pathology 3 - Malabsorption syndromes-Inflammatory bowel diseases Flashcards
A patient has diarrhea, steatorrhea, weight loss, weakness, and vitamin/mineral deficiencies; she likely suffers from what type of illness?
A malabsorption syndrome
A child develops greasy stools and failure to thrive after the addition of wheat to her diet. She has autoantibodies to what substance?
Gluten (gliadin), suggesting celiac disease
Celiac disease primarily affects what part(s) of the bowel?
Distal duodenum and/or proximal jejunum
Unlike a patient with celiac disease, a patient with tropical sprue can be treated with which class of drugs?
Antibiotics
A patient with tropical sprue has a colonoscopy with biopsy. Which sections of the GI tract are likely to be affected?
The entire small bowel
An 80-year-old man presents with Whipple disease. A Gram stain of the causative organism would show what?
Gram-positive rods (Tropheryma whipplei)
A patient with suspected Whipple disease has a biopsy with PAS staining. Where would you look to confirm foamy macrophages?
Intestinal lamina propria, mesenteric lymph nodes
A woman is diagnosed with Whipple disease and wants to know about potential complications. What non-GI symptoms might also occur?
Cardiac symptoms, Arthralgias, Neurologic symptoms (these symptoms occur mostly in older men)—think foamy whipped cream in a CAN
What is the most common disaccharidase deficiency?
Lactase deficiency
A boy gets diarrhea any time he eats dairy products. If he were to have an intestinal biopsy, what is the expected appearance of the villi?
Normal villi in lactase deficiency (as opposed to celiac disease, in which villi are blunted)
A child has diarrhea and a rash on the extensor surfaces that resolves with dietary modification. It is associated with which GI pathology?
Lactose (the inability to cleave lactose via lactase causes an osmotic diarrhea)
A patient with lactase deficiency undergoes a lactose tolerance test. Following the administration of lactose, what do you expect to see?
Osmotic diarrhea and a rise in blood glucose
A 15-year-old boy with chronic respiratory infections due to Pseudomonas has fatty stools. What is the most likely pathophysiology?
Pancreatic insufficiency due to sludging of pancreatic secretions, as a result of cystic fibrosis
A chronic alcoholic refuses to stop drinking. He is finally diagnosed with chronic pancreatitis. What do you expect to see on stool studies?
Neutral fat in stool (chronic pancreatitis leads to pancreatic insufficiency, fat malabsorption, steatorrhea, and findings of fat in stool)
A patient is diagnosed with ampullary cancer. What do you expect to see on stool studies?
Steatorrhea (obstructive cancers of the pancreatic head lead to pancreatic insufficiency, causing increased neutral fat in the stool)
Pancreatic insufficiency causes the malabsorption of which macronutrient(s)?
Fat, the fat-soluble vitamins (A, D, E, K), sometimes vitamin B12
An 70-year-old man with arthralgias, cardiac and neurologic symptoms gets a duodenal biopsy. What is likely to be found with PAS stain?
Foamy macrophages (this is Whipple disease—remember foamy whipped cream)
A patient with pancreatic insufficiency is given the D-xylose absorption test. What results do you observe?
Normal urinary excretion (if decreased excretion is seen, then the pathology is due to intestinal mucosa defects or bacterial overgrowth)
A child has diarrhea and a rash on the extensor surfaces that resolves with dietary modification. It is associated with which GI pathology?
Associated with celiac disease (this is dermatitis herpetiformis)
In a patient with celiac disease, what malignancy would the patient be at increased risk for?
T-cell lymphoma
A patient with diarrhea that occurs on a wheat-containing diet undergoes colonoscopy. What histologic findings are expected?
Blunting of villi and the presence of lymphocytes in the lamina propria (this is celiac disease)
A patient is found to have gluten insensitivity. What is the pathophysiology of his disease?
Antibodies destroy villi (primarily in the distal duodenum and proximal jejunum), thereby decreasing mucosal absorption and causing diarrhea
A patient has anti-endomysial, anti-tissue transglutaminase, and anti-gliadin antibodies. What serotypes are associated with this syndrome?
