GI 1.4 Final

constipation medication? MOA? AE?

• psyllium → bulk form laxative

• bisacodyl → improve peristalsis (enteric nerve); abd. cramp, electrolyte disturbance

• lubiprostone → T2 Cl channel activate; nausea, diarrhea, abd. pain

• tegaserod + prucalopride → 5-HT4 serotonin agonist; headache, abd. pain, nausea, diarrhea CV risk

opioid induced constipation medication? diarrhea medication?

• methylnaltrexone → Mu opioid ant.; renal/hepatic impair

• loperamide + diphenoxylate (CNS AE) → Mu opioid agonist

• alosetron → 5-HT3 serotonin ant.; constipation, ischemic colitis

CTX induced vomit (CINV) medication? acute + delayed CTX or migraine INV medication? MOA? AE?

• odansetron + dolasetron → 5-HT3 serotonin ant.; QT elongation, constipation, headache

• prochlorperazine + metoclopramide → dopamine ant.; extrapyramidal rxn

  • CI = PD

• aprepitant → NK-1, substance P ant.; fatigue, dizzye, anaphylaxis

vestibular nausea medication? refractory emesis medication?

• scopolamine → antimuscarinic (ACh recs.); dry mouth, mydriasis

• meclizine + diphenhydramine → anti histamine + anti muscarinic; sedation

• dronabinol → cannabinoid R agonist; sedation + dizzy

CD + UC medications? MOA? AE?

• tofacitinib → JAK-STAT inhibitor; thrombosis, PE

• mesalamine + sulfasalazine → COX inhibitor; GI upset, headache, hypersensitivity, pancreatitis

  • take folic acid

• infliximab + adalimumab → anti-TNF-a; infection, joint pain, fever, malaise, serum sickness, infusion rxn

pancreatic function? enzymes? activation?

• acinar cells= digestive enzymes, ductal cells= HCO3

• amylase, lipase, protease (trypsinogen, chymotrypsinogen)

• act.= trypsinogen → trypsin (via enterokinase in duodenum) → act. other digestive enzymes

  • excess trypsin = inc. lipase (fat necrosis, saponification), inc. elastase (BV degradation= hemorrhage→ shock)

congenital pancreatic conditions? diagnostic?

• pancreatic divisum= duct fusion fails → minor papilla drainage → recurrent pancreatitis

• annular pancreas= ventral bud migration failure → pancreatic ring around duodenum → obstruction (pain, nausea, vomit)

• accessory pancreatic tissue (ectopic)= tissue lacks pancreatic connection + indep. blood supply

• MRCP (noninvasive, visualize pancreatic ducts)

acute pancreatitis mechanism? cause? features? labs?

• premature act. of trypsinogen → autodigestion

• I GET SMASHED (idiopathic, gallstone, EtOH, trauma, steroids, mumps, autoimmune, scorpion, hyperCa/hyperTG, ERCP, drugs

• epigastric pain radiating to back, nausea, vomit, fever, cullen sign (periumbilical bruising), grey-turner sign (flank bruising)

• inc. serum amylase, trypsin, lipase (specific)

  • = inflammation, edema, acinar cell injury (acute interstitial edematous pancreatitis/AIEP)

acute pancreatitis complications?

• fat necrosis (saponification via lipase) → fever, swollen belly, nausea/vomit

  • walled off necrosis → >4 wks after; fluid + necrotic material, w/ gas = infected (Tx w/ antibiotics)

• pseudocyst → >4 wks after AIEP; encapsulated fluid w/ defined all + no solid necrotic material

• hemorrhagic (elastase) → BV damage = cullen sign + grey turner sign

• shock, abscess, splenic + portal vein thrombosis, AKI, ARDS, DIC

acute pancreatitis severity? complications?

• ranson criteria (admission) → 55+, inc. AST (250+), glucose (200+), LDH (350+), WBC (16,000+)

  • 1st 48 hrs → hematocrit drops (>10%), inc. BUN (>5), hypoCa (saponification, <8), fluid sequestration (>6L), low PaO2 (<60)

• revised atlanta classification for severe acute pancreatitis = persistent organ failure lasting 48 hrs

chronic pancreatitis cause? features? diagnosis? treatment?

