
What is the manning criteria for dx IBS?
the more boxes that apply to the pt the higher the likelihood it is IBS
What are the GI alarm symptoms?
What are the REQUIRED labs when working a pt up for IBS? If all the tests are negative, then what?
CBC, C-Reactive protein, Celiac, Stool Studies
all tests are negative: NO additional testing is recommended
When is a colonoscopy recommended when working a pt up for IBS?
over 50 years old, has alarm symptoms or failed conservative treatments
What is the management for IBS? What antispasmodics are used in IBS? What antidiarrheal?
Patient Reassurance, Support, & Education
explain the pathophys and setting realistic treatment goals
food diary and dietary modification
behavioral therapy and relaxation techniques
exercise
antispasmodics:
Dicyclomine (Bentyl)
Hyoscyamine (Levsin)
antidiarrheals:
Loperamide: often used “prophylactically”
What is the medication management for IBS-D? What are the SE?
Dicyclomine (Bentyl)
Hyoscyamine (Levsin)
SE:
Urinary retention
Constipation
Dry mouth
Tachycardia
______ is a specific IBS-D medication that is used if the pt has had diarrhea for 6 MONTHS or longer? What is the drug class? What is an important to note?
Alosetron (Lotronex)
5HT3 Receptor Antagonist
IBS-D in WOMEN
______ MOA inhibits serotonin from binding to 5HT3 receptors in the intestine. Too much serotonin can cause hypermotility of the GI tract
Alosetron (Lotronex)
**What is the BBW for Alosetron (Lotronex)?
Severe Constipation and Ischemic Colitis
pts must sign consent prior to use!
_____ is a specific IBS-C drug. What drug class?
Linaclotide (Linzess)
Guanylate cyclase agonist
_____ MOA stimulates intestinal fluid secretion and transit. What are the SE?
Linaclotide (Linzess)
diarrhea and dehydration
** What is the BBW for Linaclotide (Linzess)?
Do Not Use In Patients <18 years of age!
Risk of dehydration
_____ MOA activates ClC-2 chloride channels, increasing intestinal fluid secretion and motility and reducing intestinal permeability. What is it indicated for?
Lubiprostone (Amitiza)
IBS-C in WOMEN (also used in chronic constipation)
What is the Lubiprostone (Amitiza) drug class? What are the CI?
Selective Chloride Activator
diarrhea and GI obstruction
What antidiarrheal is good for prophylactic use in IBS? What antidepressants are used in IBS? more C or D?
Antidiarrheals (Loperamide)
TCA’s - amitriptyline (Elavil), nortriptyline (Pamelor), imipramine (Tofranil)
used in IBS with DIARRHEA not constipation
What are 4 IBS pt education points?
food diary
elimination diet to figure out what triggers s/s
eat more fiber
exercise!
_____ is an easily transmittable infection that is commonly found in hospitals in patient rooms and bathrooms. Does hand sanitizer kill it? What is usually in the patient’s history?
Clostridium difficile infection
alcohol hand sanitizer does NOT kill it
recent use of abx- usually within the last 8 weeks
What abx are most commonly associated with C. diff?
Most commonly develops after use of
ampicillin
clindamycin
third-generation cephalosporins
fluoroquinolones
greenish, foul-smelling watery diarrhea 5–15 times per day with lower abdominal cramps, +/- blood or mucus
normal or reveals mild left lower quadrant tenderness
What am I?
What will the WBC level be?
mild/moderate C. diff
Serum WBC greater than 15,000/mcL
fever; hemodynamic instability; abdominal distention, pain, and tenderness
profuse diarrhea (up to 30 stools/day)
What am I?
What will the WBC level be?
severe C. diff (fulminant)
WBC usually greater than 30K
What are the potential complications associated with C. diff?
Dehydration
Weight loss
Hemodynamic instability
Toxic megacolon
What s/s should make you suspect C. diff as a possible cause? What are the 3 risk factors?
patients with acute diarrhea and ≥3 loose stools in 24 hours
risk factors:
recent antibiotic use
hospitalization
advanced age
Name the two tests that can confirm the dx of C. diff? What are the 2 stool studies used?
positive nucleic acid amplification test (NAAT) for C. difficile toxin gene
positive stool test for C. difficile toxin(s)
Stool studies:
Nucleic Acid Amplification testing (PCR)
Rapid enzyme immunoassays (EIAs)
What is the order of stool studies that you order in C. diff? Do they both need to be positive?
Nucleic Acid Amplification testing (PCR) assays d/t higher sensitivity (97%) FIRST then if positive move on to
Rapid enzyme immunoassays (EIAs) for C. diff toxins
need both to be positive to confirm diagnosis of C diff
When would you want to order imaging for C. diff?
Can do abd. Radiographs or abd. CT scans with severe or fulminant symptoms to look for colonic dilation or wall thickening
What is the tx for mild/moderate C. diff? Severe dz? What is considered severe dz?
mild/moderate: Fidaxomicin (Dificid) 200mg BID or Vancomycin 125mg QID for 10 days
severe: Vancomycin 500mg QID plus Metronidazole (Flagyl) 500mg IV q8h
severe: (WBC count >15,000)
What are the indications for surgical consultation in a pt with C. diff? (consider reading through it a couple times, doubt we have to memorize it)
What is the surgical tx for C. diff?