HLA-DQ2, HLA-DQ8
man returns from the Bahamas with complaints of diarrhea and decreased mucosal absorption. Will this patient respond to antibiotics?
The patient has tropical sprue and will respond to antibiotics
A patient presents with extremely itchy rashes on her knees and elbows. IF shows IgA deposits at dermal papillae. How do you treat her?
A gluten-free diet will resolve the skin lesions. (this is dermatitis herpetiformis, which is a finding in celiac disease)
What is generally accepted as the etiology of Crohn disease?
Disordered immune responses to intestinal bacteria
A man with ulcerative colitis asks if his condition was caused by a bacteria or virus. You explain that his disease a type of what process?
It is an autoimmune condition, possibly a disordered response to bacteria, but not directly caused by said bacteria
A 20-year-old patient has recurrent diarrhea that is sometimes bloody, weight loss, oral ulcers, and perianal fistulas. Likely diagnosis?
Crohn disease
What type of inflammatory bowel disease tends to show skip lesions (noncontiguous areas of mucosal involvement)?
Crohn disease
A patient has a continuous segment of friable colonic mucosa that abruptly stops in the mid-transverse colon. First-line treatment is what?
Aminosalicylates (this is ulcerative colitis, which typically has colonic inflammation always involving the rectum)
A man has transmural colonic inflammation with noncaseating granulomas and lymphoid aggregates. What cell type mediates this pathology?
Th1 cells (this is Crohn disease)
Is perianal disease mainly a complication of Crohn disease, ulcerative colitis, or both?
Crohn disease
A young woman diagnosed with ulcerative colitis asks if she will have issues with malabsorption. How do you respond?
Malabsorption is unlikely with ulcerative colitis, since it is often limited to the colon (unlike Crohn disease)
Is toxic megacolon mainly a complication of Crohn disease, ulcerative colitis, or both?
Ulcerative colitis
strictures
Crohn disease (strictures can lead to obstruction and require multiple resections of small bowel)
A 26-year-old man with abdominal pain and mucous in the stool has transmural inflammation of the ileum. What complications may occur?
Migratory polyarthritis, erythema nodosum, pyoderma gangrenosum, ankylosing spondylitis, aphthous ulcers, uveitis (this is Crohn disease)
A patient suffering from primary sclerosing cholangitis is likely to also carry a diagnosis of which inflammatory bowel disease?
Ulcerative colitis
How does mucosal and submucosal inflammation with pseudopolyps and freely hanging mesentery in ulcerative colitis appear on imaging?
Lead-pipe appearance (the loss of haustra, giving the colon its segmented appearance, leads to this appearance)
tx ulcerative
ASA preparations Sulfasalazine, 6-mercaptopurine, infliximab, colectomy as last resort (this is ulcerative colitis)
Describe the gross morphology typically found in Crohn disease.
Cobblestone mucosa, creeping fat, bowel wall thickening (string sign on X-ray), linear ulcers, fissures, fistulas, transmural inflammation
Describe the gross morphology typically found in ulcerative colitis.
Mucosal and submucosal inflammation. friable mucosa with freely hanging mesentery (loss of haustra causes lead-pipe appearance on imaging)
Name at least two complications of ulcerative colitis.
Malnutrition, primary sclerosing cholangitis, toxic megacolon, colorectal carcinoma (worse with right-sided colitis or pancolitis)
Name at least two extraintestinal manifestations of ulcerative colitis.
Pyoderma gangrenosum, erythema nodosum, primary sclerosing cholangitis, ankylosing spondylitis, aphthous ulcers, uveitis
What mnemonic can help you to remember the basics of Crohn disease?
For Crohn, think of a fat granny and an old crone skipping down a cobblestone road away from the wreck (rectal bleeding)
ULCCCERS
Ulcers, Large bowel, Continuous, Colorectal carcinoma, Crypt abscesses, Extend proximally, Red diarrhea, Sclerosing cholangitis
