Gastrointestinal Flashcards
Organism associated with Whipple disease
Organism associated with Whipple disease: Tropheryma whippelii (+); “Foamy Whipped cream in a CAN”. Foamy (PAS-positive) macrophages; Cardiac symptoms; Arthralgias; Neurologic symptoms.
Process by which B12 is absorbed
- (stomach) Pepsin releases B12
- (stomach) B12 binds to R-binders
- (duodenum) R-binder-B12 complex broken down in duodenum by pancreatic proteases
- (duodenum) unbound B12 binds IF
- IF-B12 complex binds to IF-specific receptors on cells of the Terminal Ileum
- B12 transverses plasma membranes of mucosal cell
- picked up by plasma protein transcobalamin II
Pleomorphic adenoma
1 most common overall is Pleomorphic adenoma - benign, epithelial and mesenchymal, about 50% of all salivary gland tumors are this type.
2 most common benign tumor of salivary gland
2 most common benign tumor is Warthin’s tumor - heterotopic salivary gland tissue trapped in a lymph node, surrounded by lymphatic tissue.
2 most common tumor overall salivary gland tumor
mucoepidermoid carcinoma -#1 malignant
$ 3 Arteries off celiac
Main blood supply of the stomach: common hepatic, splenic, left gastric
$ Primary biliary cirrhosis
Autoimmune reaction with lymphocyte infiltrate and granulomas. 90% are middle aged females, Pruritis w/o Jaundice.
- 90% ↑ serum mitochondrial antibodies, including IgM.
- Tx: Ursodiol ↓ liver synthesis of cholesterol ↓ bile stone development. Definitive Tx: liver transplant
$ Primary sclerosing cholangitis
Unknown cause of “onion skin” bile duct fibrosis with alternating strictures and dilation with “beading”
- (1)Beads on a string appearance on ERCP.
- (2) Men around 40.
- (3) 60% have positive p-ANCA. Also an association with
- (4) Ulcerative colitis, and
- (5) Cholangiocarcinoma.
- Definitive Tx: liver transplant
2 nervous tissue bundles that run through the GIT
Submucosal Nerve Plexus (Meissner’s) running through the Submucosa (secretions).
Myenteric nerve plexus (Auerbach’s) running through outer layer of the muscularis externa (Motility and MMCs).
4 off common hepatic
- Right Gastro-omental artery,
- Anterior superior pancreaticoduodenal arteries (supplies proximal duodenum),
- Hepatic artery proper,
- Right Gastric artery.
Achalasia is a results from
loss of myenteric or Auerbach’s plexus ® LES is unable to relax; Diagnosis - barium swallow (stricture of LES looks like bird’s beak), manometry - device that measures pressure in esophagus.
Alcoholic hepatitis histologically
Mallory bodies - intracytoplasmic eosinophilic inclusions; Hepatocytes - Necrotic and swollen.
Antibodies to help make the diagnosis of autoimmune hepatitis
- ANA (+)
- Anti-smooth muscle antibody (+)
- Anti-liver-kidney microsomal antibody (+)
- Anti-mitochondrial antibody (-)
Arterial branches off the common hepatic artery
- Gastroduodenal artery ® Right Gastro-omental artery + Superior pancreaticoduodenal artery;
- Right gastric artery;
- Hepatic artery proper ® Left hepatic and right hepatic.
Atropine will inhibit the release of gastrin b/
Atropine will inhibit the release of gastrin b/c: Vagus nerve stimulates G cells using gastrin-releasing peptide; Atropine - reduces vagal stimulation at parietal cells and ECL cells. Vagal stimulation of G cells is unaffected as GRP is used, not ACh.
Biliary obstruction Intrahepatic vs extrahepatic causes
Intrahepatic: Primary biliary cirrhosis; Sclerosing cholangitis; Drugs (Chlorpromazine and arsenic);
Extrahepatic: Pancreatic neoplasm; Choledocholithiasis (gallstone in common bile duct); pancreatitis; cholangiocarcinoma.
Budd-Chiari syndrome
Occlusion of the IVC or hepatic veins. Associated with Polycythemia vera; Pregnancy; Hepatocellular carcinoma. Hepatomegaly, ascites, abdominal pain, possible varices and visible abdominal and back veins, Absence of JVD. Eventual liver failure due to occlusion of IVC or hepatic veins with centrolobular congestion and necrosis.
Cholangitis
Cholecystitis
Choledocholithiasis
Cholelithiasis
- Cholangitis - Inflammation/infection of biliary tree (Charcot’s/Reynolds)
- Cholecystitis - Inflammation/infection of the gallbladder
- Choledocholithiasis - Gallstones in the bile ducts (usually common bile duct)
- Cholelithiasis - Gallstones
Classic symptoms of carcinoid syndrome
“BFDR” Bronchospasm (wheezing); Flushing; Diarrhea (less specific); Right sided valvular disease symptoms (edema or ascites).
