USMLE GI Flashcards
Liver to anterior abdominal wall
Falciform
Liver to duodenum
Hepatoduodenal, portal triad: hepatic artery, portal vein, common bile duct
Liver to lesser curvature of stomach
Gastrohepatic, gastric arteries
Greater curvature and transverse colon
Gastrocolic, gastroepiploic arteries
Greater curvature and spleen
Gastrosplenic, small gastric arteries, left gastroepiploic vessels
Spleen to posterior abdominal wall
Splenorenal, splenic artery and vein
Octreotide is a _____ analog used to treat what 4 conditions?
Somatostatin Acromegaly Insulinoma Carcinoid syndrome Variceal bleeding
Gastrin - source
G cells
Gastrin - action (3)
Increase H+ secretion
Increase growth of gastric mucosa
Increase gastric motility
Gastrin - regulation (6)
Increased by: stomach distention, alkalinization, amino acids, peptides, vagal stimulation Decreased by pH
Somatostatin - source
D cells in pancreatic islets and GI mucosa
Somatostatin - action (4)
Decrease gastric acid and pepsinogen secretion
Decrease pancreatic and SI secretion
Decrease gallbladder contraction
Decrease insulin and glucagon secretion
Somatostatin - regulation (2)
Increased by acid
Decreased by vagal stimulation
CCK - source
I cells in duodenum, jejunum
CCK - action
Increase pancreatic secretion
Relax Sphincter of Oddi
Increase gallbladder contractions
Decrease gastric emptying
CCK - regulation
Increased by fatty acids and amino acids
Secretin - source
S cells (duodenum)
Secretin - action (3)
Increase pancreatic HCO3 secretion
Increase bile secretion
Decrease gastric acid secretion
Secretin - regulation
Increased by acid, fatty acids in lumen of duodenum
GIP (Gastric inhibitory peptide) - source
K cells (duodenum, jejunum)
GIP (Gastric inhibitory peptide) - action
Decrease H+ secretion
Increase insulin release
GIP (Gastric inhibitory peptide) - regulation
Increased by fatty acids, amino acids, oral glucose
Motilin - source
Small intestine
Motilin - action
Produces migrating motor complexes to stimulate intestinal peristalsis
Motilin - reg
Increased in fasting state
What structure lies lateral to a femoral hernia?
Femoral vein
What artery is located posterior to the duodenal bulb?
Gastroduodenal artery
1 g of protein yields how many calories of energy?
4 cal
What vitamins do you need supplement a purely breastfed baby?
Vit D & K
Carcinoid tumour and other neuroendocrine tumours will be positive for what?
Chromogranin
Under what conditions will you see carcinoid syndrome from a carcinoid tumour
Metastases to liver due to first pass metabolism of serotonin
What is the histologic hallmark of ulcerative colitis?
Crypt abscesses with neutrophils
Risk of carcinoma in UC depends on what factors?
Extent (more = worse) and duration (>10 years) of involvement
What is the histologic hallmark of Crohn’s disease?
Noncaseating granulomas with lymphoid aggregates
What test do you need to dx Hirschsprung’s?
Rectal suction biopsy
What condition is Hirschprung’s classically associated with?
Down Syndrome
What are the complications of a diverticulum?
Rectal bleeding (hematochezia)
Diverticulitis
Fistula
Where in the colonic wall is particularly susceptible to diverticulum formation?
Where vasa recta perforate the muscularis propria
What protects against the Adenoma-carcinoma sequence?
Aspirin, by blocking COX
What increases the risk of progression from colonic adenoma to carcinoma?
- > 2cm
- Sessile growth (flat)
- Villous histology
What cancers are colorectal carcinomas associated with?
Endometrial
Ovarian
Skin
What is CEA useful for in Colon CA?
Treatment response and recurrence; NOT screening
What is the first enzyme that is activated in acute pancreatitis?
Trypsin
What is a complication of an annular pancreas?
Duodenal obstruction
What do you think of when you see a thin elderly person with new onset T2DM?
Pancreatic cancer in the body/tail.
What biomarker is associated with pancreatic cancer?
CA 19-9 (more specific than CEA)
What do you think of when you see an elderly woman with new onset cholecystitis?
Gallbladder carcinoma
What causes dark urine in gallbladder problems?
Excessive urubilinogen
What is the mechanism by which phototx resolves physiologic neonatal jaundice?
Converts unconjugated bilirubin to a water-soluble form
A surgeon is operating and finds a pitch black liver. What condition does this patient have?
Dubin Johnson Syndrome
What do you worry about in a pregnant woman with Hep E?
Fulminant hepatitis
What cell mediates fibrosis in cirrhosis?
Stellate cell
In what condition will you find Mallory bodies and what do they contain?
Alcoholic hepatitis, contain damaged keratin filaments
What is the mechanism of injury in hemochromatosis?
Free radical generation
What marker do you look for in primary biliary cirrhosis?
Anti-mitochondrial antibody
What is damaged in Reye syndrome?
Hepatic mitochondria
Hepatic adenomas are related to what drug use?
OCP, will go away with cessation
What tumour marker is used in hepatocellular carcinoma?
Alpha-fetoprotein
Bloody diarrhea from E. Coli produces a substance that inhibits protein synthesis. What is this substance and what is it most similar to?
Shiga-like toxins, shigella.
Prolonged cholestasis can lead to poor absorption of fat soluble vitamins, leading to what condition?
Osteomalacia
Direct vs indirect inguinal hernia?
Medial and lateral to inferior epigastric artery
What organ is derived from mesoderm but supplied by foregut vessel?
Spleen
What hematologic side effect do you see with alcoholism?
Macrocytosis
Cecum stuck to RUQ. What happened?
Midgut failed to rotate around SMA
What is another name for lactose?
Galactosyl B-1,4-glucose
PAS = stain for what?
Glycoprotein
Recurrent pseudomonas infections =?
CF
Cancer in 3rd part of duodenum invades what structure?
SMA
