DSA - Inflammatory Bowel Disease (Completed) Flashcards
What two diseases do we consider to fall under the IBD category?
- Ulcerative colitis (UC)
- Crohn Disease (CD)
What gene do we associate with Crohns?
CARD15/NOD2 of chromosome 16p
In ulcerative colitis type IBD 70% of patients have what serum marker?
Anti-neutrophil cytoplasmic antibodies (ANCA)
In Crohn’s disease type IBD 60-70% of patients have what type of antibodies present?
Saccharomyces cerevisiae (ASCA)
What is the age of peak occurrence for IBD?
- 15-30
- 60-80
What’s the most likely and least likely ethnicity to develop IBD?
Most likely: Jewish
Least likely: asian
What is the mainstay therapy for IBD?
- 5-aminsalicylic acid derivatives
- corticosteroids
- immunomodulating agents
- biologic agents
What are the common extraintestinal manifestations of IBD?
- peripheral arthritis
- Erythema nodosum
- pyoderma gangrenosum
- DVTs
- nephrolithiasis w/ urate or calcium oxalate stones in CD
Infectious enterocolitis is endoscopically indistinguishable from ulcerative colitis. How do we differentiate the two?
- Stool studies
- biopsies
Compare and contrast ulcerative colitis from crohns diseases. What are the key characteristics of UC?
- pANCA positive
- Effects mucosal layer only
- colon only (terminal ileum, “backwash”)
- continous lesion
- toxic megacolon
- smoking is protective
Compare and contrast ulcerative colitis from Crohn’s disease. What are the key characteristics of Crohn’s disease?
- ASCA positive, ANCA negative
- skip lesions
- full thickness (transmural)
- string sign (strictures)
- prescence of fissures
- Smoking worsens disease
- cobblestoning
- Segmented ulcerated mucosa of the terminal ileum
Crohn’s disease is defined with non-caseating granulomas. What other disease also has this feature?
Sarcoids
What are the clinical manifestations of ulcerative colitis?
- Erythema nodosum
- Frequent bloody diarrhea
- Mucus
- Tenesmus - inclination to evacuate bowel
- Fulminant colitis - rapidly worsening symptoms w/ signs of toxicity
What are the clinical manifestations of Crohn’s disease?
- Insidious onset
- diarrhea (w/o blood)
- growth retardation in children
- acute ileitis mimicking appendicitis
- anorectal fissures
- fistulas
- abscesses
What three clinical courses can Crohn’s disease fall into?
- Inflammatory
- stricturing
- fistulizing
What complications are associated with ulcerative colitis?
- Toxic megacolon
- colonic perforation
- pyoderma gangrenosum
- frequent bloody diarrhea
What complications are associated with Crohn’s disease?
- Intestinal obstruction
- bile salt malabsorption —> gallstones/oxalate kidney stones
- Abscess
- fistula (ex. Enterovesical fistula)
- fissures
- adhesions
What is the relationship between smoking and ulcerative colitis?
- Onset of ulcerative colitis often follows cessation of smoking
- UC is more common in non smokers and former smokers
What is the relationship between smoking and Crohn’s disease
- smoking is correlated with increased risk of developing Crohns disease
- stopping smoking has no effect
What influence does appendectomy on development of ulcerative colitis or Crohn’s disease?
Appendectomy before the age of 20 for acute apendicitus associated with a reduced risk of developing UC.
No relation to CD development
In regards to colon cancer, what considerations need to be taken with ulcerative colitis?
- Risk of colon cancer increases with UC that is closer to the rectum
- Ingestion of folic acid reduces risk
- Colonoscopies recommended every 1-2 yrs beginning 8 years after diagnosis of UC
What are two rare colon cancers see as a development from Crohn’s disease?
- Lymphoma
- Small bowel adenocarcinoma
What is the key diagnostic test for UC?
Sigmoidoscopy
What is the key diagnostic test for Crohn’s disease?
- Sigmoidoscopy/colonoscopy
- barium enema
- upper GI and small bowel series
What labs are you going to want/see in a patient with CD or UC?
- Complete blood count
- serum albumin
- increased ESR (erythrocytes sedimentation rate)
- increased CRP
- Increased fecal calprotectin (intestinal inflammation)
- stool specimen
- hypokalemia (UC only)
Sigmoidoscopy is the diagnostic tool of choice for UC. Using this tool how would you characterize the mucosa of this patient?
- edema
- friability
- mucopus
- erosions
Colonoscopy is usually performed first in CD to evaluate the colon and terminal ileum. What would you see in the case of CD?
- Aphthoid linear or stellate ulcers
- strictures
- segemnetal involvement with areas of normal-appearing mucosa adjacent to inflamed mucosa
- shows only the colon and terminal ileum
granulomas on biopsy are highly suggestive of Crohn’s disease
If you are having trouble discerning UC from CD what diagnostic test can be used and what does the test tell you?