Classic triad in hemochromatosis
micronodular cirrhosis, DM, skin pigmentation. Labs - ↑ ferritin, ↑ serum iron, ↓ TIBC -> ↑ transferrin saturation. Tx: Phlebotomy; Deferoxamine.
Cocktail of medications commonly taken by patients suffering from severe cirrhosis
Lactulose (encephalopathy); Vitamin K (maximize clotting potential); Diuretics (prevent ascites and edema); β-blockers (bleeding esophageal varices) “LV DB” needs meds for liver cirrhosis”
Colon Polyps
Tubular adenomas (adenomatous polyps); Tubular villous adenomas; Villous adenomas. All are precancerous, but villous is most villainous! All 3 of these NEED to be removed 100% of the time! Need to be analyzed for carcinoma in-situ.
Common causes of SBO
1 - Adhesions, Bulge/hernia, Cancer/tumor.
Difference between primary biliary cirrhosis and primary sclerosing cholangitis
Primary Biliary Cirrhosis: Positive AMA; Middle-aged females; Autoimmune disease - CREST scleroderma.
Primary Sclerosing Cholangitis: Unknown etiology; Positive pANCA; Males over 40; UC and cholangiocarcinoma; ERCP: beading and stricturing
Disorders w/ excess gastrin
Zollinger Ellison syndrome; Tx is PPIs +/- octreotide (if tumor has octreotide receptors).
Drugs that inhibit acetylcholinesterase
Echothiophate - glaucoma;
Edrophonium - diagnose MG;
Neostigmine - ileus, urine retention, MG;
Physostigmine - glaucoma;
Pyridostigmine (longer acting) - MG.
Enzyme responsible for the conjugation of bilirubin
Fate of bilirubin after it is conjugated and secreted into GI tract
UDP-Glucuronyl Transferase. (upregulated by phenobarbital)
(1) Converted to urobilinogen (acted on by gut bacteria) (2) Some is excreted and (3) some is reabsorbed.
GI pathology with Down Syndrome
Celiac disease; Hirschprung disease; Annular pancreas; Duodenal atresia. (CHAD)
Hexokinase and glucokinase differ in Location, Kinetics, Insulin
Hexokinase is everywhere ↓Vmax ↓Km and Glucokinase is in liver and Pancreas (β cells) with ↑Vmax ↑Km. Insulin does NOT induce hexokinase, Does induce glucokinase.
HIV meds pancreatitis
Ritonavir and NRTIs like Didanosine, Stavudine, Zalcitabine;
Rash - NNRTIs like Nevirapine, Delavirdine, Efavirenz and Abacavir causes a hypersensitivity.
Peripheral neuropathy - Didanosine, Stavudine, Zalcitabine.
In a patient with elevated alkaline phosphatase, what other enzymes would indicate liver disease?
an elevation in AST, ALT, GGT would direct me to a diagnosis of liver disease.
Mechanism by which aspirin can cause Reye syndrome
↓ β-oxidation occurs because metabolites of aspirin inhibit mitochondrial enzyme.
Medications for the treatment of chronic hepatitis B and C are
interferon alpha (Chronic hepatitis B and C); Ribavirin (chronic hepatitis C)
Names of diverticula found in esophagus based on location are
Zenker - immediately above the UES;
Traction - Near the midpoint of esophagus;
Epiphrenic - immediately above LES.
One of the most common causes of GI bleeding in the elderly (other than colon cancer)
One of the most common causes of GI bleeding in the elderly (other than colon cancer) is Angiodysplasia (volvulus, ischemic colitis also common in elderly)
Pleomorphic adenoma histology
(#1 benign). Histology: Epithelial and mesenchymal differentiation. 50% of salivary gland tumors are pleomorphic.
PPI MOA
** H+/K+ ATPase** in stomach parietal cells: Omeprazole, lansoprazole, pantoprazole, esomeprazole.
Progastric Hormones
Inhibitory Gastric Acid Hormones
Drugs that regulate Gastric Acid Secretion
Progastric Hormones: Histamine; Acetylcholine; Gastrin.
Inhibitory Gastric Acid Hormones: Prostaglandins; Somatostatin; Secretin; GIP (gastric inhibitory peptide).
Drugs that regulate Gastric Acid Secretion: PPIs; H2 blockers; Antimuscarinic drugs (Atropine).
Receptors on gastric parietal cells regulate acid secretion
H2 Histamine receptor is most important; CCKB receptors (responds to gastrin); M3 (responds to Ach); Prostaglandin receptors; Somatostatin receptors.
Risk factors for development of hepatocellular carcinoma
HBV, HCV, Wilson’s disease, hemochromatosis, α1-antitrypsin deficiency, alcoholic cirrhosis, carcinogens (aflatoxin from Aspergillus), Hepatic adenoma.
