GI Flashcards

Question

hepatic abscess

Answer 1

developed countries - Staph (other bacteria) underdeveloped countries - Entamoeba histolytica (foodborne), echinococcus (parasites) - Entamoeba - from portal venous system methods - hematogenous spread - Staph - ascending cholangitis - gram negative enterics (E coli, Kleb), enterococci. Same group in direct invasion from a nearby source. - traumatic injury - mixed aerobic, anaerobic flora

Answer 2

ezetimibe - blocks intestinal cholesterol absorption - ADRs - elevated transaminases, diarrhea fish oil supplement (omega 3) - increase bile acid synthesis and increase gallbladder motility niacin - increases HDL (inhibits catabolism) and lowers TGs (inhibits VLDL secretion)

Answer 3

achalasia - reduced numbers of inhibitory ganglion cells in myenteric plexus (inhibitory neurons that contain NO and VIP) - decreased amplitude of peristalsis, incomplete relaxation at LES cricopharyngeal dysfunction - failure of this muscle to relax during swallowing (normally this muscle contracts to start peristalsis) - feels like food is stuck in your mouth diffuse esophageal spasm - periodic, uncoordinated contractions due to impaired inhibitor innervation of myenteric pelxus esophageal stricture - solid food dysphagia, occurs due to GERD (decreased tone at LES) - systemic sclerosis is similar - esophageal atrophy --> impaired motility, incompetent LES - histology - collagenous fibrosis

Answer 4

GE junction incompetence or sliding hiatal hernia risk factors - alcohol, tobacco, fatty diet, caffeine extraesophageal symptoms - nocturnal cough, adult onset asthma histology - basal zone hyperplasia, elongation of lamina propria papillae, eosinophils

Answer 5

commonly see with tetracyclines, KCl, and bisphosphonates, NSAIDs, Fe

Answer 6

calcinosis, raynaud, esophageal dysmotility, sclerodactyly, telangiectasia - limited variant - disease affects face, forearms, and fingers chronic autoimmune inflammation --> endothelial injury (fingertip ulcers), excessive fibroblast activation (fibrous replacement of lower esophagus --> esophageal dismotility, the esophageal body and the LES become atonic and DILATED)

Answer 7

due to drugs (sedatives, narcotics), diarrhea and electrolyte changes, increased nitrogen load (GI bleeding), infection, portosystemic shunting GI bleeding --> Hb, increased nitrogen delivery to the *gut* --> converted to ammonia --> enters portal vein (and ideally should be detoxified to urea) ammonia acc - affects brain --> increased inhibitory NT, impaired excitatory NT give lactulose - converted to acid by colonic bacteria, and traps NH3

Answer 8

indirect inguinal - infants - patent processus vaginalis - internal inguinal ring doesnt close - contents protrude through deep inguinal ring, travel LAT to inferior epigastric vessels - covered by all 3 spermatic fascial layers direct inguinal - older men, weakness of transversalis fascia - contents protude through Hesselbach trinagle - travels MED to inferior epigastric vessels - covered only by external spermatic fascia femoral - women - weakness of proximal femoral canal - travels inferior to inguinal ligament (the other two are above the inguinal ligament) - medial to femoral NAV

Answer 9

1) carrier-mediated uptake of bilirubin from blood 2) conjugation with glucuronic acid by UGT in the ER 3) biliary excretion of the now water-soluble bilirubin Crigler-Najjar, AR - lack of UGT - kernicterus = jaundice and neuro impairment Dubin-Johnson, AR - absence of biliary transport protein MRP2, used to dump bilirubin into bile - liver becomes dark pigmented, pts are otherwise asymptomatic Rotor, AR - asymptomatic conjugated bilirubinemia - due to defects in hepatic uptake and excretion of bilirubin pigments increased deconjugation of bile acids (aas are removed) - they are now less soluble, less able to form micelles and be reabsorbed bacterial enzymes also reduce bilirubin into urobilinogens

Answer 10

vestibular system - H1, M1 chemo - D2 - dopamine antagonists can cause GI upset GI - 5HT3 - GI irritation due to infections, chemo, distention --> increased serorotonin

Answer 11

monosaccharide - used to test for brush border absorptive function, independent of pancreatic function d-xylose absorption can also decrease with bacterial overgrowth of SI

Answer 12

opioids cause histamine release --> vasodilation of blood vessels constipation - slow gut motility also decrease parietal cell acid secretion indirectly increase somatostatin secretion from pancreas

Answer 13

susceptible to nonocclusive ischemia splenic flexure - SMA and IMA rectosigmoid junction - border between sigmoid artery and superior rectal artery (note the rectal also receives blood from branches of the internal iliac)

Answer 14

liver is the second most common site of mets (after LNs) hepatic adenoma - benign epithelial tumor, right lobe - associated with OCPs, steroids - can rupture and cause intra-abd hemorrhage hepatic angiosarcoma - PVC, arsenic, thorotrast - extremely aggresive hepatoblastoma - kids, associated with Beckwith-Wiedeman syndromes HCC - unifocal, multifocal, diffusely infiltrative cancer cholangiocarcinoma (poor prognosis) - tree=like mass that grows along the biliary system --> extensive hepatic mets - risk factors include sclerosing cholangitis, fibropolycystic liver disease, liver flukes

Answer 15

ligand binds to receptor tyrosine kinase --> --> Ras is active when bound to GTP --> MAPK - Ras has intrinsic GTPase activity

Answer 16

celiac trunk - foregut structures SMA - midgut IMA supplies hindgut derivatives rectum - internal iliac --> internal pudendal --> inferior rectal - internal iliac --> middle rectal (note - superior rectal comes from IMA)

