Gastrointestinal Flashcards
Cleft lip and palate embryologic defect
Failure of the facial prominences to fuse
Bechet syndrome triad
REcurrent oral aphous ulcers
Genital Ulcers
Uveitis
Aphthous ulcer is composed of
granulation tissue
HSV1 remains dormant in which structure
Trigeminal ganglia
2 precursor lesions of sq cell carcinoma of mouth
Leukoplakia
Erythroplakia
How to differentiate Leukoplakia, thrush and hairy leukoplakia
Leukoplakia cannot be scraped away (thrush can)
Hairy leukoplakia is on LATERAL tongue and is hairy looking
4 organs affected by mumps
Bilateral parotids
Orchitis
Pancreatitis
Meningitis
Siladenitis presentation
unilateral parotid swelling
Siladenitis cause
Parotid stone –> S. aureus infection
Pleomorphic adenoma components
Stroma and epithelial tissue –> BIPHASIC
How to distinguish beign/malignant parotid gland tumors
Malignant tumors affect facial nerve
weakness, decreased lacrimation, salivation and taste
Pleomorphic adenoma recurrence rate
High b/c it has irregular borders –> incomplete resections
Cystic tumor with lymphoid tissue and germinal centers in the parotid
Warthin tumor
TE fistula presentation (4)
Vomiting and coughing with FIRST FEEDING
Abdominal distension
Polyhydramnios
Esophageal web is a protrusion of which layer
Esophageal mucosa only
Esophageal web presentation
dysphagia for solids
Zenker diverticulum layers
Mucosa only (false diverticlum)
Zenker location
b/w upper esophageal sphicnter and pharynx
Zenker presentation
Halitosis
“feels like lump in throat”
Dysphagia
Painful hematemesis in bullemic or alcoholic
Mallory Weiss
Mallory weiss defect
longitudinal of mucosa at Gastroesophageal junction
Subcutaneous emphysema w/ shoulder pain
Borhaave syndrome –> ruputred GE junction
Painless and Massive hemetemesis of bright blood
Ruptured esophageal varicies
Esophageal varicies veins
L gastric vein + azygos vein/esophageal vein
Dysphagia for solids + liquids with halitosis
Achalasia
Achalasia underlying defect
No ganglion cells in myenteric plexus = no VIP = no relaxation
Imaging findings in Achalasia
Dilated esophagus
Increased LES pressure
infectious cause of achalasia
Trypanasoma cruzi
HIatal hernia
Cardia of stomach herniates into esophagus–> GERD
Paraesophageal hernia
Cardia herniates lateral to esophagus, above diaphragm
“bowel sounds in the lung fields” is characteristic of
Paraesophageal hernia
Classic GERD presentation
Heartburn
Persistent cough
late complication of GERD
Ulceration w/ stricture
what causes strictures in GERD
loss of mucosa = loss of stem cells = fibrosis
specific cell changes that occur in Barrets Esophagus
Non Keratinized Stratified Squamous epithelium –> Non ciliated columnar epithelium w/ goblet cells
Adenocarcinoma of esophagus location
lower 1/3
3 major risk factors for adenocarcinoma
GERD
Hiatial Hernia
Barret Esophagus
Sq Cell carcinoma of esophagus location
Upper 2/3
3 classic presentations of esophageal cancer
Dysphagia for solids that progresses to liquieds
Hematemesis
Weight loss
Sq cell carcinoma has which unique symptom
Hoarseness and cough
cancer in upper 1/3 mets to which nodes
cervical nodes
cancer in lower 1/3 mets to
celiac / gastric nodes
Middle 1/3 mets to
mediastinal / tracheobronchial nodes
failure of the lateral folds of the ventral wall causes
Gastroschisis (not covered by peritoneum)
Omphalocele
Omphalocele is a failure of
Bowel to return to abdominal cavity from umbilical cord
non billous vomiting several weeks after birth + abdominal mass
Pyloric stenosis
Sever hypovelmia causing an ulcer is called
Curling ulcer
2 mechanisms by which NSAIDs cause gastritis
Decreased PGE2 = More acid, less mucus
Increased intracranial pressure causing ulcers is called
Cushing ulcer –> increased vagal stimulation = increased acid
erosion vs ulceration
erosion - epithelium only
ulceration = entire mucosa and beyond
autoimmune gastritis is which type of hypersensitivity
TYpe IV
where are parietal cells located
boidy and fundus
4 features of pernicious anemia
Mucosal atrophy
Achlorhydria
Megaloblastic anemia
Intestinal type gastric cancer
H pylori affects which area
pylorus, antrum
2 cancers H pylori increases risk for
Intestinal type adenocarcinoma MALT lymphoma(marginal zone)
2 tests to determine presence of H.pylori
+ urea breath test
Ag present in stool
Histology of H pylori
The align the mucosal cells but do not invade
Type of ulcers caused by h pylori
duodenal
How to differentiate b/w gastric and duodenal ulcer in HPI
duodenal = improved pain with meals (bicarb secreted)
Gastric = worse with meals (acid secreted)
2 complications of posterior duodenal ulcer rupture
gastroduodenal artery rupture
Pancreatitis
2 complication of gastric ulcer rupture
Left gastric artery rupture (on lesser curvature)
Intestinal type adenocarcinoma
3 risk factors for intestinal type gastric cancer
Chronic gastritis from any cause
Bllod group A (type A for cA)
Nitrosamines in bbq food
2 features of diffuse type gastric cancer
Signet ring cells
Desmoplasia –> linitis plastica
Patient develops tons of seborrhic keratoses within a week and acanthosis nigracans…suggestive of?