Reynold’s pentad
cholangitis is: Jaundice, Fever, RUQ pain, Hypotension (shock) and altered mental status.
Risk factors for the development of cholesterol gallstones
FFFF: Female, Fat, Fertile (pregnant), Forty.
Warthin’s tumor
Second most common benign cystic tumor with a double layer of columnar epithelium around the cyst. Stroma of the tumor is lymphoid. Like a lymph node and can even form germinal centers
Serum antibodies associated with celiac sprue
Autoantibodies to gluten (gliadin) and tissue transglutaminase
Organisms most responsible for Sialodenitis
S. Aureus and S. Viridans, S. Mutans.
Signs of portal hypertension
Esophageal varices ® Hematemesis, Melena. Peptic ulcer ® Melena; Splenomegaly; Caput medusae, ascites; Portal hypertensive gastropathy; Hemorrhoids.
The most common #1 malignant salivary gland tumor (and #2 most common overall behind pleomorphic adenoma)
mucoepidermoid carcinoma
Treatment for celiac sprue
Gluten free diet; Avoid rye, wheat, and barley
Underlying problem in Wilson disease
Impaired copper excretion, Body does not put copper into bile-> failure of copper to enter circulation as ceruloplasmin.
Characteristics -> Asterixis; Basal ganglia degeneration (Parkinsonian symptoms); ↓ ceruloplasm; Cirrhosis; Kayser-Fleischer rings; Copper accumulation; Hepatocellular carcinoma; Dementia; Dyskinesia; Dysarthria Tx: Penicillamine
Classic presentation of diverticulosis
Usually asymptomatic; ± Painless rectal bleeding; ± Vague LLQ discomfort
After loss of his job, a 35-year-old man has diarrhea and hematochezia. Intestinal biopsy shows transmural inflammation. Diagnosis ® 35yo male + diarrhea + hematochezia + Stress (loss job) + TRANSMURAL INFLAMMATION
Crohn’s Disease
Adult Anatomy of the liver
Zone 1 - Hepatic artery(↑O2), hepatic vein, bile ductules affected most by viral hepatitis;
Zone 3 - Central vein (affected most by ischemia) Contain cytochrome p450 (most affected by alcoholic hepatitis).
Diverticulitis Tx
Metronidazole (for anaerobes) + TMP-SMX, or M + levofloxacin, or M + ciprofloxacin.
Dysbiosis
imbalance of the enterobacteriaceae species
Enterobacteriaceae
All are Gram (-); facultative anaerobe; ferment sugar into lactic acid (if too much, can cause lactic acidosis). Normal gut flora. #1 Bacteroides fragilis - Most abundant organism in the large intestine. #2 E. coli - second most abundant organism in the large intestine. Family also includes: Proteus mirabilis; Proteus vulgaris; Salmonella; Shigella; Klebsiella pneumoniae.
Etiologies of acute pancreatitis
GET SMASHHED - Gallstones, Ethanol, Trauma (NFL), Steroids, Mumps, Autoimmune diseases, Scorpion sting, Hypercalcemia/Hypertriglyceridemia >1000 (milk/tricycle at HH), ERCP (Endoscopic retrograde cholangiopancreatogram), Drugs (sulfa + HIV drugs) (NRTI’s didanosine, zalcitabine, stavudine, Ritonavir (PI).
Fundamental problem in Hirschprung disease
failure of neural crest cell migration to colon ® missing enteric ganglia/enteric nervous plexus.
H. pylori treatment
PPI; Clarithromycin; Amoxicillin or (if allergic to amoxicillin) metronidazole.
HBcAg
Hepatitis B core antigen = New disease
HBeAg
Hepatitis B envelope antigen - **very High degree of contagiousness **
HBsAg
hepatitis B surface antigen = Active disease!
Intestinal disorder common in NICU to premature babies that receive oral feds too soon
Necrotizing Enterocolitis
Lab abnormalities with cirrhosis
↑AST/ALT but may not if damaged all of liver cells. ↑GTT ↓platelets ↑PT; ↓lipids (LDL, HDL); ↑ammonia
Metoclopramide (Reglan)
antagonist at the D2-receptor and agonist at 5-HT4 receptors. Used for diabetic and post-surgical gastroparesis (slight degree of gastroparalysis).
Ondansetron and Granisetron
(-setron) are the 5-HT3 antagonists used for anti-emetic purposes. 5-HT1 agonists cause vasoconstriction used to treat headaches. Serotonin antagonists cause vasodilation which create headaches. Too much serotonin (carcinoid syndrome) - diarrhea; Too little serotonin - constipation.
Osler-Weber-Rendu Syndrome
AD disorder; Telangiectasias can cause Aneurysms, AVMs - high output heart failure; Nose bleeds, GI bleeds, Iron deficiency anemia, Visceral bleeds (lung, liver).
most common location of salivary gland tumors
Parotid gland