• repeated inflammation (usually alcohol) → fibrosis/calcification leads to ductal + gastric outlet obstruction, splenic vein thrombosis (gastric varices)

• chronic epigastric pain (relieved by leaning forward), exocrine insufficiency or T3 DM→ weight loss, steatorrhea, DM (late), malabsorption (enzyme deficiency)

  • lead to pancreatic cancer, met. bone disease

• pancreatic calcification on CT + dec. fecal elastase

• Tx w/ pancreatic enzyme replacement → improves digestion + weight

autoimmune pancreatitis cause? types? treatment?

• immune system attack pancreas → diffuse enlargement (mimic pancreatic cancer)

• Type1 (IgG4 sec. plasma cells in pancreas → affects bile ducts, salivary glands, kidneys, LN, pancreas) OR Type2 (restricted to pancreas, associated w/ UC)

• Tx w/ corticosteroids

non-neoplastic pancreatic cyst types?

• congenital → thin-wall, via anomalous pancreatic duct dev.

• pseudocysts → @ tail; high amylase; formed via fibrosis (=obstruction) + granulation tissue wall @ intra/peripancreatic hemorrhagic

• serous cystadenoma → benign, @ tail; central stellate scar, honeycomb-like; glycogen rich

neoplastic pancreatic cyst types?

• mucinous cystic neoplasm → @ tail; ovarian-like stroma; inc. CEA

• intraductal papillary mucinous neoplasm → pre-cancerous; @ head + comm. w/ duct = jaundice

• solid pseudopapillary neoplasm → pre-cancerous

pancreatic carcinoma mutations? risk factors?

• KRAS (common), CDK2A, SMAD4 (carcinoma), TP53 (impaired DNA damage reponse), CFTR (AR impair Cl + HCO3 transport = thick obstructing sec. → EPI), PRSS1 (AD inc. trypsin act.), BRCA, lynch syndrome, peutz jegher (STK11), ATM

• smoking, chronic pancreatitis, diabetes, obesity

pancreatic carcinoma symptoms? diagnosis? treatment?

• painless jaundice, weight loss, trousseau sign (migratory thrombophlebitis= cord-like lesiosn), courvoisier sign (palpable gallbladder + jaundice); @ head = bile duct obstruction; poor prognosis

• Dx w/ CA 19-9, CT, endoscopic US

• Tx w/ whipple (pancreaticoduodenectomy) + CTX (gemcitabine)

enterobius vermicularis (pinworm) class? transmission? diagnosis?

• nematode (roundworm); cylindrical, unsegmented

• fecal-oral + autoinfection

• scotch tape test (eggs flattened on one side), perianal pruritis at night, irritability, insomnia

• Tx w/ mebendazole, albendazole, ivermectin, DEC, pyrantel pamoate

trichuris trichura (whipworm) class? transmission? diagnosis?

• nematode (roundworm); cylindrical, unsegmented

• fecal-oral via contaminated food/water

• 3Bs → barrel-shaped eggs w/ bipolar plugs, bloody diarrhea, rectal prolapse, anemia

• Tx w/ mebendazole, albendazole, ivermectin, DEC, pyrantel pamoate

ascariasis lumbricoides (roundworm) class? transmission? diagnosis?

• nematode (roundworm); cylindrical, unsegmented

• fecal-oral (ingest eggs) w/ lung migration → loeffler syndrome (cough, eosinophilia, pulm. infiltrate)

• lumpy, mammillated, thick bordered eggs in stool, larvae sputum, GI obstruction, biliary/pancreatic duct invasion, malnutrition

• Tx w/ mebendazole, albendazole, ivermectin, DEC, pyrantel pamoate

ancylostoma duodenale + necator americanus (hookworm) class? transmission? diagnosis?

• nematode (roundworm); cylindrical, unsegmented

• rhabditiform → filariform → skin penetration → lung migration → cough up + swallow → SI

• ground itch (maculopapular rash), IDA, blood in stool, protein malnutrition, growth delay

  • AD= 4 sharp teeth structure; NA= dorsal + ventral cutting plates

• Tx w/ mebendazole, albendazole, ivermectin, DEC, pyrantel pamoate

strongyloides stercoralis (threadworm) class? transmission? diagnosis?