Gastric cancer
Left supraclavicular node enlargement is suggestive of
GI cancer…particularly Gastric
lymph node affected by intestinal type
periumbilical node
intestines are near the umbilicus
Bilateral ovary metastisis is common in which type of gastric cancer
diffuse
will see signet ring cells in ovary
billous vomit with duodenal distension
duodenal atresia
2 conditions associated with down syndrome
Duodenal Atresia
hirsprungs
meckel diverticulum layers
TRUE diverticulum. all layers are involved
2 embryonic correlations to meckel diverticulum
Persistent omphalomesenteric duct
Persistent viteline duct
most common cause of painless hematochezia in kids? adults?
Kids- meckel
Adults- diverticulosis
General rule for infarction/bloody diarrhea
Infarction = Bloody diarrhea!
2 MCC sites of volvulus
sigmoid in adults
cecum in kids
2 MCC of intususseption in kids
lymphoid hyperplasia (viral infection) Meckel divertisulum
Small bowel infarction ssx (3)
GENERALIZED abdominal pain
Bloody diarrhea
Decreased bowel sounds
Transmural vs mucosal small bowel infarcts (cause)
Transmural = thrombus
Mucosal = hypotension (same logic as subendocardial ischemia)
lactose intollerance pathogenesis
Lactase deficiency (disaccharidase, brush border ensyme)
Lactose intolerance biopsy
Normal!
Celiac dz HLA types
HLA DQ2 and DQ8
“i 8 2 much gluten at Dairy Queen”
3 Celiac auto Ab
IgA agasint gliadin
IgA against endomysium
IgA agasint tissue transglutaminase
Inflammatory cell responsible for tissue damage in celiac
CD4 T cells reacting to deamidated gliaden
Skin association w/ celiac
dermatitis herpetiformias
histology cause of dermatitis herpetiformis
IgA deposition at top of dermal papillae
3 features of biopsy in celiac
Flat villi
Crypt hyperplasia
Increased lymphocytes
area of bowel most affected by celiac
Duodenum
Cancer celiac pts are at increased risk for
T cell lymphoma…unique b/c most lymphomas are B cell
how to identify tropical sprue
same ssx as celiac but occurs in tropical region
Tropical sprue vs celiac zones of damage
Celiac = duodenum (fe def) Sprue = jejunum (folate def) and ilium (b12 def)
Fever, steatorrhea, joint pain, swollen lymph nodes
Whipple dz
Histology of whipples
PAS + foamy macrophages
Why does whipple cause steatorrhea
Macrophages compress lacteals –> fat mal absorption
3 extraGI sites that whipples affects
Cardiac valves
Arthritis (joints)
Nodes (lymph nodes)
“WHIPped cream in a CAN”
most common layer of GI wall affected by whipple
Lamina propria
Carcinoid tumor histology and stain
neurosecretory granules –> Chromogranin +
most common sites for primary carcinoid tumors
Terminal Ileum (will metastasize) Tip of appendix (won't metastasize)
Labs for carcinoid tumor
Increased 5Hydroxyindolacetic acid (b/c serotonin is metabolized by MAO)
Why does metastasis to liver cause carcnoid syndrome
bypass metabolism of serotonin by MAO
4 SSx of carcinoid syndrome
Flushing of skin
Diarrhea
Tricuspid insufficiency
Pulmonic valve stenosis
MCC of appendicitis in kids vs adults
Kids = lymphoid hyperplasia (just like intussuption) adult = fecalith
UC vs Chrons wall involvement
UC- mucosa/submucosa
Chrons = full thickness
UC vs Chrons location in GI
UC- colon only. loves the rectum
Chrons- Anywhere. Terminal ilium > Anus > Rectum
UC symptoms
LLQ pain with bloody diarrhea and urgency
Chrons symptoms
RLQ colicky pain (b/c transmural inflammation)
+/- blood
UC histology
Crypt abscesses with neutrophils
“Crypt for uC”
Chrons histology
Granulomas full of TH1 cells
UC vs Chrons gross appearance
UC- loss of haustra
Chrons- Creeping fat + strictures =string sign
2 major GI complications of UC
Toxic megacolon
Cancer
4 major GI complications of chrons
Malabsorption (B12, fat, vitamins)
Calcium oxalate stones
Gallstones (decreased bile acid resorption)
Fistula formation (peeing air!)
