GIT Flashcards
MC form of congenital intestinal atresia
Imperforate anus
MC congenital anomaly of the GIT
Failed involution of vitelline/omphalomesenteric duct
Meckel Diverticulum
Associations of Pyloric Stenosis
Turner syndrome
Trisomy 18
Erythromycin, Azithromycin exposure in 1st 2 weeks of life
Absence of Myenteric (Auerbach) and Submucosal (Meissner) d.t. ABNORMAL MIGRATION of neural crest cells or premature death
failure to pass meconium
abdominal distention
Hirschsprung disease
RET mutations
Complications of Hirschsprung disease
enterocolitis
fluid and electrolyte imbalance
perforation –> peritonitis
MC functional esophageal obstruction
Nutcracker esophagus
Triad of Achalasia
incomplete LES relaxation
increased LES tone
esophageal aperistalsis
MCC of esophageal varices
liver cirrhosis
2nd MCC - hepatic schistosomiasis
Complication of chronic GERD characterized by intestinal metaplasia within squamous epithelium
GOBLET CELLS - HALLMARK
increased risk of esophageal ADENOCARCINOMA
Barrett’s esophagus
More common
MIDDLE 3rd
squamous dysplasia
tobacco and alcohol
previous radiation
diet low in fresh fruits and vegetables
hot drink ingestion
achalasia
Plummer Vinson syndrome
Squamous Cell Ca (Esophagus)
DISTAL 3rd
Barrett’s esophagus
chronic GERD
tobacco
radiation exposure
PROTECTIVE - H. pylori
Adenocarcinoma (Esophagus)
MCC of chronic gastritis
H.pylori gastritis
Morphology of Ulcers
solitary (80%)
sharply punched out defects
mucosal margin level with surrounding mucosa
heaped up margins - MALIGNANCY
Abnormal SUBMUCOSAL arteriole
w/n LESSER curvature near GEJ
DIEULAFOY LESIONS
Longitudinal stripes of edematous, erythematous, mucosa
Gastric Antral Vascular Ectasia (GAVE)
Diffuse foveolar hyperplasia + protein losing enteropathy
d.t. excessive TGF-a secretion
Menetrier Disease
Diffuse foveolar hyperplasia + protein losing enteropathy
d.t. excessive TGF-a secretion
Menetrier Disease
Caused by gastrin-secreting neuroendocrine tumors
Zollinger Ellison Syndrome
TRIAD:
pancreatic islet tumors
gastric hypersecretion
PUD
MC gastric polyp
Inflammatory/Hyperplastic polyps
Polyp associated with PPI use
Fundic gland polyps
Associated with chronic gastritis with atrophy and intestinal metaplasia
Gastric adenoma
MC malignancy of the STOMACH
Adenocarcinoma
ANTRUM - MC site
MC site of extranodal lymphomas
Stomach
MC mesenchymal tumors of the abdomen
GIST
Risk Factors of Gastric Adenocarcinoma
Chronic Atrophic Gastritis
Ingestion of N-nitrosocompounds and benzo(a)pyrene
Most important prognostic factors in Gastric Adenocarcinoma
depth of invasion
nodal/distal metastases
LIVER - MC sites of metastasis
Tumors of neuroendocrine origin
intense desmoplasia
(+) synaptophysin
(+) chromogranin
NEUROENDOCRINE NEOPLASMS
SI - MC site
Cytogenetic origin of GIST
CD117 - immunohistological marker
interstitial cells of Cajal
Carney’s Triad
GIST
paraganglioma
pulmonary chondroma
MCC of intestinal obstruction
Adhesion
MCC of intestinal obstruction in children <2
Intussusception
MC site of ischemic bowel disease
COLON
WATERSHED AREAS (termination of the blood supply)
splenic flexure
colon
rectum
Seen in Lactase Deficiency
Osmotic Diarrhea
Seen in Celiac disease - cell mediated immune enteropathy
Malabsorptive Diarrhea
Isotonic stools seen in Cholera
Secretory Diarrhea
Purulent, bloody stools seen in amebic dysentery
Exudative Diarrhea
Common extraintestinal manifestations of IBD
migratory polyarthritis
ankylosing spondylitis
uveitis
skin lesions
Most feared long term complication of UC and colonic CD
colitis associated neoplasia
Common Histologic Changes in IBD
inflammatory infiltrates
crypt abscesses
crypt distortion
pseudopyloric epithelial metaplasia
Hallmark of CD
Noncaseating granulomas
transmural
ileum + colon
rectal sparing
SKIP lesions
deep, knife like ulcers
marked lymphoid reaction, fibrosis, serositis
granulomas
fistula
fat/vitamin malabsorption
malignant potential - if with colonic involvement
recurrence after surgery - common
CROHNS DISEASE
mural
colon
superficial broad based ulcer
marked pseudopolyps
(+) malignant potential
smoking and appendectomy protective
toxic megacolon
ULCERATIVE COLITIS
Familial Adenomatous Polyposis (FAP)
adenocarcinoma develops in 100% of untreated patients often before age 30 and nearly always by age 50
adenomatous polyposis coli (APC) gene Ch5
at least 100 polyps
MC site of juvenile polyps
RECTUM
Multiple
(+) risk of malignant transformation
pulmonary AVMs - extraintestinal lesions
JUVENILE POLPYS
mixed inflammatory infiltrate with cystically dilated glands
AD
SI - MC site
multiple GI hamartomatous polyps and mucocutaneous hyperpigmentation
increased risk of malignancy
PEUTZ JEGHERS POLYP
arborizing network and normal looking glands
Guardian/Gatekeeper of Colonic Neoplasia
APC
Hereditary Non-Polyposis Colon Cancer (HNPCC)
MSH2, MLH1
AMSTERDAM CRITERIA (3-2-1)
3 members (at least 1 should be a 1st degree relative of the other 2 and FAP should be ruled out already)
2 generations
1 diagnosed under age 50
The most important characteristic that correlates with malignancy in neoplastic polyps
SIZE
>4 cm - w/ foci of invasive cancer
MC malignancy of the GIT
Colorectal adenocarcinoma
LIVER - MC site of metastasis
Prognostic factors for colorectal adenocarcinoma
depth of invasion
LN metastasis
Proximal (Right) Sided Colon Cancers
BULKY, EXOPHYTIC masses
IDA
weakness
fatigues
Distal (Left) Sided Colon Cancers
ANNULAR “napkin ring” morphology
CHANGE IN BOWEL HABITS
Bowel obstruction
MC tumor in the APPENDIX
Well differentiated NET (carcinoid)
TIP; benign
Pseudomyxoma peritonei (MUCINOUS ASCITES) - occurs when appendix is ruptured
