Ch 17 - GI Tract Flashcards
most common site of esophageal atresia
at or near the tracheal bifurcation
MC site of intestinal atresia
duodenum
MC form of congenital atresia
imperforate anus
failure of the cloacal diaphragm to involute
imperforate anus
incomplete closure of the abdominal musculature with herniaition of abd vicera into a membranous sac
omphalocele
MC site of ectopic gastric mucosa (inlet patch)
upper 1/3 of esophagus
small patches of etopic mucosa in the small bowel or colon leading to occult blood loss d/t peptic ulceration of adjacent mucosa
gastric heterotopia
blind outpouching of alimentary tract that commuicated with the lume and includes three layers of the bowel wall
true diverticulum
MC true diverticulum and MC location
Meckel’s, ileum
failed involution of vitelline duct
Meckel’s
rule of 2’s
- 2% of pop
- w/in 2 ft of ileocecal valve
- 2 in long
- 2x as common in males
- usually see s/s by 2 yo
MC site of aquired diverticula
sigmoid colon
- regurgitation
- projectile nonbilious vomiting
- frequent re-feeding
- presents btwn 3-6 wk of life
- firm, ovid, 1-2 cm abd mass
congenital hypertrophic pyloric stenosis
distal intestinal segment that lacks both missner submucosal and auerbach meyenteric plexus
hirschprung disease
- neck mass
- regurgitation
- halitosis
- > 50 yo
Zenker divertiulae
- increased lower eso sphincter tone
- inability to relax LES
- eso aperistalsis
- d/t ganglion cell degeneration
primary achalasia
- result of chagas disease
- destruction of the meyenteric plexus
- failure of peristalsis and eso dilation
secondary achalasia
- achalasia
- ACT hormone-resistan adrenal insufficiency
- alacrima
Allgrove (triple A) syndrome
longitudinal tears in the GE jxn ass’d with severe retching or vomiting secondary to acute ETOH ingestion
Mallory-Weiss tears
- severe chest pain
- tachypnea
- shock
- severe mediastinitiis
- transmural tearing
- rupture of disal eso
Boerhaave syndrome
MC carcinoma to arise from barrett eso
eso adenocarcioma
MC site of eso adenocarcinoma
distal 1/3 eso
- pain or difficulty swallowing
- progressive weight loss
- hematemesis
- chest pain
- vomiting
eso adenocarcinoma
ca ass’d with:
- etoh and tobacco
- hot beverage consumption
- plummer-vincent syndrome
- poverty
- diets low in fruits and veggies
- AA’s
- Iran, central China, Hong Kong, Brazil, S Africa
sq cell carcinoma
MC site of sq cell ca of the eso
middle 1/3 of eso
upper 1/3 eso ca mets to…
cerivcal LNs
middle 1/3 eso ca mets to… (3 nodes)
mediastinal, paratracheal, and tracheobronchial nodes
lower 1/3 eso ca mets to…
gastric and celiac nodes
- dysphagia
- odynophagia
- eso obst
- alteration of diet
- weight loss
- tumor hemorrhage
- sepsis
- food aspiration
sq cell ca of eso
high amplitude contractions of the distal eso d/t loss of inner cirular lay and outer longitudinal layer of smooth mm contractions
nutcraker eso
repetitive, simultaneous contractions of the distal eso smooth mm
diffuse esophageal spasm
- result of portal HTN
- present in nearly 1/2 of cirrhosis pts
gastroesophageal varices
G cells
antrum, secrete gastrin
parietal cells
fudus and body, secrete acid
foveolar cells
cardia and antrum, mucin-secreting
- moderate edema and slight vascular congestion on histo
- foveolar cell hyperplasia
- corkscrew profiles
- epithelia proliferation
gastropathy and mild acute gastritis
NPs above basement membrane
active inflammation - seen in gastritis
- erosion of gastric mucosa
- pronounced neutrophilic infiltrate
- fibrin-containing purulent exudate in lumen
acute erosive hemorrhagic gastritis
ulcers ass’d with shock, sepsis, or severe trauma
stress ulcers
ulcers in proximal duodenum ass’d with severe burns or trauma
curling ulcers
gastirc, duoenal, and eso ulcers ass’d with intracranial dz; high incidence of perforation
cushing ulcers
multiple ulcers found anywhere in the stomach