Total abdominal colectomy
or
diverting loop ileostomy/colonic lavag
How common is C. diff relapse? What is the tx for first C. diff relapse?
up to 20% have relapse in 8 weeks
First episode of recurrent infection usually responds promptly to a second course of the same regimen used for the initial episode or a prolonged vancomycin 125mg tapering regimen
What is the tx for the second relapse of C. diff?
a 7-week tapering regimen of vancomycin is recommended:
125 mg orally four times daily for 14 days;
twice daily for 7 days;
once daily for 7 days;
every other day for 7 days;
and every third day for 2 weeks
What section ischemic colitis the most common?
effects prominent at “watershed” regions of colon where collateral blood flow limited
splenic flexure is MC (left colic flexure)
Rectosigmoid junction
What 3 major arteries supply the colon? Who is the MC patient to have ischemic colitis?
Superior mesenteric artery
Inferior mesenteric artery
Internal Iliac arteries
older patients who have atherosclerotic disease, episodes usually occur spontaneously following some sort of sx (cardio/aortoiliac surgery)
What are some non- surgery related causes of ischemic colitis?
medications
illicit drugs- cocaine use
extreme exercising
What are 4 factors that contribute to ischemic colitis in young patients?
Vasculitis
Coagulation disorders
Estrogen therapy
Long distance running
anything that reduces perfusion to the intestine
onset of mild cramping abd pain
Tenderness over affected bowel
Diarrhea with hematochezia
Associated with urgent desire to defecate
Mild to moderate amount of rectal bleeding or bloody diarrhea occurring within 24 hours of onset of abd pain
can present acute or chronically
What am I?
ischemic colitis
What is the classic clinical description for ACUTE intestinal ischemia?
“abdominal pain out of proportion to the physical examination.”
What is the classic clinical description for CHRONIC intestinal ischemia? What does it lead to?
complain of recurrent abdominal pain after eating
develop food fear and can lose a considerable amount of weight
What is first line imaging for ischemic colitis? What will it show?
CT of abdomen WITH contrast
“Target,” “thumbprinting”, or “double halo” sign on CT:
What does “Target,” “thumbprinting”, or “double halo” sign on CT reflect?
hyperdensity of mucosa and muscularis of bowel wall
These changes typically reflect the initial episode of transient ischemia and subsequent reperfusion injury than ongoing ischemia
Everyone suspected of ischemic colitis should receive ______ within 48 hours unless ?????? What is the diagnostic test for ischemic colitis?
Colonoscopy
unless pt has evidence of irreversible damage on CT
colonoscopy
What is the tx for ischemic colitis?
supportive care and no specific therapy:
Bowel rest: NPO
IV fluids
Observation
broad spectrum abx
+/- anticoag therapy but NOT indicated for most patients unless the cause of ischemic colitis is due to mesenteric venous thrombosis
When would you consider sx as a tx option for Ischemic colitis?
Ongoing pain
Persistent fever
Leukocytosis
Peritoneal irritation
GI bleeding
What is the MC congenital abnormality of the small bowel? How does it present?
Meckel’s Diverticulum
Majority asymptomatic, if so, before age 10 usually found incidentally on testing
**What are the True congenital diverticulum that follows the “rule of 2s?”
Present 2% of population
2ft from ileocecal valve
Symptomatic 2% of patient
if Meckel’s diverticulum is symptomatic, how will it present? **What is the definitive tx?
Generally presents with crampy abd pain, N/V, bleeding
**surgery
What is the way to definitively diagnosis meckel’s diverticulum? What type of scan is it? What is it looking for?
“Meckel’s Scan”
Nuclear medicine scan: looks for ectopic gastric mucosa
Where is diverticular dz MC? What does it result from? What are the 3 forms?
M/C in Sigmoid/Left Colon
caused by incrased intraluminal pressure
Uncomplicated Diverticulosis
Diverticulitis
Bleeding Diverticula
What 3 condition increased intraluminal pressure? What does it increase your risk for? more common in younger or older people?
Chronic constipation
Low Fiber Diet
Colonic musculature works to move hard stools, develops hypertrophy, thickens, gets rigid, and fibrotic
diverticular disease
incidience increase with age
What is uncomplicated diverticulosis? What are some s/s? What is the tx?
More than 90% have uncomplicated disease and no specific symptoms, just have the pouches
some may have abd pain, chronic constipation or fluctuating bowel habits
high fiber diet
What will the PE show on a pt with Uncomplicated Diverticulosis?
PE is usually normal
may see mild LLQ tenderness
What will acute diverticulitis present like? **What is the highlighted one? What will the PE show? Lab?
**Acute LLQ abdominal pain
Low grade Fever
Bowel changes (diarrhea or constipation)
N/V
Blood in stool
PE:
LLQ tenderness may feel palpable mass
lab:
Leukocytosis mild to moderate
What is the imaging needed with symptomatic diverticular disease? Then what do you need to move on to?
CT of the abdomen is obtained especially those with fever, leukocytosis, and signs of sepsis or peritonitis or with immunocompromise
colonoscopy 4-8 weeks after resolution of symptoms is indicated for patients who respond to acute management
Why do you not want to a colonoscopy in a pt with active diverticular disease?
Contraindicated during the initial stages of acute attack because of the risk of free perforation
What is the tx for mild diverticular dz?
conservative measure!
liquid diet for 2-3 days, oral abx
need to start high fiber diet once s/s have resolved and for long term management!
What is the tx for severe diverticular dz? When should you start to see improvement?
Pts should be NPO with IV fluids
Piperacillin-tazobactam IV for 5-7 days and then switch to oral Cipro + Metronidazole 10-14 days PO
Should see improvement within 2-3 days
When should sx be considered for severe Diverticular Disease?
Surgery for those that have SEVERE disease or do not improve after 72 hours
What is the criteria for inpt diverticulits tx?
** What is the MC cause of a LOWER GI bleed? What is the tx?
**Diverticular Bleed
may resolve on its own but may need Colonoscopy with cauterization of bleed
What is the imaging of choice for acute diverticulitis?
abdominal CT
