GI Pathophys

this part of esophagus prevents aspiration into trachea and is made of SKELETAL muscle

this part of the esophagus prevents reflux of gastric contents into esophagus and is and of SMOOTH msucle

upper esophageal sphincter

lower esophageal sphincter

most bacteria in small/large intestine are

aerobes

anaerobes

anaerobes (enterococci)

Upper _____ of esophagus is skeletal muscle

lower ______ of esophagus is smooth muscle

1/4, 3/4

1/2, 1/2

1/3, 2/3

2/3, 1/3

1/5, 4/5

upper 1/3 skeletal

lower 2/3 smooth

KNOW

the upper esophageal sphincter constricts at

C4-C6

C5-C6

C6-C7

C7-T1

C6-C7 (cervical constriction)

KNOW

the aortic arch and left bronchus (middle esophageal constriction) occurs at

T1-T2

T2-T3

T3-T4

T4-T5

T3-T4

KNOW

lower esophageal sphincter constricts at the level of

T9-T10

T10-T11

T11-T12

T10-T11

7+4 = 11, these are for the second vertebrae

so UES constricts at C6-C7

middle ES constricts at T3-T4

so LES constricts at T10-T11

KNOW

what kind of ephithelium lines the mucosa of the esophagus?

non-keratinized stratified squamous epithelium

keratinized stratified squamous epithelium

simple squamous epithelium

simple columnar epithelium

non-keratinized stratified squamous epithelium

non-keratinized bc were not dealing w skin/hair

stratified squam means many layers of squamous cells, so this allows for protection (makes sense bc esophagus needs protection against abrasive food/stomach acid)

Meissner's nerve plexus is in the _______ layer of the esophagus

mucosa

submucosa

muscularis externa

serosa/adventitia

submucosa

I think meis-sner sounds like "my"sner nerve plexus

and its in the SUBmucosa so I think, at lunch im going to eat my sub

so MYsner , SUBmucosa

Its purpose is to control glandular secretions, modulate water and electrolyte transport, influence local blood flow, and provide secretomotor innervation to the submucosal glands

the muscularis externa layer of all GIT muscles are composed of only smooth muscle, except

stomach

esophagus

spleen

small intestine

esophagus

Aurbach's nerve plexus controls the motility of the GI tract and is located in which layer

mucosa

submucosa

muscularis externa

serosa/adventitia

muscularis externa

if u remember it controls motility then u know its the layer with muscle in it

or u can think of how Auerbach's plexus is also called MYENTERIC plexus, and myenteric means muscle, so its in the muscularis externa

swallowing reflex is initiated in the

pons

esophagus

glottis

medulla oblongata

medulla oblongata

mucosa in the stomach is lined with what epithelium?

simple columnar

pepsinogen is secreted by which gastric glands?

mucous neck cells

chief cells

parietal cells

endocrine cells

chief

think of a football player on the chiefs drinking pepsi idk

note- it is the inactive form, pepsinOGEN, not pepsin, thats secreted bc bc we want to prevent the self-digestion of the stomach lining and the cells producing the enzyme

anything ending in OGEN is a precursor

gastric acid (Hcl) and intrinsic factor (IF) are secreted by ______

mucous neck cells

chief cells

parietal cells

endocrine cells

think, what IF the pariet-L cells secrete hcL?

so IF for intrinsic factor, and pariet-L , HC-L

gastrin, histamine, seroronin, and grehlin are secreted by which gastric glands

mucous neck cells

chief cells

parietal cells

endocrine cells

endocrine cells

the endocrINe cells secrete hormones ending in IN (gastrIN, serotonIN, ghrelIN, histamINe, etc)

this hunger hormone stimulates appetite

gastrin

ghrelin

ghrelin

think ghrr my stomach im hungry

the ATPase proton pump actively secretes _____ into the lumen

carbnonic anhydrase

H+

Cl-

Hcl

H+

gastrin _____ gastric juice secretion

increases

decreases

increases

vagal stimulation and histamine ______ gastric juice secretion

increase

decrease

increase

vagal is parasympathetic, so rest and DIGEST

and histamines think high stress, stomach churning

hence why ANTIhistamines like dramamine calm ur stomach

the hormone secretin ____ gastric juice secretion

Increases

decreaes

DECREASES

why?

