Gastroenterology Flashcards
1
Q
Why do you see fat accumulation in alcoholic hepatic steatosis?
A
Decreased fatty acid oxidation since alcohol provides NADH from metabolism by alcohol and aldehyde DH
2
Q
What is the histology of carcinoid tumors?
A
Nests/sheets of cells with round/oval nuclei and eosinophilic cytoplasm; very uniform looking
3
Q
Increased gastric acid causes an ulcer where?
A
Duodenum!!!
4
Q
When do you get gastric ulcer?
A
When H. pylori destroys the epithelial lining of stomach from ammonia production
5
Q
What looks like a velvety cauliflower mass?
A
Villous adenomas
6
Q
What is a polyp symptom specific for villous adenoma?
A
Secretory diarrhea (due to large amounts of mucus production)
7
Q
Person ingests 13C labeled urea and then breath out 13C labeled CO2. What does this mean?
A
They have an H. Pylori infection. It is urease positive so it breaks down urea and the CO2 crosses into the blood and breathed out.
8
Q
Why do you get fistulas and strictures in Crohn’s?
A
Transmural inflammation
9
Q
What does Boerhaave present with?
A
Pleural effusion, retrosternal chest pain, left pneumothorax
10
Q
What does Mallory Weiss present with?
A
Hematemesis after vomiting lots
11
Q
What does stomach adenocarcinoma present with?
A
Virchow node (enlarged left supraclavicular node)
12
Q
What is the embryonic tissue origin of the spleen?
A
Mesodermal
13
Q
What is the pertechnetate scan for?
A
Meckel’s diverticulum
14
Q
What is Trousseau Syndrome?
A
Redness and palpable purpura on extremities (migratory thrombophlebitis)
15
Q
In what setting do you see Trosseau syndrome?
A
Pancreatic adenocarcinoma
16
Q
What is courvoisier sign?
A
Obstructive jaundice with palpable nontender gallbladder? Seen in pancreatic adenocarcinoma
17
Q
What do exclusively beast fed infants require?
A
Vitamin D supplementation
18
Q
What is the function of Niacin?
A
Inhibits VLDL synthesis and lipolysis
19
Q
What acid-base thing do you see with vomiting?
A
Metabolic alkalosis
20
Q
What would you get if on parenteral nutrition?
A
Gallstones due to lack of enteral stimulation secondary to decreased CCK
21
Q
What is the pathology of PBC?
A
Granulomatous bile duct destruction and lymphocyte portal duct infiltrate
22
Q
What does the pathology of PBC look similar to?
A
Graft vs Host Disease (GVHD)
23
Q
Why do you get gallstones in Crohn’s?
A
Impaired bile acid absorption which causes impaired fatty acid absorption. Calcium binds to it forming soap complexes and gets excreted in feces.
24
Q
Why do you get kidney stones in Crohn’s?
A
Less calcium in gut lumen to bind to oxalate since it is binding unabsorbed lipids instead
25
Which stomach artery is most susceptible to ischemia?
Short gastric because of lack of anastamoses
26
A jejunal ulcer is most likely due to what?
Gastrinoma
27
In what setting do you see mallory bodies?
Alcoholic Hepatitis
28
What are you at risk for if exposed to vinyl chloride and arsenic?
Liver angiosarcoma
29
Where is phosphatidylcholine found?
In bile acids
30
Which organ in the abdomen is least likely to get infarct?
Liver (due to dual blood supply; also has accessory supply from inferior phrenic, intercostals)
31
In what situation would you see a liver infarct?
Liver transplant since anastamoses are cut
32
What is a major effect of fibrates?
Decrease triglycerides
33
Posterior duodenal ulcers are most likely to cause bleeding from what?
Gastroduodenal artery
34
Anterior vs posterior duodenal ulcers are more prone to?
Anterior: perforation
Posterior: hemorrhage
35
Where is the duodenal bulb?
Right after the pylorus
36
How far to gastric erosions extend?
Into the muscularis externa but not all the way through (destroys gastric pits and glands)
37
Where are gastric pits?
In the mucosa
38
Where are gastric glands?
In the lamina propria
39
How far to gastric ulcers extend?
Submucosa
40
What causes acute mesenteric ischemia?
Atherosclerosis of mesenteric arteries (similar to angina)
41
What does acute mesenteric ischemia present with?
Epigastric post prandial pain
42
How do you differentiate acute mesenteric ischemia and peptic ulcer disease?
Peptic ulcer disease resolves w/ antacids and is not aw/ atherosclerosis
43
Cystic Fibrosis patient with acute pancreatitis is likely to be infected with what?
Pseudomonas
44
What does acute hepatitis present with?
Fever, nausea, anorexia, RUQ pain, bilirubinuria
45
What does acute hepatitis histology look like?
Ballooning, infiltrate, councilman bodies (eosinophilic globule in liver due to apoptosis)
46
Can conjugated bilirubin be excreted into the urine?