Answer 17

non-keratinized squamous epithelium TEF - most common variant is proximal esophageal atresia and distal TEF, baby who drools and chokes on first feeding Zenker diverticulum -at esophageal-pharyngeal junction Mallory-Weiss tears - due to increased intraabdominal pressure, painful bleeding - hiatal hernias are a predisposing factor - blood loss is never life-threatening (esophageal varicies on the other hand can cause life-threatening bleeding, painless bleeding) Boerhaave syndrome - medical emergency esophageal varices - left gastric vein --> esophageal vein (- hemorrhoids - sup rectal --> mid and inf rectal) (-caput medusa - paraumbilical veins --> superficial and inf epigastric veins) - can also develop splenomegaly - can insert a TIPS (portal to hepatic vein shunt) ........................................................................................ CANCER: hematemesis and mets SCC - toxins (alcohol, tobacco, smoked foods), ((very hot food/beverages) - can also occur from achalasia or Plummer-Vinison syndrome - upper 2/3 adenocarcinoma - Barretts/Gerd, obesity, tobacco - lower 1/3

Answer 18

occurs in kids less than 2 years old - in older kids, look for a lead point (also associated with rotavirus vaccine) impaired venous return from invaginated segment of bowel --> ischemia and necrosis of intestinal most common occurs at ileocolic junction - small bowel invaginates into larger cecum barium enema is diagnostic and therapeutic, otherwise surgery

Answer 19

centrilobular necrosis

Answer 20

AD - mutation in LDL receptor gene | - liver LDL receptor - removes cholesterol-containing IDL and LDL particles

Answer 21

cleft lip and palate - facial prominences ``` apthous ulcer (agra phod, stress) - associated with Behcet syndrome - recurrent apthous ulcers, genital ulcers, and uveitis (due to IC vasculitis) ```

Answer 22

SNS and PSNS --> saliva is high in K+ and HCO3-, contains kallikrein (which makes bradykinin) parotid - mumps, stones (S. aureus infection) cancers 1) pleomorphic adenoma - cartilage + epithelium, rarely transforms into carcinoma (but if it does, facial nerve involvement) 2) Warthin tumor - papillary cystadenoma lymphomatosum (germinal center) 3) Mucoepidermoid carcinoma

Answer 23

chylomicrons - cholesterol and TG core surrounded by phospholipids and apoproteins --> uptaken into lacteals duodenum - Paneth cells that secrete defensins - also has the fastest waves micelles/fats are absorbed midjejunum largest number of goblet cells in ileum, also plica circulares - B12 and biles salts reabsorbed here - Peyers patches and sampling M cells - in LP and submucosa crypts of Lieberkuhn are in the small and large bowel, stem cells myenteric plexus is in between two layers of muscle, submucosal plexus aka Meissner .......................................................................................................... congenital pylori stenosis - metabolic alk, associated with exposure to macrolides duodenal atresia - double bubble sign - jejunal/intestinal atresia - disruption of mesenteric vessels --> ischemic necrosis --> segmental resorption of bowel omphalomesenteric cyst - cystic dilation of vitelline duct malrotation (of midgut) - Ladd bands, volvulus volvulus - occurs in sigmoid colon in elderly, cecum in young DIGESTION and ABSORPTION - bacterial overgrowth --> increased deconjugation of bile acids --> they become less ionized, more lipid soluble, absorbed back before micelle formation can occur - Celiacs (HLA-DQ2,8) - *duodenum*, blunted villi and deepened crypts, IgA (anti-endomysium, etc.) - refractory disease - is a sign of small bowel carcinoma or T-cell lymphoma - pancreatic insufficiency - decreased duodenal pH and fecal elastase - tropical sprue - arises after infectious diarrhea, affects DJ(I) - Whipple disease - foamy macrophages (that are filled with T. whipplei) accumulate in LP --> compression of lacteals - cardiac valves, arthralgias, CNS involvement - common in older men BOWEL and blood - necrotizing enterocolitis - formula fed premies, gas in abdomen, portal vein - small bowel obstruction - most commonly due to adhesion - ileus - hypomotility without obstruction (surgery or indirect inguinal hernia, opiates, hypoK, sepsis, meconium plug) carcinoid tumor - positive for chromogranin

Answer 24

acinar cells secrete enzymes, centroacinar cells and ductal cells secrete ions (HCO3 concentration increases at higher flow rates, high Cl at low flow rates) - intestinal phase - acinar cells are stimulated by CCK (which itself is secreted by I cells of intestine, in response to products of digestion, potentiated by Ach) - ductal cells are stimulated by secretin (and potentiated by CCK and Ach) derived from foregut - ventral bud --> uncinate and main duct - dorsal bud --> rest - both - head - annular pancreas - encircles second part of duodenum pancreatic adenocarcinoma - smoking and chronic pancreatitis, Jewish and AA males - head - body/tail --> can result in DM2 (think old person that presents with DM) - arises from pancreatic ducts - disorganized glands, cellular infiltration - Trousseau syndrome

Answer 25

Hirschsprung disease - failure of ganglion cells to descend into rectum and distal colon (RET gene), megacolon proximal to obstruction, rectal suction biopsy - presents with bilious emesis, failure to pass meconium in the first 48 hrs hereditary hemorrhagic telangiectasia - nasopharynx, GI tract angiodysplasia - right colon bleed (v.s. diverticula)

Answer 26

cells in space of Disse - store vitamin A, produce ECM bile flow is opp of blood flow zone 1 = portal triad - affected first by viral hep, ingested toxins zone 2 = yellow fever zone 3 - central vein - ischemia, CYP, *metabolic toxins*, alcoholic hepatitis

GI Flashcards

(50 cards)