Secretin decreases gastric acid secretion to neutralize acidic stomach contents in the duodenum, protecting the intestinal lining.

prostaglandins ______ gastric juice secretions

increase

decrease

decrease

T/F: gastrin and motilin ENHANCE gastric emptying

T

the small intestine is lined with_______

keratinized stratified squamous epithelium

simple squamous epithelium

simple columnar epithelium with goblet cells

simple columnar epithelium

why?

simple so one layer, so allows for easy absorption! which is what we want in the small intestine

but why do we want goblet cells? to secrete mucous to help digest

what part of the small intestine are peyer's patches most prominent, and why does this make sense?

duodenum

jejunum

ilieum

ileum

Peyer's patches are concentrated in the ileum, the most distal segment of the small intestine, to maximize exposure to gut-resident pathogens, which are more abundant and diverse there. The distal location allows the immune system to develop a broad-spectrum immune response to a vast array of antigens before they can spread systemically, effectively guarding against ingested threats.

peyer's patcches are mostly in what layer of the small intestine

mucosa

submucosa

muscularis externa

serosa

mucosa

crypts of lieberkun are located in what organ and what do they secrete

small intestine (and large intestine?)

secrete HCO3-, mucus, and lysozymes

what is the immune function of the appendix

contains lymphoid tissue (MALT)

what 2 vitamins does the microbiome in the large intestine produce

B and C

A and K

K and B

D and K

K and B

kNOW

the proximal part of the anorectal canal is (above/below) the pectinate line, and drains to the (portal system/systemic circulation)

Proximal is ABOVE, and drains to the Portal system

KNOW

the distal part of the anorectal canal is (above/below) the pectinate line, and drains to the (portal system/systemic circulation)

distal is BELOW the pecinate line and drains to the systemic circulation

which part of the anorectal canal is sensitive to pain/touch/temperature

proximal

distal

distal

anal glands are in the _________of the anorectal canal

mucosa

submucosa

submucosa

the ampulla of vater is where what 2 ducts meet

pancreatic and common bile ducts

cystic and common bile ducts

cystic and pancreatic ducts

pancreatic and common bile

islants of langerhan are in what organ

pancreas

what cells in the liver make bile?

hepatocytes

kupffer cells

stellate cells

pit cells

hepatocytes

macrophages of the liver; activation of these cells lead to cirrhosis

kupffer cells

stellate cells

pit cells

kupffer cells

think KUPF is TOUGH; if u have an infection, these macrophages will try and fight it off

which cells produce collagen and store vitamin A in the liver

kupffer cells

stellate cells

pit cells

stellate cells

stellAte cells store vitamin A and produce collAgen to help heAling

these cells in the liver kill tumor cells and virus infected cells

pit cells

hepatocytes

kupffer cells

pit cells

secretin comes from

stomach

duodenum

jejunum

nervous system

duodenum

secreDin comes from Duodenum

what is cholecystokinin (CCK) and what does it do

a hormone that increases stomach acid secretion (to help digestion) and DELAYS gastric emptying to allow for better nutrient absorption from small intestine

_____= difficulty swallowing

_______= painful swallowing

dysphagia

odynophagia (think oh damnophagia, as in oh damn thats painful)