Capsule Imaging
measures:
- Autoantibodies to P-ANCA (UC)
- Antibodies to yeast saccharomyces cerefisiae (CD)
An emergent CT of the abdomen identifies an abscess as a result of complication of Crohn’s disease. What is your course of action?
- adminsiter broad-spectrum antibiotics
- percutaneous drainage or surgery usually required
What kind of diet is indicated for patients with CD, especially those with symptoms of intestinal obstruction?
- Low-roughage diet (no raw fruits, vegetables, nuts, popcorn)
Because of the penetrating nature of Crohn’s disease. What is a major concern?
Sinus tracts that penetrate through the bowel where they may be contained or form fistula to adjacent structures
A complication of CD is perianal disease. Describe the complications associated with perianal disease.
- painful skin tags
- anal fissures
- perianal abscesses
- fistulas
identified with pelvic MRI
treated with oral abs (metronidazole or cipro)
(True/False) unlike ulcerative colitis, severe hemorrhage is unusual in Crohn’s disease
true
Which diagnostic study is best for evaluating a patient with CD’s small bowel?
- CT w/ contrast or MR enterography (most common)
- barium upper GI series w/ small bowel follow-through (Barium UGI w/ SBFT)
Why should barium enemas not be performed in acute ulcerative colitis?
May precipitate toxic megacolon
but if performed will show “Lead-pipe” loss of haustra
What is the role of plain abdominal radiographs in UC?
Used in patients with severe colitis to look for significant colonic dilation
Resection of more than 100 cm of terminal ileum in the treatment of Crohns Disease may lead to what? What is recommended for this?
Fat malabsorption
- low fat diet recommended
- parenteral vitamin B12 recommended
What considerations must be made with involvement of the terminal ileum in Crohn’s Disease or prior ileal resection?
There will be a reduced absorption of bile acids that may induce secretory diarrhea from the colon
Patients with extensive ileal disease requiring more than 100 cm of ileal resection see what as a consequence?
Steatorrhea
Severe bile salt malabsorption leading to steatorrhea
Patients with extensive ileal disease requiring more than 100 cm of ileal resection should not be given what?
Bile-salt binding agents because these will exacerbate steatorrhea
In patients with extensive ileal disease requiring more than 100 cm of ileal resection bile salt-binding agents should not be given because of the tendency to exacerbate steatorrhea. Why is this the case?
Unabsorbed fatty acids bind w/ calcium, reducing its absorption and enhancing the absorption of oxalate
Oxalate kidney stones may develop
cholesterol gallstones may develop (decrease bile salts)
In severe inflammatory bowel disease glucocorticoids are a treatment. What are the adverse events that commonly occur during short-term systemic therapy?
- Mood changes
- insomnia
- buffalo hump - edema
- weight gain (striae)
- Increased serum glucose
- acne
- moon facies
In the treatment of inflammatory bowel disease 5-ASA (mesalamine) can be used to maintain UC remission. What is an important side effect of the compound to be aware of?
Acute interstitial nephritis
In the treatment of inflammatory bowel disease AZO compounds (sulfasalazine) can be used to maintain UC remission. What is important to note about the administration of this drug?
Always administer with folate
What is a curative treatment for ulcerative colitis?
Procto-Colectomy w/ ileostomy
What is a biological treatment used in inflammatory bowel disease?
Monoclonal antibodies to TNF and Integrin
Biological used in the treatment of inflammatory bowel disease include antibodies to TNF and integrin. Tests need to be performed prior to okaying the use of these agents in treatment. What tests need to be run?
Screening for latent tuberculosis (PPD and Chest-XR)
- Tx: puts patients at increased risk of TB development
Liver biochemical tests should be monitored
- Anti-TNF/Integrin can cause severe hepatic reactions leading to acute hepatic failure
Anti-TNF therapy is one of two biological (anti-integrin) used in the treatment of inflammatory bowel disease. What does administration of anti-TNF (usually combined with thiopurine) specifically increase the risk of in the patient?
- Non-melanoma skin cancer
- non-Hodgkin lymphoma
Immunomodulators in addition to biologics, sulfasalazine/aminosalicylates, and glucocorticoids can be used to treat inflammatory bowel disease. Immunomodulators such as azathioprine or 6-mercaptopurine (6-MP) are steroid-sparing agents used in the treatment of CD and UC. What must be done prior to treatment?
Measurement of TPMT thiopurine methyltransferase functional activity recommended prior to initiation
Due to high risk of _______ _______ _________, prophylaxis should be administered to all hospitlizaed IBD patients
High risk of venous thromboembolic disease
