CH10

hollow tube
peritoneum
blood supply
lymphatic system
automatic nervous sys innervation
GI divided into upper and lower portion

Serosa
muscularis
submucosa
mucosa

adventitia

peritoneum (serosal surface)

mesentery arteries
portal system drains venous bld from small and large intestine

mastication
digestion
deglutition
digestion
salivary glands
absorption
excretion
processing

by digestive juices

voluntary swallowing;
food enters esophagus
peristalsis

smooth muscle contraction

in the mouth with saliva,
in stomach with HCl and gastric enzyme
duodenum: mixed with bile, pancreatic juice, intestine enz, lysis of proteins, CHO, lipids

chemically digested food taken into cells of mucosa (mostly in small intestine)

processing is under control of neural and neuroendocrine reflexes and enzyme release

amylase

digestion of starch

pepsin
HCl
gastrin
intrinsic factor

digestion of proteins
stim secretion of HCl
mediates absorption of B12

enterokinase
cholecystokinin
secretin

activate pancreatic enz
stim gall bladder contraction and pancreatic secretion of bicarbs
stim secretion of pancreatic trypsin and chymotrypsin

dilation above spasm in esophagus
cant swallow

abnormal or strained swallowing

achalasia
megacolon
dysphasia
achlorhydria
malabsorption
occult hemorrhage
hematemesis, hematochezia

decreased HCl

dental caries
infectious diseases
circulatory disorders
multifactorial disorders
obstructive disorders
functional disorders
neoplasms

gum disease

gastroenteritis
C. difficile

hemorrhagic lesions

peptic ulcer
inflammatory bowel disease

indigestion
malabsorption

squamous cell carcinoma (SCC)

chewing tobacco, smoking, alcoholism, HPV

lips, tongue, mouth

begins as dysplasia, becomes carcinoma in situ, then invasive carcinoma

leukoplakia
erythroplakia
ulcer
crater
nodule

parotid
submandibular
sublingual

infectious or autoimmune (Sjögren's disease)

as swelling of glands or xerostomia, xeropthalmia

major or minor salivary glands (60% benign)

pleomorphic adenoma

dysphagia
esophageal pain
aspiration / regurgitation
atresia
hiatal hernia
achalasia
esophagitis
varices
carcinoma

difficulty swallowing

colic or retrosternal pain (heartburn)
odynophagia

pain during swallowing

food from oral cavity and lead to aspiration pneumonia

lack of lumen
with or without esophageal tracheal fistula

displacement of cardiac portion of stomach

circulatory disturbance

developmental anomaly where the connection between esophagus and trachea is broken;
food cannot pass into stomach

gastroesophageal reflux

displacement of cardiac portion of stomach

relaxation or weakening of the stomach;
acid flows back into esophagus

smoking, caffeine, coughing

dilates (opens) when swallowing food and contracts when food is swallowed

when unable to relax LES, leading to spasm of LES (dilation of esophagus prox to site of spasm)

dysphagia (inability to swallow)

LES insufficiency

esophageal varices (dilated veins)

esophageal varices

hematemesis (bleeding)

reflux of gastric juice

virus
fungi
bacteria superinfection

chemical irritants (exogenous chemicals or drugs)

reflux of ulcerations can occur

pepsin and HCl

GERD

peptic esophagitis, inflammation, and ulceration by squamous epithelia

metaplastic columnar epithelia
if not repaired, can give rise to peptic ulcers

Asia, China, Africa
men > women

alcohol, tobacco abuse

begins in lower esophagus

2 years

pain in swallowing
bleeding
invasive spread to lymph nodes
poor prognosis

gastritis, peptic ulcers, and carcinomas

developmental , projectile vomiting due to hypertrophy in smooth muscle of pylorus

unable to empty stomach leading to projectile vomiting needing surgical intervention

obstruction of the exit portion of the stomach or irritation and disturbed motor fxn of the gastric musculature → vomiting

related to ulceration of mucosa,
caustic action of HCl,
enzymatic action of pepsin in gastric juice

gastric ulceration leads to hematemesis or melena

nausea, loss of appetite, aversion of food

chronic bleeding ulcers may cause iron deficiency anemia

lack of intrinsic factor
missing gastric protein that absorbs B12
results in pernicious anemia

short

shallow mucosal defects

deeper, superficial bleeding

profound bleeding related to severe burns of external body

ulcers can heal if circ disturbances are removed or corrected

chemicals, drugs, alcohol, NSAIDs, aspirin

elderly, h. pylori, autoimmune

b12, pernicious anemia, intrinsic factor

labels as dyspepsia (nonspecific)

pain (hcl pepsin)
vomiting (obstruction)
bleeding (ulceration)
dyspepsia (anormal stomach fxn)

bleeding (microcytic anemia (IDA))
pernicious anemia (lack of intrinsic factor)