Yes because it is water soluble and doesn't need to bind to albumin
47
What would yo see on a radionuclide biliary scan during cholecystitis?
Nothing (failed visualization)
48
What do you see in the liver for sarcoidosis?
Scattered granulomas with Schauman and Asteroid bodies
49
What is a common complication of UC and how do you diagnose it?
Toxic megacolon. Diagnose by X-ray (colonoscopy and barium enema are contraindicated)
50
What causes autodigestion of pancreas?
Trypsin
51
How do right sided colon cancers present?
Fatigue, weight loss, iron deficiency anemia from bleeding
52
What is acalculous cholecystitis?
Inflammation of gallbladder without presence of stones. From ischemia
53
What is ectopy?
Structure/organ not in its usual place (Ex: Meckel's Diverticulum)
54
What enzyme is colonic adenocarcinoma linked to and what can you use to block it?
COX2 (use aspirin)
55
Where do anal tears occur?
Distal midline posterior to dentate line
56
Where do you see dermatitis herpetiformis?
On the butt's and extensor surfaces of adults?
57
Where do you see eczema (atopic dermatitis)
Rash on trunk aw/ food (differentiate from dermatitis herpetiformis which is on butt and extensor surfaces)
58
How does PBC commonly present?
Caucasian female with history of extreme pruritus now getting xanthelesma and pale stool
59
How is copper normally excreted?
In bile (absorbed in the GI tract then carried by albumin to liver then bound to ceruplasmin and excreted through bile)
60
What does alpha amanitin do?
It is from mushrooms and it inhibits RNA Pol II preventing mRNA synthesis. Toxic to hepatocytes, GI tract, PCT cells.
61
What causes mallory weiss tears?
Increased intraabdominal pressure that causes retching?
62
What causes esophagitis in HIV patients?
CMV, HSV, candida
63
If you undergo gastric resection, what specific nutrient do you need?
Vitamin B12
64
How do you diagnose Hirschsprung's Disease?
Sample the submucosa of the narrowed part
65
Lynch/HNPCC and sporadic colon adenocarcinoma are where?
Lynch/HNPCC: right
| Sporadic: left
66
What is a major toxicity of Omeprazole?
Hip fracture from decreased Ca absorption
67
What is colitis associated carcinoma?
Progresses from fat and non-polypoid dysplasia; has mucinous nad signet rings; affects younger patients
68
What mutation is colitis associated carcinoma associated with?
Early: p53
Late: APC
69
Where do you see colitis associated carcinoma?
Proximal colon but can be multifocal
70
How do you diagnose malabsorption?
Stool test to look for fat
71
When do you see thin curvilinear lines of lucency (pneumatosis intestinalis)?
Necrotizing enterocolitis (bacterial invasion and ischemic necrosis o bowel wall see in premies and when enteral feeding began)
72
What is gallstone ileus?
Fistula between gallbladder and small intestine leading to gallstone passing through small intestine and getting stuck at ileocecal valve?
73
What causes air int he gallbladder and biliary tree?
Gallstone ileus (fistula between GB and SI)
74
How does HBV cause hepatocellular carcinoma?
HBV integration into host genome
75
What is acarbose/miglitol?
Glucosidase inhibitor that prevents hydrolysis of disaccharides into monosaccharides so they can't be absorbed
76
Side effects of Acarbose/Miglitol
Flatulence, bloating
77
Ulcer in the distal duodenum is due to what?
Gastrinoma (Zollinger - Ellison)
78
What should you neonatal hepatitis make you suspicous for?
A1AT Deficiency
79
What does newborn with projectile nonbilious vomiting have?
Pyloric stenosis
80
What does newborn with projectile bilious vomiting have?
Volvulus
81
What happens if caudal fold fails to close?
Bladder exstrophy
82
What is an H-type TEF?
Pure TEF where there is a fistula alone
83
What does the splenorenal ligament contain?
Splenic artery and vein, tail of pancreas
84
Where are plicae circulares not located?
Duodenum
85
Where do peyers patches begin?
Ileum
86
Where does inferior epigastric come off?
External iliac
87
Where does superior epigastric come off?
Internal thoracic/mammary
88
What does the femoral sheath not contain?
Femoral nerve
89
Which hernia most likely to be incarcerated?
Femoral
90
Phenylalanine and tryptophan are potent stimulators of what?
Gastrin
91
What is a motilin receptor agonist?
Erythromycin
92
What does VIP do?
Increases intestinal water and electrolyte secretion, relaxes smooth muscle and sphincters
93
What neurotransmitter is used to stimulate G cells?
GRP
94
What test do you to distinguish GI mucosal damage from other causes of malabsorption?
D-Xylose test
95
What type of cancer does alcohol cause in the esophagus?
Squamous cell
96
What causes a cushing's ulcer?
Increased vagal stimulation leading to increased acid production
97
What causes a curling ulcer?
Decreased plasma volume causing gastric sloughing
98
If gastric ulcer perforates what artery bleeds?