4 extraintestinal manifestations of BOTH IBDs
Rash (pyoderma gangrenosum)
Uveitis
Apthous ulcers
Seronegative spondyloarthritis
Unique extraintestinal complication of UC
Primary Sclerosing Cholangitis (p-ANCA)
smoking protects against
UC
hirshbrung defect
Failure of ganglion cells to descend into myenteric/submucsal plexus –> no VIP = no relaxation
Where do ganglion cells derive from?
Neural crest
3 clinical features of hirsprung
Failure to pass meconium
Empty rectal vault + mega colon
Explosive diarrhea after DRE
specifically, where do colonic diverticula arise?
Muscularis propria where the vasa recta enters
DDx for pneumaturia or stool in urine
Chrons or Diverticulosis
Angiodysplsia location and population
Right side of colon
Old people
hereditary hemorrhagic telangiectasia defect
Thin walled blood vessels in mouth / GI tract
HHT SSx
Telangectasia on lips
Diarrhea
HHT inheritance
Autosomal Dom
Ladd bands
FIbrous bands that connect colon and liver. Seen in malrotation
Malroation embryonic problem
Failure of midgut rotation
Malroation predisposes to
Volvulus / duodenal obstruction
Are adeonmatous polyps beign or malignant
Benign
how do adenomatous polyps become cancer
Adeonma- Carcinoma sequence
Adematous Polyposis Coli (APC) Gene mutation
Increased RISK of polyp
Which mutation leads to formation of polyp?
KRAS
2 mutations that cause polyp to become carcionma
Decrease p53
Increase COX2
which medication can help prevent movement from polyp to carcinoma?
ASA…inhibit Cox2
most dangerous growth pattern for a polyp
Sessile growth > Pedunculated
most dangerous histology subclass of polyps
Villous
“Villous is the Villan”
Familial Adematous Polyposis gene mutation and chromsome
APC mutation on Ch 5
“Familial on 5”
FAP inheritance
AD
osteoma, retinal defects, nasty teeth and FAP
Gardner Syndrome
“Gardeners get bone pain from being on their knees. Retinal defects from being in the sun, and bad teeth from all that chew”
FAP with medullablastoma or glioblastoma
Turcot Syndrome
“Turcot sounds like turban. Turbans go on heads”
Prolapsed mass in coming out of a kids butt
Hamartoma
Hyperpigmentation of lips and genitals + polyps in stomach and small intestine
Peutz Jeghers
Peutz Jeghers inheritance
AD
pathway by which right sided colon cancers arise
Microsatelite instability path
“MicRo is Right” or “RIGHTcro”
Microsattelite instability pathway defect and pathogenesis
CpG hypermethylation –> failed DNA repari
Family history of colorectal, breast, endometrial cancer
Hereditary nonpolyposis colorectal carcinoma
HNPCC mutation
DNA mismatch repair enzymes –> tumors arise from microsattelite instability pathway (right)
pathway by which left sided cancers arise
Adenoma Carcinoma Sequence
“Firing an AK53” APC –> KRAS –> p53
Left sided colon cancer SSx
Decreased stool caliber
+/- blood streaked stool
LLQ pain
Right sided colon cancer SSx
Fe deficiency anemia
Occult Blood
Vague pain
Most common site of metastasis for colon cancer
Liver
Serum tumor marker for colon cancer and its use
CEA. Used to measure for recurrence
How to differentate pure esophageal atresia from TE fistula + atresia
TEF+Atresia leads to air in the stomach on CXR
Pure atresia will be lacking that because there is no communication with the trachea
Position of gastroesophageal junction relative to diaphragm in a hiatal hernia
GE junction shifts upwards
Position of gastroesophageal junction relative to diaphragm in paraesophageal hernia
Normal. Only problem is the fundus of the stomach is in the thorax
Embryologic defect that predisposes to hiatal hernias
Defective pleuroperitoneal membrane
How to differentiate mallory weiss from borehave histologically
Mallory weiss is only mucsosal tears
Borehave is transmural`
Pt with reflux symptoms that has not improved with a PPI. He has a history of asthma. Dx?