erosive and hemorrhagic
neutrophils = predom inflammatory cell in superficial epith

no symptoms but may cause dyspepsia, anorexia, nausea and vomiting, hematemesis, melena

acid suppression (H2 receptor antagonist)
antiemetics (metoclopramide)

erosions, ulcers

sudden inflammation or swelling in the lining of the stomach

diffusely hyperemic gastric mucosa

surface of epith / glands intact with scattered neutrophils among epith cells or within mucosal glands
lamina propria

moderate edema and vascular congestion

older age

Far east, Eastern Europe

decreased secretion of pepsin,
dyspepsia

multifactorial but can be due to:
gastric juice
mucosal barrier defects
H. pylori
genetics
exposure to pepsin and HCl

HCl, pepsin
needed for ulcer development

H2 antagonist (cimetidine)

stress, shock, NSAIDs, smoking
reduces mucosa resistance

gastrin

stomach of older pts and proximal duodenum

punched out lesion into deep layer
HCl keeps bottom clean of necrotic tissue

bottom of ulcer replacing the mucosa consists mostly of granulation tissue and cell debris / inflam cells

from eroded mucosal bld vessels

fibrosis and scarring

hemorrhage
pancreas penetration
perforation
Cicatrization

acute pancreatitis

peritonitis due to extending

excessive fibrosis, scarring can lead to stenosis

in the distal portion of the stomach and prox to duodenum

>50 yo

1-3 hrs after a meal or at night;
pt is able to point to pain

eradication of H. pylori infection

polyps, leiomyoma

hyperplastic, tubular, villous

pts with pernicious anemia

adenocarcinoma (common)
lymphoma

Japan (poss. nitrosamines in food or h. pylori)

decreased refrigeration; bacteria converts nitrates to nitrites

superficial
polypod-protrude in the stomach
ulcerated
diffusely infiltration (linitis plastica)

adenocarcinoma

in distal part of stomach
pylori and atrium

weight loss, anemia, vomit, bleeding, weakness, irritation

gastric carcinoma

mucin filling cytoplasm displaces the nucleus to the periphery and gives the cell the appearance of a signet ring

bilaterally to ovaries
Kuechenberg's tumor

MALT, Peyer's patches

stomach of older pts and proximal duodenum

developmental abnormalities
diverticulosis, obstructions, hernias
vascular disorders
IBS
infections
malabsorption
neoplasms

Hirschsprung's disease
congenital diverticular
Meckel's

marked dilation of large intestine (megacolon) notable prox to narrowing of rectum of sigmoid colon

abnormal innervation of rectum and sigmoid colon

permanent spasm
no passage of feces
intramural ganglion cells do not develop

formation of diverticular
outpouchings intestinal wall
sigmoid colon*
protrusion through muscle wall
abscess, fistula

chronic constipation
obstructed with fecal matter
infected, bleeding

low fiber diet
straining during bowel movement

formation of pericolonic abscesses, fistulas, or pericolonic fibrosis

hemorrhoids
angiodysplasia
ischemia bowel disease
chronic ischemia
acute thrombosis of mesenteric
nonocclusive intestinal infarcts

hemorrhoids=dilated veins;
risk factor: pregnancy, genetics

vascular lesion of colon;
dilated thin walled vessels
serves as anastomosis between arterial and venous circ in the mucosa and submucosa of the colon

elderly

blood flows through segments of intestine

thrombi or emboli

atherosclerosis, narrowing

transmural infarction of small intestine

thickened intestinal wall,
narrow lumen

colon and terminal ileum; can present as acute appendicitis; numerous skip lesions

granuloma, fibrosis, diarrhea, weight loss, abdominal pain, bleeding

cobblestone appearance

diffuse, entire colon

becomes like sandpaper, bleeding, pain;
lesions increase becoming flat and pitted (football or pig skin) ;
limited to mucosa!

intestinal dilation and megacolon (toxic),
left side affection
ulcerations
pseudopolyps
distortion of crypts, aggregates of leukocytes
recurrent inflammation
dysreg immune response to microbiota

regenerating foci of epith may undergo malignant transformation

antibiotic use
microbial exposure early and late in life
possibly due to diet

20s and 30s, begins in late teens;
familial predisposition, extraintestinal complications

Crohn's distribution = segmental, includes ileum whereas ulcerative colitis is diffuse colon only;
no transmural, granuloma, or fistula in UC;
no megacolon in Crohn's

azathioprine
Azasan, Imuran
mercaptopurine
Purinethol, purixan

vedolizumab, Entyvio
ustekinumab, Stelara
infliximab, Remicade
adalimumab, Humira
golimumab, Simponi

