GI: Block 2- 10 11 12 15 16 Flashcards
When are Virtual Endoscopy’s indicated?
Failed colonoscopy
Eval colon proximal to obstructing lesion
CRC screening in PTs w/ contraindications to endoscopy
PTs refusing other screening options
What two test/imaging modalities are specific to anorectal pathology?
Rigid sigmoidoscope
Anoscope
Antibiotic associated colitis is AKA ?
Pseudomembranous colitis, not the same is diarrhea
True colitis is nearly always a result of an infection from ?
When is it most commonly seen?
C Diff- Sx of mild diarrhea up to fulminant dz w/ toxic megacolon
Nosocomial- cause of diarrhea in 20% hospitalized PTs for +3 days
What are the most common causative agents that allow C Diff to flourish?
Ampicillin Clindamycin 3rd Generation Cephalosporins Fluoroquinolons Almost all ABX have been implicated
What are the S/Sx of mild-moderate antibiotic associated colitis?
Mild/Moderate diarrhea- watery/green/foul/mucus
Cramping
CBC showing mild leukocytosis <15K
What are the S/Sx of severe antibiotic associated colitis?
Profuse diarrhea Fever <101.3 Hypoalbuminemia One of the following: Ab pain w/ diffuse TTP or, CBC leukocytosis >15K
Criteria for Antibiotic Associated Colitis: Fulminant Disease
One of these: Admit to ICU HOTN- >100mm SBP Fever >101.3/38.5*C Ileus/abdominal distension Changes in mental status WBC >35K Serum Lactate >2.2mmol End organ failure/mechanical ventilation
Define Antibiotic Associated Colitis: Pseudomembranous Colitis
Pseudo membrane formations on mucosal surface of bowel causing severe inflammation that may manifest as yellow/off-white plaques up to 2cm in diameter
How is C Diff toxin identified
Stool Assays:
PCR- study of choice
Enzyme Immunoassay- reqs 2 sample testing
When is imaging indicated for Antibiotic Associated Colitis
Contrast enhanced CT of abdomen and pelvis
PTs w/ evidence of fulminant dz to evaluate for toxic megacolon, perforation or surgical indications
What are some complications of fulminant disease?
Hemodynamic instability Hypoalbuminemia causing hypercoagulability Resp Failure Metabolic acidosis Toxic Megacolon Bowel perforation
What are the treatment steps for antibiotic associated colitis?
Admit
D/c ABC offenders
Infection control/prevent spread
Correct fluid/E+ loss
What is the first line treatment option for antibiotic associated colitis?
Metronidazole 500mg PO TID x 10days
If PT unable to take metronidazole= Vancomycin 125mg PO QID x 10 days
If no improvement on Metron x 5-7 days, switch to Vancomycin
What is the cost difference between Metronidazole and Vancomycin?
Metron= $22 Vanvomycin= $680
What is the preferred treatment regime for severe antibiotic associated colitis?
Vancomycin 125mg PO QID x 10 days
What are the treatment regimes for fulminant diseases?
Vancomycin 500mg PO QID
Metronidazole 500mg IV q8hrs
Vancomycin 500mg PR QID in 500mL NS enema
AND, early surgical consult
What are the characteristics of antibiotic associated colitis treatment relapse?
25% will relapse in 14 days
Repeat PO ABX
Relapse req 7 day taper of Vancomycin
Adjuncts: probiotics, fecal transplant
Define Toxic Megacolon
Acute Toxic Colitis/Toxic Colitis Total/segmental colonic dilation Non-obstructive Larger than 6cm Systemic Toxicity- toxemia
Toxic Megacolon may be a complication of ?, usually what form?
IBDz
Ulcerative Colitis
What is the diagnostic criteria for Toxic Megacolon?
Radiographic evidence of colon distension >6cm plus three of: FLAP Fever HR +120bpm Leukocytosis >10.5 Anemia AND one of: HEAD Dehydration Altered mental status E+ abnormality HOTN
How is Toxic Megacolon treated?
Reduce distension to prevent perforation
Correct fluid/E+ disturbance
Treat toxemia/precipitating factors
Surgical consult
Define Diverticulum
Sac-like protrusion of colonic wall that is the same color as the tissue around it
Characteristics of Colonic Diverticula
Most are A-Sx, various sizes Sigmoid/Descending dominant Pathogenesis- inc intraluminal pressure Low fiber Dec water intake