Eosinophilic Esophagitis
Which risk factor increases risk for both squamous and adenocarcinoma of the esophagus
Smoking
Failure of the caudal ventral wall to fuse in utero
Bladder extrophy
type of hypersensitivity rxn in pernicious anemia
Type IV
histology shows mucin filled cells with peripheral nuclei
Signet Ring Cells
Which gland type is hypertrophied in duodenal ulcers?
Brunner Glands –> benign
Pt with hx of epigastric pain that improves with eating presents with severe abdominal pain and shoulder pain. CXR reveals air under the diaphragm
Perforated duodenal ulcer
Imaging shows hypertrophied rugae of the stomach with excess mucus production
Menetrier Disease…rugae look like brain gyri
Menetrier Disease defect
Excess mucus production leading to protein loss and parietal cell atrophy –> achlorhydria
Patient has small bowel infarction, then develops abdominal pain, flatulence and diarrhea when he drinks milk. Why?
Lactase is very sensitive to ischemia, so patients with abdominal ischemia or trauma often have temporary bouts of lactose intolerance
Celiac and IgA deficiency often occur together. What is the serum marker for celiac if someone is IgA deficiency?
IgG Ab against gliaden, tTG and endomysium
Main complication of pyloric stenosis
Metabolic alkalosis (hypokalemic, hypochloremic)
Best initial test to confirm the presence of malabsorption in a patient. Not necessarily the specific cause
Sudan stain for fecal fat
Besides dermatitis herpetaformis, what is a major extraGI manifestation?
Low bone density
Basis of the D-xylose test
Xylose should be reabsorbed in proximal small intestine (blood and urine levels will increase)
Xylose test in Celiac
Blood and urine xylose levels will be low because you cant reabsorb it (villi are all destroyed)
3 Lactose intolerance screening tests
Elevated hydrogen breath test
Acidic stool
Increased stool osmoality
Why is the stool acidic in lactose intolerance/
Bacteria convert lactose into short chained fatty ACIDS (which also release H+ and cause a positive breath test)
Abdominal distension and diarrhea with a megaloblastic anemia. Improves with Antibiotics
Tropicle sprue
What 2 substances to enteric bacteria produce?
Vitamin K and Folate
This is why neonates can develop vitamin K deficiency! They don’t have gut flora yet
What 4 things do enteric bacteria consume
Vitamins A,D,E
B12
Iron
Bile Salts
Who is bacterial overgrowth most often seen in
Bypass surgery patients
Patient presents with sudden onset severe epigastric pain. PE is unremarkable and no abnormal imaging findings. Diagnosis?
Acute mesenteric ischemia
“Pain is out of proportion to physical findings”
DDx for failure to pass meconium. How to differentiate between them?
Meconium Ileus (CF) --> no stool after DRE Hirshprungs --> Explosive stool after DRE
SSx of bowel obstruction
No flatulence or bowel movements
Tympanic to percussion
Decreased bowel sounds
Intermittent vomiting, abdominal pain and obstruction in a child that spontaneously improves, then happens again. Imaging shows improper positioning of the large bowel and fibrous tissue connected to liver
Malrotation (Ladd Bands connect colon to liver)
Malrotation embryo defect
Abnormal midgut rotation
2 complications of malrotation
Volvulus
Duodenal obstruction
Streptococcal gallolyticus is associated with
Endocarditis in colon cancer (formerly called S. bovis)
MLH1 mutation
HNPCC
What is another name for the adenoma carcinoma sequence?
Chromosomal instability pathway
Premature infant with fever, bloody diarrhea and abdominal distension and free air in the abdominal cavity
Necrotizing enterocolitis
Abdominal xray looks like monkey bread w/ all the air in there
Necrotizing enterocolitis most commonly happens in which types of infants
Purely formula fed babies