TNF inhibitors; work by neutralizing protein produced by immune system

IL-12, IL-23

food poisoning
viral infections
infectious diarrhea
small-intestine infection
large intestine infection
c. difficile

e coli, v cholera, g lamblia, rotavirus

e coli, shigella, Norwalk virus, entamoeba

pseudomembranous colitis (overgrowth of c difficile)
exotoxin in surface of mucosa
bact toxins ingested from preformed food
lytic action of bacteria and colonization
enterotoxigenic bacteria
typhoid fever

enterotoxigenic bacteria

enterotoxigenic bacteria

obstruction of lumen of appendix; hardened piece of feces

inflam of peritoneal lining of abd cavity;
can be secondary to rupture of stomach and appendicitis

spreads infection from fallopian tubes (neiss.)
rupture of abscess
infection of pre-existing ascites

acute pancreatitis
due to rupture of gallbladder
edematous
exudate of fluid into abdomen

gall stones

surgically, repairing rupture

acute peritonitis, spinal cord injury

atresia / stenosis
structures
intussusception

invagination of segment into another caused by tumor

impacted feces, foreign bodies, gallstones
malignant / inflam structures
adhesions, hernias, volvulus

scar tissue

twisting or narrowing of intestines causing bowel instruction

rotation and twisting of intestine around mesenteric attachment site

protrusion of abd contents through abd wall;
weakness or defect in wall

inability of intestines to absorb nutrients from food;
cant properly process nutrients or transport nutrients from intestine to liver;
impaired because of gastric biliary or pancreatic insuff or bact overgrowth and parasites

intraluminal digestion of food depends on proper secretion of digestive juices

decreased digestive juices
digestion impaired
decreased absorption of nutrients

intestinal disease, like Celiac Sprue or Whipple's;
systemic diseases like scleroderma and amyloidosis

problem in transport of nutrients from intestine

malabsorption

inadequate intraluminal digestion
reduced intestinal bile salt concentration
primary mucosal absorptive defects
impeded transport of nutrients

exocrine pancreatic insuff
chronic pancreatitis
cystic fibrosis

impaired micelle formation
liver disease
cholestasis
abnormal bact proliferate in small bowel
post gastrectomy states

celiac sprue
enteritis
abetalipoproteinemia
intestinal resection
endocrine and metabolic disorders

lymphatic obstruction (lymphoma)
congestive heart disease
intestinal ischemia

deficiency of gastric juices: post gastrectomy conditions, atrophic gastritis (stomach resection)
deficiency of bile: biliary obstruction, liver disease, Crohn's
deficiency of pancreatic juices: chronic pancreatitis
bacterial overgrowth: Giardia Lamblia

hypersensitivity to gluten (gliadin): early child; lab tests for ab to tissue transglutaminase

bacteria that affects visitors to tropics

bacteria infection that leads to malabsorption

passage of lipids into circulation

prevents bowel from absorbing important nutrients, fluids, including proteins, fats and vits

anemia, bleeding;
osteopenia: calciol and VD deficiency;
amenorrhea, impotence, infertility;
purpura, dermatitis;
peripheral neuropathy

iron, folate, and B12 deficiency

vit K deficiency

calcium and VD deficiency

VK deficiency and VA deficiency

folate and B12 deficiency

GI lymphoma
congestive heart failure with intestinal ischemia
scleroderma
amyloidosis
dec nutrients absorbed
steatorrhea

malabs of fats leading to deficiency of fat soluble vitamins

non-neoplastic polyps
neoplastic benign polyp
malignant neoplasms

hyperplastic polyp
inflammatory
juvenile
peutz-jeghers
lymphoid

tubular adenoma
villous
tubulovillous

adenocarcinoma
carcinoid

familial polyposis coli
Gardner's Syndrome
HNPCC
dietary factors
interaction of carcinogens
DNA not repaired right
Red meats / fried fat
APC gene ability as tumor suppressor

adenomatous polyposis develops in older or adolescent;
multiple polyps prob evolve to adenocarcinoma
APC gene: germ line mutation

develop form normal mucosal
DNA repair enzyme def
allows certain mutations to persist with no repair of damaged DNA

tumors develop form epith cells lining crypts and villi,
no apoptosis
undergo malig transform bc of oncogenes
polyps protrude into the lumen

2fold to 3fold

lumen of intestine (because most have epithelial origin)

large intestine (colorectal cancer)

colonic cancers do not evolve form polyps but from normal mucosa

intestinal
tubular adenoma is pedunculated and has stalk;
sessile and has fingerlike villi projecting from base toward lumen of intestine;
increases with age

ulcerated;
forms intraluminal fungating of ulcerating masses

narrow lumen, obstruction for passage of feces, constipation, pencil like stools, blood in feces;
produces 'napkin ring' stenotic lesions

carcinoembryonic ag

neuroendocrine cells that contain granules, polypeptide hormones

serotonin, polypeptide hormones (causing diarrhea, hypermotility)

right side heart valves