• nematode (roundworm); cylindrical, unsegmented (tapered w/ tough cuticle)

• rhabditiform in feces → infective filariform → skin penetration → SI

  • autoinfection= lifelong, hyper infection in immunosuppressed

• eosinophilia, GI symptoms, pneumonitis (lungs), malabsorption

• Tx w/ mebendazole, albendazole, ivermectin, DEC, pyrantel pamoate

schistosoma mansoni + japonicum (bilharziasis) class? transmission? diagnosis?

• trematode (fluke); leaf shape, flat w/ no cuticle

• skin penetration via cercariae (larvae/embryonated egg = infective) in freshwater

  • mansoni (lat.); japonicum (nubby)

• acute= katayama fever (w/ eosinophils); chronic= portal HTN, LAD, HSM, esophageal varices

• Tx w/ praziquantel

taenia solium + saginata class? transmission?

• cestode (tapeworm); flat, segmented, scolex, proglottid

  • spheric, thick w/ striated shell

• ingestion of eggs (solium= pork, saginata= beef) → tissue invasion → neurocysticercosis (seizures, hydrocephalus)

  • solium = ophthalmocysticercosis

• Tx w/ albendazole, praziquantel

diphyllobothrium latum (broad fish tapeworm) class? transmission? diagnosis?

• cestode (tapeworm); flat, segmented, scolex, proglottid

• ingestion of raw/undercooked freshwater fish

• eggs w/ knobs on poles, B12 def. → megaloblastic anemia, neuro symptoms

• Tx w/ albendazole, praziquantel

hymenolepsis nana (dwarf tapeworm) class? transmission? diagnosis?

• cestode (tapeworm); flat, segmented, scolex, proglottid

• fecal-oral; common in children; direct life cycle (no int. host)

• eggs w/ polar filaments + hooks; heavy infection → GI symptoms

• Tx w/ albendazole, praziquantel

echinococcus granulosus class? transmission? diagnosis?

• cestode (tapeworm); flat, segmented, scolex, proglottid

• ingestion of eggs from dog feces

• hydatid cysts in liver, lungs, brain (CT, US); rupture → anaphylaxis (biopsy CI due to rupture risk)

• Tx w/ albendazole, praziquantel

albendazole MOA? uses? adverse effects?

• microtubule synth inhibition

• ascariasis, taenia solium (neurocysticercosis), echinococcus (hydatid disease)

• blood count + liver fxn test monitored for long term use

diethylcarbamazine citrate (DEC) MOA? uses? adverse effects?

• immobilize microfilaria

• wuchereria bancrofti, brugia malayi, loa loa, tropical eosinophilia

• headache, malaise, anorexia, weakness, mazzotti rxn

ivermectin MOA? uses? adverse effects?

• inc. Cl perm. + GABA → paralysis

• onchocerciasis, stronglyoidiasis, B malayi, W bancrofti, scabies, lice, cutaneous larva migrans (necater), oncocerca

• due to killing of worms → fever, headache, dizziness, somnolence, rash, pruritis, joint + muscle pain, hypotension

praziquantel MOA? uses? adverse effects?

• inc. Ca perm. → paralysis

• schistosomiasis, clonorchiasis, paragonimiasis, taeniasis, neurocysticercosis, hydatid disease

• fever, rash, arthralgia, neurologic, abnormalities

metronidazole + tinidazole MOA? uses? adverse effects?

• reactive free radicals → inhibits pyruvate ferredoxin oxidoreductase → kills parasite

• intestinal wall + hepatic abscess, extraintestinal amebiasis, trichomoniasis, giardiasis, H. pylori, B. fragilis, B. coli, C. diff., D. medinensis, G. vaginalis

• metallic taste, disulfiram like rxn, headache, paresthesia + dark discoloration of urine

  • C/I= neuro disorders

permethrin MOA? uses? adverse effects?