KNOW

most common cause of esohpageal stricture (abnormal narrowing of esphagus)

gerd

esophagitis

schatzki ring

tumor

gerd

idiopathic esophageal stenosis due to fibrous ring

schatski ring

_____ = a weak area in the posterior wall of pharynx above upper esophagheal sphincter

killian's triangle

schatzki ring

mallory-weiss ring

bochdakel hernia

killian's triangle is weak; think achilles heel is weak, and achilles kind of rhymes with killian's

abnormal esophageal motility and peristalsis due to increased lower esophogeal sphincter tone

esophgeal achalasia

esophagitis

gerd

barett esophagus

esophogeal achalasia

degeneration/loss of inhibitory neurons in myenteric plexus of esophageal wall is _________ esophageal achalasia

primary (idiopathic)

secondary

primary

which 5 pills most commonly cause pill esophagitis

bisphosphanates

nsaids

tetracyclines

iron

vitC

______ is a risk factor for gerd

upper esophageal dysfunction

lower esophogeal dysfunction

lower

metaplasia of distal esophagus mucosa and conversion from squamous to columnar epithelium

barett esophagus

mallory weis syndrome

adenocarcinoma

esophageal perofration

barett esophagus

think BE is from S to C

so Baretts Esophagus is when Squam is converted to Columnar

KNOW

barett's esophagus has a high risk of turning into what kind of cancer

squamous cell

adenocarcinoma

adenocarcinoma

cleaning agents (alkaline) would cause what kind of necrosis to the esophagus?

liquefactive

coagulative

a mixture of both

aLkaline causes Liquefactive necrosis

aCidic causes Coagulative necrosis

longitudinal mucosal/submucosal LACERATIONS at lower esophagus/junction, usually heal spontaneously within 1-2 days; NO perforation

mallory weiss sydnrome

boerhaave syndrome

esophageal varices

hiatal hernia

peptic ulcer

mallory weiss syndrome

blunt trauma esohageal perforation usually occurs in _____ of esophagus

upper 1/3

upper 1/2

upper 2/3

upper 2/3

full thickness esophageal tear, can lead to mediastinitis

mallory weiss syndrome

boerhaave syndrome

boerhaave syndrome

think of malllory as a young small girll, much weaker than a big boar pig (boerhaave syndrome), so mallory weiss- only supefiaical tear, heals spontaneously

whereas boerhave- seriuos complications

dilated tortuous submucuosal veins in distal esophagus, from portal hypertension

mallory weiss syndrome

boerhaave syndrome

barett's esophagus

esophagitis

esophageal varices

esophageal varices

zenker's diverticulum is located where, and is a risk factor for what kind of esophageal cancer

adenocarcinnoma

squamous cell

zenker's diverticulum (diverticulum= outpouching) is located in the poZterior of the upper esophagus due to killlian's triangle, and increases risk for Zquamous cell carcinoma

delayed gastric emptying WITHOUT mechanical obstruction, often caused by diabetic neuropathy

gastroparesis

erythromycin and azithrymocyin before 2 weeks of age is a risk factor for what condition

infantile hypertrophic pyloric stenosis

cancer risk for this type of ulcer is HIGH

gastric ulcer

duodenal ulcer

gastric

black stool (melena) is indicative of

upper gi bleed

lower gi bleed

upper

traverler's diarrhea is most commonly caused by what bacteria

enterohemorrhagic e coli

enteroinvasive e coli

enterotxoci e coli

shigella

Enterotoxigenic E coli (ETEC), so ETEC has a T and is the most common cause of Traveler's diarrhea

bile secretion by the gallbladder is initiated via ________ innervation

sympathetic

parasympathetic

parasympathetic

why? bc parasympathetic is rest and digest

_______ can go to feces, urine, or enter hepatic circulation

unconjugated biliribun

conjugated bilirubin

biliverdin

urobilinogen

uribilinogen

ogen means precursor, so it is a precursor that goes one of 3 ways (to the feces, urine, or hepatic circulation)

motilin is produced in the _______; what is its purpose?