stress ulcers
- submucosal aa that doesn’t branch properly
- aa is 10x the normal size of gastric capillaries
- common along lesser curvature near GE junction
Dieluafor lesion
- longitudinal stripes of edematous/erythmatous mucosa
- strips of less injured pale mucosa
- ass’d wit cirrohsis and systemic sclerosis
- usually idopathic
- can cause fecal occult or Fe def anemia
gastric antral vasular ectasia (GAVE)
MCC of chronic gastritis
H. pylori inf
MCC of diffuse atrophic gastritics (not ass’d with H. pylori)
autoimmune gastritis
less severe, more persistent nausea and abd pain, sometimes ass’d with vomiting
chronic gastritis
strain of H. pylori that colonizes the gastric body and causes multifocal atrophic gastritis
CagA expressing strains
most common site of H. pylori in the stomach
antrum
stain used to visualize H. pylori
warthin-starry silver stain
- acholrhydria
- vit B12 def
- edocrine cell hyperplasia
- reduced serum pepsinogen conc
- Abs to parietal cells n IF
- gastritis that spares antrum
autoimmune gastritis
principal agent of injury in autoimmune gastritis
CD4+ T cells directed against pareital cell components (esp the H+/K+ ATPase
- diffuse mucosal damage of the oxynitic mucosa w/in the body and fundus
- vitamin B12 def
- intestinal metaplasia (++ goblet cells and columnar absorptive cells)
- Abs to parietal cells and IF
autoimmune gastritis
- dense infiltrates of eosiniphils in the mucosa and muscularis usually in antral or pyloric region
- peripheral eosinophilia
- inrcreased serum IgE
eosinophilic gastritis
- MC in F
- nonspecific abd s/s
- thickened folds in stomach covered by small nodules with central ulceration
- affects entire stomach
- intraepithelial T lymphocytes
lymphocytic gastritis
- any gastritis that contains well-formed granulomas or aggregates of epitheliod MPs
- MCC is Chron’s dz
- narrowing and rigidity of gastric antrum
granulomatous gastritis
complication of chronic gastritis that causes chronic mucosal ulceration affecting the duodenum or stomach
peptic ulcer disease
3 things that almost all peptic ulcers are ass’d with
- H. pylori
- smoking
- NSAIDs
MC site of peptic ulcers
proximal duodenum
MC site of gastric peptic ulcers
lesser curvature near interface of body and antrum
heaped up margins
characteristic of ca
round/oval sharply punched-out defect
classic peptic ulcer
- epigastric burning or aching
- Fe def anemia
- pain 1-3 hr post meals
- worse at night
- releaved by milk or eating
- N/V, bloating, belching, wt loss
- back, ULQ, or chest pain
peptic ulcer
inf that can induce MALT and give rise to a B cell lymphoma
H. pylori gastritis`
- exuberant reative epi proliferation
- entrapment of epi-lined cysts
- can minic invasive adenocarcinoma
gastritis cystica
- excess TGF-alpha secretion
- irregular enlarged rugae in body and fundus
- hyperplasia of foveolar mucous cells
- elongated, cork-screw appearing glands w/ cystic dilation
- increased risk of gastric adenocarcioma
- often follows resp inf
Menetrier disease
- gastrin-secreting tumors
- common in SI or pancreas
- duodenal ulcers
- chronic diarrhea
- doubling of oxyntic mucosal thickness
Zollinger-Ellison syndrome
risk of polyp dysplasia correlates to _____
size
polyps larger than _____ should be resected and histologically examined
1.5 cm
- well circumscribed lesions with smooth surface
- single or multiple
- cystically dilated, irregular glands lined by flattened parietal and cheif cells
- ass’d with increasing use of proton pump inhibitors
fundic gland polyps
almost always occur on a background of chronic gastritis with atrophy and intestinal metaplasia
gastric adenoma
MC malignancy of the stomach
gastric adenocarcinoma
geographic arease iwht high incidence of gastric cancer
Japan, Chile, Costa Rica, Eastern Europe
familial gastric ca is strongly ass’d w/ LOF mutation of which tumor suppressor gene?
