GI- Colon Flashcards
Define Diverticulosis
Characterized by sac-like mucosal projection through the muscular layer of the colon and/ or rectum.
Caused in part by a low-fiber, high fat diet.
Complications of Diverticulosis
GI Bleed (painless) Diverticulitis (inflammation of the diverticulum)
Diverticulitis complications:
- Abscess formation
- Fistula formation
- sepsis
- large bowel obstruction
Signs and symptoms of diverticulosis/ diverticulitis
LLQ pain and tenderness Diarrhea or constipation Bleeding Leukocytosis Fever
Infection symptoms indicate diverticulitis
Cause of diverticulitis
stool or other debris impacts within the outpouched mucosa, causing obstruction leading to overgrowth of bacteria and inflammation
Diagnosis of diverticulitis / diverticulosis
ITIS: Best initial and confirmation- CT scan. CT rules out complications.
OSIS: most accurate is colonoscopy
Tx diverticulitis
W/o complications: ABX - cover bowel flora (fluoquinolone or ceftriaxone + metro), bowel rest (NPO),
Perf or abscess: may need surgical resection.
Post diverticulitis follow up
Colonoscopy for cancer screening ( colon carcinoma with perf can mimic diverticulitis)
Avoid endoscopy during active diverticulitis (risk of perf)
Maintain high fiber diet.
Prevention of diverticulitis
Bran
Psyllium
Methycelulose
Increased dietary fiber
decrease rate of progression and complications
How is diarrhea categorized?
- Systemic
- Osmotic
- Secretory
- Malabsorptive
- Infectious
- Infectious
- Exudative
- Altered Intestinal transit.
Define osmotic diarrhea
Caused by non absorbable solutes that remain in the bowel, where they retain water (lactose or sugar intolerance).
When ingestions of offending substance stops, diarrhea stops.
What causes secretory diarrhea?
Results when the bowel secretes too much fluid. often due to bacterial toxins, VIPoma, or bile acids.
persists even when patient stops eating.
What are common causes of malabsortive diarrhea?
Celiacs disease
Crohns disease
Postgastroenteritis (depletion of brush boarder)
improves with bowel rest.
rare causes: tropical sprue and Whipple disease
Common clues to infectious diarrhea
- Fever
- WBC in stool (invasive app only)
- Travel history
- Hikers/stream water
- Hx abx use (c.diff)
Common organisms of infectious diarrhea
Invasive: Shigella, Salmonella, Yersinia, Campylobacter
E.coli
Giardia
C. Diff
Cause of exudative dirrhea
Results from inflammation in the bowel mucosa that causes seepage of fluid. Usually due to IBD or cancer.
similar to infectious with fever and WBC but no organisms.
Common causes of diarrhea due to altered intestinal transit
Seen after bowel resections, in patients taking meds that interfere with bowel function and in patients with hyperthyroidism or neuropathy.
Ddx: factitious diarrhea- laxative abuse
presentation of malabsorption diarrhea
steatorrhea- oily greasy floating and foul smelling diarrhea.
Weight loss
Deficiencies and manifestations with malabsorption
Vit D- hypocalcemia, osteoporosis
Vit K- Bleeding, easy bruising
Vit A- night blindness, dry eyes, dry skin
Vit B12- megaloblastic anemia, neuropathy
(B12 need an intact abdominal wall and pancreatic enzyme)
What is the presentation of Whipple disease? Tx?
Arthralgias Ocular findings Neurological abnormalities (dementia, seizures) Fever Lymphadenopathy
Tx: TMP/SMX
Signs and symptoms for celiac disease
Iron Deficiency Dermatitis herpetiformis Diarrhea Malabsorption symptoms Failure to thrive Neuropathies
Clinically indistinguishable from tropical sprue
Diagnosis of malabsortive diarrheas
Celiacs: Anti-tissue tranglutaminase (TTG)- best initial
Most accurate: small bowel biopsy that showed flattening of the villi and rules out lymphoma.
Whipple and tropical: biopsy shows organisms.
What Abx predispose a person to C.diff
Clindamycin has the highest incidence but any abx can cause diarrhea.
presents several days or weeks after the start of abx.
Best initial and most accurate test for C. Diff.
BIT: stool C. diff toxin
Most accurate: NAAT
Tx C.Diff
Most effective: oral vancomycin. If no response switch to fidaxomicin.
Both more efficacious then oral metro.
If oral therapy cannot be used, use IV metro. IV Vanc cannot pass the bowel wall.
What defines fulminant C. Diff? How is treatment different?
WBC >15,000
Metabolic acidosis
High Lactate
High Creatinine (1.5 X baseline)
Tx: both vancomycin and metro
Diarrhea from carcinoid syndrome
Best initial test and Tx
Diarrhea, Flushing, cardiac abnormalities.