stomach

small intestine

large intestine

pancreas

small intestine

purpose is to increase stomach and small intestine mobility

note- secretin has the OPPOSITE function

this outpouching of the esophageal wall includes the mucosa and submucosa

intramural diverticula

false diverticula

true divertila

false diverticula

if it affects ALL THE LAYERS, thats a true diverticula, but submucosa and mucosa are just 2/4 of the layers i think

this outpouching of the esophageal wall includes only the mucosa

intramural diverticula

false diverticula

true divertila

intramural

think intraMural, intraMucosa, just includes the mucosa

posterior diverticulum of upper esophagus due to outpouching at Killian's triangle at pharynx

zenker's diverticulum

zenKer's divirticulum involves Killian's triangle, and think achillies heel is weak, so achilles' (killian's) triangle is weak, which is why this area of the esophagus is susceptible to outpuouching

this condition occurs when there is increased lower esophageal tone (muscle contraction) due to degeneration/loss of inhibitory neurons in myenteric plexus; leads to esophageal dilation

esophageal achalasia

esophagitis

esophageal diverticula

esophagael stricture

esphageal achalasia

schatzki ring is a type of

esophageal achalasia

esophagitis

esophageal diverticula

esophagael stricture

esophageal stricture, bc its a stenosis of the espophagus

IMPORTANT

what two receptors are in the vestibular apparatus within the inner ear?

why is this important

M1 (muscarinic receptor) and H1 (histamine receptor)

D2 (dopamine receptor) and 5-HT3 (serotonin receptor)

M1 (muscarinic receptor) and D2 (dopamine receptor)

5-HT3 (serotonin receptor) and NK1 receptor (substance p receptor)

M1 and H1

so msucarinic and histamine receptor

this is important bc the vestibular appratus is for the inner ear; so if ur nauseaus due to an inner ear problem (motion sickness, meneieres, labrynthitis), ur only gonna get nausea relief if we block M1 and H1!!!!

for example, dramamine is an H1 antagonist, and thats why it works so well for motion sickness

IMPORTANT

_________ is unprotected by the blood-brain barrier (BBB) , allowing it to detect circulating toxins and drugs in the bloodstream, which is a key aspect of its function in initiating the vomiting reflex

NTS (nucleus tractus solitaris)

CTZ (chemoreceptor trigger zone)

vestibular apparatus

CTZ

think CTZ is not protected by the BBB

anticipatory chemo induced nausea/vomitting is mediated by __________

delayed chemo induced nausea/vomitting is mediated by _________

Serotonin (5-HT)

Dopamine (DA)

GABA

substance P

anticipatory- GABA makes u vomit Before chemo

delayed- dopamine and substance P

gastroparesis is a ________ cause of delayed gastric emptying

structural

functional

FUNCTIONAL

often cuased by diabetic neuropathy or meds like glp1s/opioids/anticholinergics

use of _______ before 2 weeks of age of the infant can lead to infantile hypertrophic pyloric stenosis

tetracyclines

aminoglycosides

penicillins

macrolides

fluroquinolones

if u feed a newborn a big MAC(rolide) it will get pyloric stenosis

which type of hiatal hernia is more common?

rolling- goes through diaphragmatic defect near the esophagus

sliding- goes through the espophageal hiatus

sliding

protrusion of the upper part of stomach into thoracic cavity through the diaphragm is called

hiatal hernia

most common type of congenital diaphragmatic hernia

bochdalek

morgagni

bochdalek

gastritis is most commonly caused by which infectious agent?

C dif

E coli

Staph aureaus

Cholera

H pylori

H pylori

list the agents causing peptic ulcer disease in order from first to 3rd leading cause

NSAIDs, alcohol, H. pylori

H. pylori, alcohol, NSAIDs

H. pylori, NSAIDs, alcohol

alcohol, H. pylori, NSAIDs

NSAIDs, H. pylori, alcohol

h pylori, nsaids, alcohol

think a girl named HaNnAh (HNA) had peptic ulcer disease

H pylori (leading cause)