CHD1 (encodes e-cadherin)
sporadic intestinal-type gastric ca strongly ass’d with increased signaling of what pathway?
Wnt
- LOF is APC
- GOF in beta-catenin
bulky gastric adnenocarcioma tumors
tumor ass’d with intestinal morphology
gastric adenocarcinoma with diffuse infiltrative growth pattern are often composed of what kind of cells?
singnet-ring cells
cells with large mucin vacuoles that push the nucleus to the periphery
singnet-ring cells
- desmoplastic restion
- rugal flattening
- lintis plastica
gastric adenocarcinoma
MC site of GI carcinoid tumors
small intestine
- intramural or submucosal masses
- tan/yellow firm masses
- areas of uniform cells with scant, pink granular cytoplasm and a oval stipple nucleus
- synptophysin and chromogranin A positive
gastric carcinoid tumor
- cutaneous flushing
- sweating
- bronchospasm
- colicky abd pain
- diarrhea
- R sided cardiac valvular fibrosis
carcinoid syndrome (ileal carcinoid tumors)
progonosis of foregut carcinoid tumor
rarely met, cured by resection
prognosis of midgut carcinoid tumor
aggressive, worse outcome
MC mesenchyma tumor of the abdomen
GI stromal tumor (GIST)
MC site of GIST
stomach
- young F
- GIST
- paraganglioma
- pulmonary chondroma
Carney triad
most frequent of intestinal obstruction world-wide
hernias
MCC of intestinal obstruction in the US
adhesions
MCC of intestinal obst in kids
intussuseption
“watershed” regions in the intestine
splenic flexture, sigmoid colon, rectum
acute/chronic ichemia with overlying bacterial superinfection and enterotocin release can induce what?
pseudomembrane formation - looks like c.diff
- sudden onset cramping
- LLQ pain
- desire to deficate
- bloody stool or diarrhea
acute colonic ischemia
MC aquired GI emergency of neonates
necrotixing entrocolitis
- malformed submucosal and mucosal blood vessels
- MC in cecum or R colon
- usually presents after 6th decade
- minor link to Meckel’s diverticulum
- ectatic nests of tortuous vv
- significant bleeding
angiodysplasia
malasbsorption MCly presents as what?
chronic diarrhea
diarrhea with isontonic stool that persists during fasting
secratory
diarrhea tha results from excessive osmotic forces (like lactose intolerance)
osmotic
diarrhea following generalized failure of nutrient abs, ass’ with steatorrhea, and is releaved by fasting
malabsorptive
diarrhea d/t inflammatory disease w/ purulent, bloody stools
exudative
class II HLA-DQ2 or -DQ8 allele
celiac disease
- increased intraepithelial CD8+ T lymphocytes
- crypt hyperplasia
- villous atrophy
- increased numbers of plasma cells, mast cells, and eosinophils
- increased intraepithelial lymphocytes, esp in the villus
celiac disease
MC celiac disease-ass’d cancer
t-cell lymphoma
- immune dysregulation
- polyendocrinopathy
- enteropathy
- x-linkage (germ line mutation in FOXP3)
- dysfxnl Treg cells
IPEX in autoimmune enteropathy
inheratence pattern of continental lactase deficiency
autosomal recessive
- failure to thrive
- diarrhea
- steatorrhea
- oil red-O stain of intestinal epi
- acanthocytic red cells (burr cells)
- presents in infancy
- AR inheritance
abetalipoproteinemia
comma-shaped, gm (-) bact that causes cholera
vibro cholerae
- abrupt onset watery diarrhea and vomiting
- incubation period of 1-5 d
- rice-water stool
cholera
common of traveler’s diarrhea w/ flagellated bacteria
camylobacter jejuni
cause of reactive arthritis, primarily in pts with HLA-B27
Campylobacter
- watey diarrhea
- flu-like prodrome
- possible dysentery
campylobacter
gm -, unencapsulated, nonmotile, facultative anaerobes belonging to the enterobacteiaceae
shigella
shigella inf are mostprominent in the?
