GI Flashcards
What is in the portal triad (hepatoduodenal ligament)?
Proper hepatic artery
Portal vein
Common bile duct
What connects the liver to the abdominal wall? What fetal structure is it derived from?
Falciform ligament; Ligamentum teres hepatis (fetal umbilical vein)
What is the difference between the submucosal nerve plexus (Meissner) and the muscularis externa (Auerbach)?
Meissner - secretory
Auerbach - contractions
Where are Brunner’s glands located?
Submucosa of the duodenum
Where are Plicae circulares found? Where are Peyer patches found?
Plicae Circulares - Jejunum
Peyer Patch - Lamina propria/submucosa of Ileum
Where are the largest numbers of goblet cells found in the small intestine?
Ileum
What nodes drain the rectum above the pectinate line?
Below the pectinate line?
Above: Lymphatic drainage to deep nodes
Below: Lymphatic drainage to superficial inguinal nodes
What are the differences between internal and external hemorrhoids?
Internal Hemorrhoids: Above the pectinate line and not painful (visceral innervation)
External Hemorrhoids: Below the pectinate line and painful (somatic innervation - pudendal nerve)
What distinguishes Zone 3 of the liver from the other zones?
Affected 1st by ischemia
Contains cytochrome P-450 system
Most sensitive to metabolic toxins
Site of alcoholic hepatitis
GIP
Source:
Action: (Endocrine and Exocrine)
Source: K cells (duodenum and jejunum)
Action: Endocrine (Increases insulin release); Exocrine (Decreases gastric H+ secretion)
Why is an oral glucose load used more rapidly than the equivalent given by IV?
Due to GIP secretion (Increased by fatty acids, amino acids, and oral glucose)
Vasoactive Intestinal polypeptide
Source:
Action:
Source: Parasympathetic ganglia in sphincters, gallbladders, small intestine
Action: Increased water and electrolyte secretion; Increased relaxation of intestinal smooth muscle and sphincters
How does Atropine Affect GI function?
Atropine is an anticholinergic drug that inhibits parasympathetic action on Gastric parietal cells - Decreased acid secretion
What things inhibit the gastric parietal cell?
Atropine (blocks parasympathetic activation) Proton pump inhibitors Prostaglandins/Misoprostol Somatostatin H2 blockers
What is conjugated to bile salt to make it water soluble?
Glycine or taurine
What catalyzes the rate limiting step of bile synthesis?
Cholesterol 7alpha-hydroxylase
What is CREST syndrome?
Calcinosis Raynauds phenomenon Esophageal dysmotility Sclerodactyly Telangectasias - associated with anti-centromere antibodies
What is the difference between a Curling ulcer and a Cushing ulcer?
Curling ulcer: Decreased plasma volume leads to sloughing of gastric mucosa (Burns)
Cushing ulcer: Increased vagal stimulation leads to increased ACh and thus increased acid (H+) production
What is the difference between type A and type B gastritis?
Type A: Fundus/body - autoimmune
Type B: Antrum - H. pylori
What is Menetrier disease?
Gastric hypertrophy with protein loss, parietal cell atrophy, and increased mucous cells (Rugae look like brain gyri)
What is a Virchow node? What is a Krukenberg tumor? Sister Mary Joseph nodule?
Virchow node: Involvement of left supraclavicular node by metastasis from stomach
Krukenberg tumor: Bilateral metastases to ovaries - signet ring cells
SMJ nodule: Subcutaneous periumbilical metastasis
Which hemorrhage affects the left gastric artery? Which affects the gastroduodenal artery?
Ruptured gastric ulcer on lesser curvature of stomach - LGA
Posterior wall of the duodenum - GDA
What genetics are associated with Celiac Sprue?
HLA-DQ2 and HLA-DQ8
What are the differences in Th response to Ulcerative colitis and Crohn’s disease?
Ulcerative colitis: Th2 mediated response (Crypt abscesses and ulcers)
Crohn’s disease: Th1 mediated response (Noncaseating granulomas)
What is Peutz-Jeghers syndrome?
Autosomal dominant syndrome featuring multiple nonmalignant hamartomas throughout the GI tract - hyperpigmented mouth, lips, hands genitalia
Describe the following precursors to colorectal cancer:
Gardner syndrome:
Turcot syndrome:
Hereditary nonpolyposis colorectal cancer (Lynch syndrome):
Gardner: FAP + osseous and soft tissue tumors
Turcot syndrome: FAP + malignant CNS tumor (TURcot = TURban)
HNPCC/Lynch syndrome: Mutation of DNA mismatch repair genes (80% progress to CRC and proximal colon is always involved)
What are the ALT and AST findings in…
Alcoholic hepatitis
Viral hepatitis
Alcoholic hepatitis: AST>ALT (2:1)
Viral hepatitis: ALT>AST
In what disease is there a decrease in ceruloplasmin?
Wilson Disease
What is the serum marker for both Acute pancreatitis and Mumps? What marker is specific for acute pancreatitis?