Left gastric
99
What does abetalipoproteinemia present with?
Night blindness, acanthocytes, ataxia, steatorrhea, FTT
100
When do you see air in the bladder?
When diverticula perforate and cause colovesical fistula
101
Where do zenker's diverticulum occur?
At kilian triangle between thrypharyngeal and cricopharyngeal parts of inferior pharyngeal constrictor
102
What is angiodysplasia?
Tortuous dilation of vessels in cecum, terminal ileum, ascending colon, Can cause hematochezia
103
Why does aspirin cause reye's?
Decreases beta oxidatoin by reversible inhibition of mitochondrial enzyme
104
Can you biopsy a cavernous hemangioma?
No because it has a risk of hemorrhaging
105
What is hepatic adenoma?
Benign liver tumor related to oral contraceptive or anabolic steroid use. May regress sponataneously or rupture
106
What can you use to treat crigler-najjar?
Phenobarbital (increases liver enzyme synthesis)
107
What do you see on histology for pancreatic adenocarcinoma?
Disorganized glandular structure with cellular infiltration
108
What are the risk factors for pancreatic adenocarcinoma?
Tobacco, DM, Age >50, Jewish, African-American males, chronic pancreatitis
109
What are the side effects of cimetidine?
CYP inhibitor, antiadrogenic effects (impotence, gynecomastia, prolactin release etc), can cross BBB (headaches, confusion)
110
What are the side effects of PPI?
Pneumonia, osteoporosis, decreased Mg, increase risk for c. diff
111
What does ApoE do?
Remnant uptake
112
What does ApoC do?
LPL cofactor
113
Peptic ulcer where is least associated with malignancy?
Duodenum (gastric ones can progress to adenocarcinoma or MALToma)
114
What happens with the HFE gene is mutated?
Decreased hepicidin synthesis (less iron taken up from blood) and increased DMT1 (more iron uptake from GI lumen)
115
What will decrease in lactose challenge in someone with lactase deficiency?
Stool pH (bacteria ferment lactose to make fatty acids)
116
What is the D-xylose test for?
To check for malabsorption
117
How do you test for lactase deficiency?
Lactose is given and then seen if patient's blood glucose goes up and if they experience GI symptoms (bloating, diarrhea etc)
118
Gastric and pancreatic tissue in Meckel's is a type of: dysplasia, metaplasia, ecotpy?
Ectopy (tissue present in unusual locations because of embryonic maldevo)
119
What is the problem with abetalipoproteinemia?
MTP gene mutation (MTP ensures proper ApoB folding) so can't make chylomicrons, VLDL and absent cholesterol and triglycerides. Poor lipid absorption.
120
Diagnosis: weight loss, anorexia, jaundice, dark urine, pale stools, gallbladder enlarged but nontender?
Pancreatic adenocarcinoma. The gallbladder thing is Courvoisier's sign. That and obstructive jaundice indicate pancreas cancer.
121
What does the ventral pancreatic bud make?
Part of the head, main pancreatic duct, uncinate process
122
What causes bilious vomiting, absence of large segment of bowel, distal ileum winding around vascular stalk?
Vascular occlusion leading to intestinal atresia distal duodenum. If SMA obstructed, apple peel atresia --> blind proximal jejunum with absence of long length of small bowel due to ischemia and terminal ileum winding around ileocolic vessel.
123
What would you see hyperpigmented mouth lips, hands + abdominal discomfort?
Peutz-Jeghers
124
What is metaclopramide?
D2 antagonist, inc resting tone/contractility
Contraindicated in parkinson and small bowel obstruction
Interacts with digoxin and diabetic agents
Drowsiness, fatigue, restlessness, depression, nausea, diarrhea
125
Where are the GI stem cells ?
Crypts of Lieberkuhn
126
What drug can you use for weight loss in obese people?
Orlistat
127
If mass in rectum that has metastases to liver and abdominal nodes, what was the venous route?
Inferior mesenteric vein (that drains into portal vein into liver explaining the liver metastases; also upper rectum drains into internal iliac nodes)
Inferior rectal vein would drain into systemic circulation and cause lung metastases
128
What is a truncated form of ApoB100 and where is it produced?
ApoB48 produced in intestinal cells
ApoB100 in hepatocytes
129
What looks like edematous friable and granular mucosa with neutrophils in crypt lumina?
UC
Crypt abscesses = neutrophils in crypt lumina
130
What does Kaposi show on endoscopy?
Hemorrhagic nodules
131
What do you suspect if bilateral pitting lower extremity edema without cause (ie CHF, cirrhosis etc)?
IVC obstruction (also see abdominal wall collateral venous circulation - aka epigastric veins)
132
What is caput medusa from?
Anastamoses between paraumbilical and small epigastric veins
133
Where does copper deposit in the eye in Wilson's?
Descemet's membrane of CORNEA
134
Which type is associated with H. pylori? Intestinal or diffuse?
Intestinal