BIT: 5 HIAA
Tx: octreotide
How to recognize IBS?
Patients are anxious, hx of diarrhea aggravates by stress, bloating, and pain relieved by dedication, mucus in stool. psychosocial stressors.
Normal physical and Labs. Diagnosis of exclusion.
MOST LIKE DIAGNOSIS if: no positive findings, young adult, female (F:M 3:1)
TX IBS
- Fiber in diet
- Antispasmodic agents (dicyclomine, peppermint oil, hyoscyamine)
- TCA
Diarrhea prominent: rifaximine, aldosterone, eluxadoline, probiotics.
Constipation prominent: Fiber, polyethylene glycol, lubiprostone (CC activator), linaclotide (guanylate cyclase agonist)
Characteristics of IBD Crohns:
- Place of origin
- pathology thickness
- progression
- location
- classic lesions
- Origin: distal ileum
- Thickness: transmural
- Progression: irregular (skip- lesions)
- Location: mouth to anus
- Classic lesions: Cobblestone, string sign on barium xray
Characteristics 2 of IBD Crohns:
- Bowel Habit changes
- complications
- colon cancer risk
- surgery
- Bowel: obstruction, abdominal pain
- Complications: Fistula, abscesses, perianal disease
- Cancer: slightly increase risk
- Surgery: NO (may make worse) only if obstruction
Characteristics of IBD Ulcerative colitis :
- Place of origin
- pathology thickness
- progression
- location
- classic lesions
- Origin: rectum
- Thickness: mucosa/ submucosa only
- Progression: proximal, continuous from rectum
- Location: Colon only, rarely extends to ileum
- Classic lesions: pseudopolyps, lead pipe on barium x-ray
Characteristics 2 of IBD Ulcerative colitis:
- Bowel Habit changes
- complications
- colon cancer risk
- surgery
- associated disease
- Bowel: Bloody diarrhea
- Complications: toxic mega colon
- Cancer: markedly increased risk
- Surgery: colectomy is curative
- Association: primary sclerosis cholangitis
Extraintestinal manifestations of IBD
- Uveitis
- Arthritis/ Arthalgias
- Ankylosing Spondylitis
- Skin manifestations: (Erythema Nodosum, Erythema Multiforme, pyoderma gangrenous)
- Anemia
- Failure to thrive.
Which IBD is related to:
antineutrophil cytoplasmic antibody (ANCA)
anti-saccharomyces cervusuae antibody (ASCA)
ANCA- UC
ASCA- Crohns
How is IBD treated?
Steroids for exacerbations (budesonide, prednisone)
5- aminosalicylic acid (5-asa) derivatives- mesalamine
ABX: cipro and metro
Calcium and vit D
Anti-TNF or Anti IL12/23 for fistula and severe disease.
if very refectory: a-intergin inhibitor (vedolizumab)
What drugs are Anti-TNF? Anti- IL12/23?
Anti-TNF: infliximab, cetrolizumab, golimumab, certolizumab
Anti-IL 12/23: ustekinumab
What causes toxic mega colon? presentation?
Classically seen with IBD (UC) and infectious colitis (C.diff).
patients have: high fever leukocytosis abd pain rebound tenderness dilated segment of colon
Tx toxic mega colon
MEDICAL EMERGENCY: Discontinue all antidiarrheals NPO/ NGT IV fluids. ABX: ceftriaxone +metro Steroids Surgery if perforation
Signs and symptoms of short bowel syndrome
Diarrhea dehydration Malnutrition Weight Loss Steatorrhea Nutrient deficiency( vit A,D,E,K, calcium, mag, iron, zinc)
Hx: Small bowel resection surgery
Tx short bowel syndrome
IV hyperalimentation
loperamide (slow bowel)
Teduglutide (GLP agonist- slows bowel)
Vitamin Supplementation
What causes small intestine bacterial overgrowth?
SIBO results from progressive dilation of the small bowel as the body adapts to resection. ileoccal valve loss lets bacteria in.
Presentation and Tx of SIBO
Flatulence, bloating, diarrhea, steatorrhea, positive small bowel aspirate cultures.
Tx: ABX (rifaximin)
Define and cause of microscopic colitis
Normal tissue with inflammation on biopsy. Colitis that is only seen under microscope.
Cause by chronic, non bloody, watery diarrhea. Autoimmune Hx.
Tx of microscopic colitis
all varieties (lymphocytic, collagenous, mastocytic) respond to steroids.
Anorectal abscesses
anal crypt gland obstruction allowing bacterial overgrowth
Management of anorectal abscess
Prompt I&D.
Abx therapy consideration
Whan ins systemic abx therapy indicated for an anorectal abscess
Systemic illness (fever)
Cellulitis
Pts risk of severe infection (DM, immunocompromised)
Abx decreases risk of fistula formation