Amylase; Lipase
What serum marker is increased in various liver and biliary diseases but not in bone disease?
gamma-glutamyl transpeptidase (GGT)
How are serum markers different between NAFLD and alcoholic hepatitis?
In NAFLD: ALT>AST
How is hepatic encephalopathy treated?
Lactulose (for increased NH4+); Low protein diet; Rifaximin (kills intestinal bacteria)
What serum marker is associated with HCC?
Increased alpha-fetoprotein
What malignant tumor of endothelial origin is associated with exposure to arsenic and vinyl chloride?
Angiosarcoma
Whipple disease and alpha-1 antitrypsin deficiency both are positive in what?
PAS positive
How is Wilson Disease treated?
Penicillamine or trientine
Why doesn’t hemochromatosis cause pancreatic insufficiency? What mutations are associated with hemochromatosis?
The iron deposits in alpha cells of the pancreas and not beta cells; HFE gene (transferrin binding) and C282Y
What are some causes of acute pancreatitis? (GET SMASHED)
Gallstones Ethanol Trauma Steroids Mumps Autoimmune disease Scorpion sting Hypercalcemia (Increases pancreatic enzyme release)/Hypertriglyceridemia ERCP Drugs (Sulfa drugs)
What tumor marker is associated with Pancreatic adenocarcinoma? Where is the tumor most commonly found?
CA-19-9 (also CEA although less specific)
Pancreatic head
What is migratory thrombophlebitis (associated with pancreatic adenocarcinoma)?
Redness and tenderness on palpation of extremities (Trousseau syndrome)
What are the retroperitoneal structures?
SADPUCKER Suprarenal Aorta (and IVC) Duodenum (2nd through 4th parts) Pancreas Ureters (Descending and Ascending) Colon Kidneys Esophagus (lower 2/3) Rectum (partially)
What is the innervation of the foregut and midgut?
What is the innervation of the hindgut?
Foregut and midgut: Vagus nerve
Hindgut: Pelvic nerve
What anastamoses can compensate for blocked branches of the abdominal aorta?
1) Subclavian → Internal thoracic → Superior epigastric → Inferior epigastric → External iliac
2) Celiac trunk → Superior pancreaticoduodenal → Inferior pancraticoduodenal → SMA
3) SMA → Middle colic → Left colic → IMA
4) IMA → Superior rectal → middle/inferior rectal → Internal iliac
Lymphatic drainage occurs in the ______ __ _____
Space of Disse
What is the arrangment of femoral region components from lateral to medial?
NAVL
Nerve (not in the sheath) → Artery → Vein (venous near the penis) → Lymphatics
Indirect inguinal hernia
More common in:
Location:
Cause:
More common in: male infants
Location: enters internal inguinal ring lateral to inferior epigastric artery
Cause: failure of processus vaginalis to close
Direct inguinal hernia
More common in:
Location:
Cause:
More common in: Adult males
Location: Bulges through hesselbach’s triangle medial to inferior epigastric vessels
Cause: Weakness of transveralis fascia
Which amino acids are potent stimulators of gastrin secretion?
Phenylalanine and tryptophan
Through what mechanism does CCK cause pancreatic secretion?
Acts on neural muscarinic pathways
Through what mechanism does gastric increase gastric acid secretion (mostly)?
Gastrin effects enterochromaffin-like (ECL) cells leading to histamine release which causes acid release from parietal cells
How are glucose and galactose absorbed in the intestine? What is this dependent on?
Glucose and galactose are taken up by SGLT1 in a Na+ dependent process
What are the salivary gland tumors and which is malignant?
Pleomorphic adenoma - painless, mobile mass, with chondromyxoid stroma and epithelium
Warthin tumor - benign cystic tumor with germinal centers
Mucoepidermoid carcinoma - most common malignant tumor
What is the difference between HSV esophagitis and CMV esophagitis?
HSV - punched-out ulcers
CMV - linear ulcers
“HSV punched CMV because he was straight”
What skin condition can be seen in stomach cancer?
Acanthosis nigricans
What type of malignancy is associated with celiac sprue?
T-cell lymphoma
Which malabsorption syndrome can cause night blindness?
Abetalipoproteinemia (along with failure to thrive, acanthocytosis, steatorrhea, and ataxia)
What is the location of a Zenker diverticulum?
Between the thyropharyngeal and cricopharyngeal parts of the inferior pharyngeal constrictor
What mutation is associated with Hirschsprung disease?
Mutations in the RET gene
What findings are associated with the following areas of colorectal cancer…
Ascending colon:
Descending colon:
Ascending colon: Exophytic mass, iron deficiency anemia, weight loss
Descending colon: Infiltrating mass, partial obstruction, colicky pain, hematochezia
Oral contraceptives can cause what kind of liver tumor?
Hepatic adenoma
Which gallbladder stones are radiolucent? Which are radiopaque?
Radiolucent: Cholesterol stones
Radiopaque: Pigment stones