NSAIDs

Alcohol

increase in gastric acid due to gastrinoma (a gastrin secreting tumor), mostly in the pancreas and duodenum

mallory weis syndrome

barett's syndrome

zollinger-ellison syndrome

meckel syndrome

zollinger-ellison syndrome

melena indicates

upper gi bleed

lower gi bleed

upper gi bleed, so bleeding proximal to the ligament of treitz

autoimmune chronic metaplastic atrophic gastritis is mediated by

autoreactive T cells against parietal cells

auto-abs against parietal cells and IF

both

neither

both

duodenal ulcer _____ food

is exaggerated by

relieved by

is relieved by food!! Dude (duodenum) give me food

KNOW

pain associated with a gastric ulcer is _____ after meals

pain w a duodenal ulcer is ______ after meals

immediated

delayed

gastric- immediate; so these pts might not want to eat since it hurts

duodenal- delayed; thats why ppl w a duodenal ulcer feel better after eating; DUDE give me food pls , for a DUDEonal ulcer; these people might eat more often since their pain goes away after meals

bright red blood in poop

hematochezia

melena

hematemesis

meletochezia

hematochezia

T/F: antrum is a frequent location in stomach for gastric cancer

T

what type of primary constipation is associated with abnormal perception of bowel activity

normal transmit time constipation

slow transit constipation

pelvic floor dsfunction

normal transit constipation

antacids containing aliuminium and calcium cause

constipation

diarrheah

constipation

so magnesium- diarrhea

aluminium/calcium- constipation

overflow incontinence (leakage of liquid stool around impacted stool) is a type of _____ fecal incontenience

retention

nonretentian

retention (encopresis)

KNOW

these two bacteria cause inflammatory diarrhea but do NOT cause dystentery (bloody diarrheah); instead, they invade lymphatics

salmonella nontyphoid and shigella

salmonella typhoid and shigella

salmonella typhoid and yersina enterocolitica

entamoeba histolytica and shigella

Salmonella Typhoid and Yersina Enterocolitica

Sam T and Yersi sitting in a tree, KISSING, but NO DYSENTERY

pathogens release toxins,. bind to enterocyte receptors, and cause increase in efflux of ions and water into bowel lumen, leading to watery diarrheah

inflammatory (invasive) diarrhea

noninflammatory diarreha

noninflammatory diarrhea bc NO CYTOTOXIN

this type of diarreah causes intestinal mucosal invasion and cytotoxin production; it inflames/destroys mucosa/causes dysentery

inflammatory (invasive) diarrhea

noninflammatory diarreha

inflammatory

Norovirus/rotavirus= most common cause for

inflammatory (invasive) diarrhea

noninflammatory diarreha

Nonflammatory diarrheah, Norovirus/rotavirus

vibrio cholera is ______ diarrheah

inflammatory

noninflammatory

noninflammatory

which of these E. colis is NON inflammatory

enteroinvasive e coli (EIEC)

enterohemorrhagic e coli (EHEC)

enterotoxigenic e coli (ETEC)

enterotoxigenic e coli (ETEC)

seems like if it has the word toxic in it it WOULD be inflammatory but its NOT

note- ETEC is the most common cause of Traveler's diarrhea

C dif is inflammatory or noninflammatory diarrheah?

noninflammatory

lactose intolerance, celiac, chronic pancreatitis, bile acid deficiency, and ischemic colitis can cause _______ noninfectious diarrheah

high osmotic gap

normal osmotic gap

low osmotic gap

high osmotic gap

KNOW

the most common cause of diarreah in individuals coming back from resource limited countries

norovirus

staph aureaus

enteroinvasive e coli (EIEC)

vibrio cholera

exterotoxigenic e coli (ETEC)

ETEC

this is the only E coli with a T in it, so think T for traveler's diarrhea

increased permeability of intestinal epithelial lining due to damage of tight junctions

barett's esophagus

leaky gut syndrome

intestinal obstruction

diverticulum

esophogeal hernia

leaky gut syndrome

most common cause of small bowel obstruction in adults

adhesions

atresia

intuseption (telescoping bowel)

volvulus (torsion)

adhesions