L colon
- 1 wk diarrhea, fever, abd pain
- diarrhea goes from watery to dysnteric phase
- s/s can last up to 1 mo
shigella
- sterile reactive arthritis
- urethritis
- conjunctivitis
- MC in HLA-B27 + men btwn 20 and 40
complications of shigella
infection is stongly ass’d with travel to India, Mexico, the Philippines, Pakistan, El Salvador, Haiti
Salmonella - Typhoid Fever
gallbladder colinization w/ salmonella
chronic carrier state
- can disseminate via lymph and BVs
- reactive hyperplasia of phagocytes and lymphoid tissue
salmonella typhi
- sharply delineatied, plateau-like elevations of peyer patches in terminal ileum
- oval ulcers oriented along the axis of the ileum
- enlarged slpeen
- scattered foci of parenchymal necrosis in the liver
samonella typhi
small, erythmatous maculopapular lesions seen on the chest and abdomen
rose spots - samlonella
what does yersina bind in host cells?
beta-1 integrans
- regional LN and peyer patch hyperplasia
- bowel wall thickening
- apthous-like erosions and ulcers
- granulomas
- prefer to inf ieum, appy, and R colon
- inf enhaced by Fe
yersinia
- N/V
- abd tenderness
- payer patch infaction w/ LN involvement
- pharyngitis
- arthralgias
- erythema nodosum
yersinia
MCC of traveler’s diarrhea
ETEC
strain of EHEC that causes large outbreaks, bloody diarrhea, HUS, and ichemic cholitis
O157:H7
E. coli strain that invades epi cells and causes acute self-limiting colitis
EIEC
EAEC’s mode of epi cell attachment
adherence fimbrae
anti-biotic ass’d pseudomembranous colitis
C. difficile
- pseudomembran
- dense NP infiltrates in lamina propria
- mucopurulent exudate > “volcano-like” eruptions
C. difficile
malabsorbtive diarrhea d/t impared lymphatic transport
Whipple dz
- malabsorption
- lyphadenopathy
- arthritis
- moany MPs in SI lamina propria
- argyrophilic rods in LNS
Whipple dz
Tripheryma whippelii
Whipple dz
PAS + acid-fast negative
T. whippelii
icosahedral virus with single stranded RNA genome that causes approx 1/2 of all gastroenteritis outbreaks world wide
norovirus
encapsulated virus with segmented, ds RNA genome that is a common cause of diarrheal mortality in 6-24 mo
rotavirus
- nematode
- human fecal-oral contamination
- larvae coughed up and swallowed
- eggs in stool
- can cause pneumonitis
Ascaris lubricoides
- fecally cont soil
- penetrate unbroken skin
- eggs hatch in intestine
- inf can persisit for life
- peripheral eosinophilia
strongloides
- hookworm
- larvae penetrate skin
- worms attach to durodenal mucosa and suck blood
- erosions, focal hemorrhage, and inflammatory infiltrates of GI
- eggs in fecal smears
- chronic inf can lead to Fe def anemia
Necator durodenale and Acylostoma duodenale
- pinworms
- perirectal mucosal depo of eggs
- dx via microscopic eval of tape
enterobius vermicularis
- adult worms in mesenteric vv
- can can bleeding and obst
schtosomiasis
- whipworm
- inf young children
- bloody diarrhea
- possible rectal prolapse
tricuris trichiura
- attach to intestinal mucosa via scolex
- no peripheral eosinophilia
- eggs shed in feces
- abd pain, diarrhea, nausea
- worm can get very large and cause obst
intestinal cestodes - tapeworms
- protazoan w/ chitin wall and 4 nuclei
- info ppl in india, mexico, and columbia