• blocks Na currents in parasites neurons

• pediculosis (lice) + scabies

• n/a

portal vein composition? HVPG? drainage?

• splenic vein + SMV

• HVPG = hepatic venous wedge pressure - free hepatic venous pressure

• drains nutrient rich blood from GIT → liver → hepatic veins → IVC

portal hypertension description? symptoms?

• pathological inc. in BP w/in portal venous system (5-10mmHg)

  • splanchnic VD = via inc. NO + PG → vasodilation → inc. portal inflow → worsen PHT → cycle of congestion + ischemia

• ascites, varices, splenomegaly, renal/pulm. dysfxn

portal hypertension treatment?

• non surgical Tx → B-blocker, underlying cause (antiviral, sobriety, immunosuppression), endoscopic variceal ligation/sclerosis

• transjugular intrahepatic portosystemic shunt (TIPS) → for refractory ascites, variceal bleed, HRS, HPS, budd-chiari

  • relative CI= hepatoma, encephalopathy, coagulopathy, thrombocytopenia

  • absolute CI= CHG, tricuspid regurg., infection, severe PH

levels of portal hypertension? cause?

• prehepatic → portal vein thrombosis, tumor

• presinusoidal intrahepatic → schistosomiasis, congenital fibrosis

• sinusoidal intrahepatic → cirrhosis, NASH, amyloidosis, acute hepatic infection

• posthepatic → budd chiari (hepatic vein thrombosis), RHF, constrictive pericarditis

collateral hepatic pathways?

• esophagus= L gastric vein → esophageal plexus

• rectum= sup. rectal vein → middle/inf. rectal vein

• umbilicus= paraumbilical veins → abdominal wall veins (caput medusae)

• retroperitoneum= sappey’s veins

• splenorenal= splenic vein → L renal vein

varices location? treatment?

• esophageal (most common, life threatening bleed), gastric (mosaic/snake skin mucosa), rectal (mimic hemorrhoids), ectopic (duodenum)

• acute= blood transfusion + vol. replacement as needed, band ligation, sclerosing agent injection, emergency TIPS

  • long term= a+B blocker (carvedilol), nonselective B blocker (propranolol), TIPS

hepatic encephalopathy features? treatment?

• neurotoxins, excess NH3 (into astrocyte → = glutamate→ astrocyte swelling)

  • worsened via ammonia genesis → diuretics cause hypokalemia, high protein intake, TIPS, mannitol

• lactulose (acute Tx; acidifies colon + excess H+ traps NH3) + rifaximin (for prophylaxis; dec. NH3 prod. bacteria, stays in intestine)

hepatorenal syndrome cause? findings?

• splanchnic VD ( via inc. NO + PG)→ dec. output/BP → dec. renal perfusion + VC of aff. arterioles (RAAS act.) → ascites + functional AKI

  • ascites= hypoalbuminemia (dec. oncotic pressure + inc. hydrostatic pressure), RAAS act. (aldosterone retain H2O+Na- dilutes albumin), splanchnic VD (SMA, IMA)

• inc. creatinine + BUN, oliguria, hyperkalemia, dec. GFR

hepatopulmonary syndrome cause? features? diagnosis?

• intrapulmonary shunting → V/Q mismatch → liver disease, pulmonary vascular dilation, hypoxemia

• platypnea (SOB when sitting up, better laying down), orthodeoxia, cyanosis, clubbing, cut. telangiectasia (spider angioma)

• bubble study → delayed bubble in left heart meaning they pass thru dilated pulm. capillaries

hepatic hydrothorax? hypersplenism? cirrhotic cardiomyopathy? hepatic osteodystrophy?

• pleural effusion in cirrhosis w/o cardio/pulm disease = dyspnea, cough hypoxemia

• inc. splenic venous pressure → congestion → hypersplenism/splenomegaly = anemia, leukopenia, thrombocytopenia (via sequester)

• hyperdynamic circ., plasma expansion, autonomic dysfxn= impaired contractility + diastolic dysfxn

• uncoupled osteoblast/clast activity; involve TNF-a, IGF-1, vitK= osteomalacia + osteoporosis in cirrhosis