- flask-shaped ulcer
- can penetrate splenic BVs
- liver abcesses
entamoeba histolytica
- fecally cont water sources (rural streams)
- flagellated protozoans
- no intestinal wall invation
- dx via immunofluorescent detection in stool sample
giardia lamblia
- cause of chronic diarrhea in AIDs pt
- causes Na malabsorption, Cl secretion > watery diarrhea
- dx via oocytes in stool
- MC in ileum and prox colon, can get into resp tract in immunocomp hosts
cytosporidium
- peaks btwn 20-40 yo
- MC in F
- abd pain/discomfort at least 3 d per mo over 3 mo
- improves with defecation or change in stoll freq or form
IBS
- IBD
- limited to colon and rectum
- extends only into mucosa and submucosa
- p-ANCA +
ulcerative colitis
- IBD
- may involve any area of the GI trach
- transmural
- ASCA +
Crohn’s dz
IBD ass’d with NOD2 polymorphisms
Crohns
IBD ass’d with Th1 response
Crohns
IBD ass’d with ECM1 polymorphisms
ulcerative colitis
IBD ass’d with HNFA polymorphisms
ulcerative colitis
IBD ass’d with anti-flagellin antibodies
Crohns
- common in teriminal ileum, ileocecal valve, and cecum
- skip lesions
- apthous ulcer
- cobblestoning
- fissures
- creeping fat
- crypt abcesses
- abrupt ulceration transitions
- paneth cell metaplasia in L colon
- noncaseating granulomas (can be in the mesenteric LNs)
Chron’s
- always involves rectum w/ continuous leions
- broad-based ulcers
- pseudopolyps
- mucosal bridges
- risk of toxic megacolon
- limited to mucosa and submucosa
ulcerative colitis
- numerous mucosal lymphoid collicles
- histo looks like IBD
- possible granulomas
- occurs in diverted segment of bowels (MC in ulcerative colitis pts)
diversion colitis
- hematopoetic stem cell transplant
- epi apoptosis of crypt cells
- watery diahrreah
GVH dz
- small, flask-like outpouchings
- occur in regular dist along taeniae coli
- MC in sigmoid colon
sigmoid diverticular disease
- serrated surface architectiure
- mature goblit and abdoptive clls
- MC in L colon
- 6th decade of life
hyperplastic polyps
- inflammatory infiltrates
- erosion and epi hyperplasia
- lamina propria fibromuscular dysplasia
inflammatory polyps
SMAD4 mutation
juvenile polyps
LOF in STK11 gene
Peutz-Jeghers syndrome
dark blue/brown macules on lips, nostril, buccal mucosa, palmas surfaces of hands, genetalia, and paerianal region
Peutz-Jeghers syndrome
FAP inheritance pattern
AD
APC mutations
adenomatous polyposis
colorectal adeno ca devos in 100% of all untx pts with what dz?
FAP
inheratence pattern of MYH-ass’d polyposis
AR
MC form of syndromic colon cancer
hereditary non-polyposis colorectal cancer
MSH2, MSH1 mutations
HNPCC
MCC of maligancy of the GI tract
adenocarcinoma
“napkin-ring” constrictions
annular carcinomas in the distal colon
hallmark of adenomas that are precursors of colonic adenocarcinomas
cytologic dysplasia
pure sq cell carcinoma of the anal canal is ass’d with?
HPV inf
MC tumor of the appendix
neuroendocrine
dense fibrosis that may extend to involve the mesentary
sclerosing retroperitonitis
malignant tumor arising from the peritoneal lining
mesotheliomas - ass’d with asbestos exposure
t(11;22)(p13;q12)
desmoplastic small round cell tumor of the peritoneum
MC primary soft tissue tumor of the peritoneum
desmoplastic small round cell tumor
