What are the microscopic features of a bronchogenic cyst?
pseudostratified columnar epithelium with cillia
What are the microscopic features of a duplication cyst?
Must have muscle layer! Usually squamous mucosa BQ! Closed relationship with main esophagus
What are common causes of achalasia? BQ! What organism can cause achalasia?
not common primary, usually secondary - defined by saccular dilitation - Scleroderma, Amyloidosis, Chagas - "SAC"
Organism? Trypanosoma cruzi from South America Glass side has been on board--lymphoid aggregates infiltrating myenteric plexus on glass slide
1. What is the most common cause of ulceration in the GI tract?
2. BQ! What anatomic location is the most common site for pill esophagitis?
3. BQ! Most common medication associations with pill esophagitis/gastritis?
1. Reflux (GERD) is number one cause of ulceration in GI
2. This is more common mid esophagus where aorta crosses over! Expect to see ulcer with pill esophagitis--foreign material hopefully polarized or birefringent
3. Iron very common etiology - esp stomach Alendronate - bone resorption
BQ! Etiology of esophageal SCC?
Tobacco, alcohol, vitamin A deficiency and zinc (aging population)
BQ! Esophageal squamous cell carcinoma can be associated with what rare autosomal dominant syndrome?
Palmaris et plantaris disseminata
Approx 1/3 will have esophageal carcinoma
What molecular alterations are found in esophageal adenocarcinoma?
Aneuploidy, loss of heterozygosity, mutation of p53, c-erbB-2 oncogene expression is present
What are the best predictors of survival for esophageal adenocarcinoma?
Depth of mural invasion, lymph node or distant metastasis
What does H pylori produce which enhances its binding to a certain blood group type?
urease and adhesion production--enhanced binding of blood Group O
What is Type A gastritis?
5% of gastritis, diffuse corporal gastritis, immune mediated (antiparietal and anti intrinsic factor Abs), high serum gastrin, F>M, low vitamin B12, H. pylori
What is Type B gastritis?
Multifocal atrophic gastritis, not immune mediated, normal or low serum gastrin, F=M, normal Vitamin B12, H. pylori 90-100%
BQ! What are some of the differences between fundic gland polyps secondary to PPI use and fundic gland polyps in someone with FAP syndrome?
PPI predisposes to fundic gland polyps, usually single or multiple, less than 1% dysplastic, have beta-catenin mutations
FAP syndrome usually multiple, large, 40% dysplastic BUT DO NOT PROGRESS to ADENOCARCINOMA usually, young patients, APC gene mutation
What is the mutation seen in Peutz-Jeghers? They have increased risk for what cancers?
Autosomal dominant, STK11/LKB1 mutation at 19p13 Increased risk for:
"PASS Boards"--Pancreatic adenoca, Adenoma malignum of cervix, Sertoli cell tumor, SCTAT, Breast carcinoma
How to distinguish inflammatory fibroid polyps from GIST?
Not cellular enough to be GIST, too many eosinophils, onionskins around vessels, CD34 positive CD117 negative except for MAST cells, usually 2-5 cm can be LARGE 11 cm, PDGFR mutation positive
What are the 3 types of gastric carcinoid and what are their associations?
Type I - type A gastritis
Type II - MEN, zollinger ellison
Type III - sporatic more aggressive, less amenable to resection, usually SINGLE, higher mitotic rate
*Type I and II are less aggressive because if you remove the gastrin stimulus, the carcinoid will go away. Sporadic ones should be treated as possibly malignant.
What are the staining characteristics of GIST?
90% positive CD117 look for MAST cells
10% S100 - not always schwannoma - LOOK For lymphoid cuffing to call it schwannoma
Criteria for grading GIST?
● Low mitotic rate: 5 or fewer per 50 HPF
● High mitotic rate: over 5 per 50 HPF
TX: Primary tumor cannot be assessed
T0: No evidence for primary tumor
T1: Tumor 2 cm or less
T2: Tumor more than 2 cm but not more than 5 cm
T3: Tumor more than 5 cm but not more than 10 cm
T4: Tumor more than 10 cm in greatest dimension
Stage IA: T1-2 N0 M0 low mitotic rate
Stage IB: T3 N0 M0 low mitotic rate
Stage II: T1-2 N0 M0 high mitotic rate or T4 N0 M0 low mitotic rate
Stage IIIA: T3 N0 M0 high mitotic rate
Stage IIIB: T4 N0 M0 high mitotic rate
Stage IV: N1 or M1
BQ! What is the most common protozoal infection in the US?
Giardia is most common protozoal infection in USA
5% of usa have it
In the world? Amoeba most common by worldwide standard 10%
What is the differential diagnosis when you see macrophages in the small bowel?
Mycobacterium avium intracellular vs Whipples
What organism causes Whipple's disease? BQ! Where are the organisms located?
Tropheryma whipplei bacteria IN MACROPHAGES and in the lamina propria! (not only in macrophages) Stain with PAS-D!
Even patient's after therapy will be positive so be careful! Need to use PCR to test after treatment. MAI can also be positive for PAS-D but the organisms look very different
What infectious agent is shown here ?
BLUE BLEBS on surface of mucosa
Found in crypts, gallbladder and intestine
It is a coccidio infection usually animal infection, more in immunocompromised
What parasitic GI infection is endemic to Kentucky and Eastern Tennessee?
Can live as larval form for years, is an eosinophillic rich disease; however there are higher eosinophils in southern region anyway
hyperinfection filariform larvae - upper right
BQ! What is the Splendore-Hoeppli phenomenon?
Radiating or anular eosinophilic deposits of host-derived materials (Charcot Laden crystals) and possibly of parasite antigens, which form around fungi, helminths, or bacterial colonies in tissue
What is diaphragm disease and what causes it?
Use of slow release NSAIDS may lead to this peculiar form of strictures called diaphragm disease in the small bowel (terminal ileum)
Characterized by strips of fibrosis perpendicular to lumen
BQ! What is gluten sensitive enteropathy?
Systemic autoimmune disorder induced by exposure to gliadin or prolamin graction of gluten proteins in wheat, barley, rye, etc.
BQ! Is gluten sensitive enteropathy always a diagnosis of kids?
NO! Adults can develop it from adenovirus 12 exposure E1B protein which has alpha gliadin crossreaction--sensitizes the T cells so patient can develop gluten sensitive enteropathy
What is refractory sprue?
Celiac patients that stop responding to diet restrictions. Normal IELs should be both CD3 and CD8 positive. If the IELS are CD3+ and CD8-, sign they are developing refractory sprue which puts them at risk for EATL - enteropathy associated T-cell lymphoma
BQ! What do you see in tissue specimens from patients with Waldenstrom macroglobulinemia?
Deposit IgM in mucosa, can be PASD positive--deposits pink accellular material and Congo red neg
What is goblet cell carcinoid?
Specific to appendix, prognosis between carcinoid and adenocarcinoma - more aggressive prognosis Suggested term--adenocarcinoid, older than 30 with acute appendicitis
What is a small bowel tumor with psammoma bodies and is associated with NF1?
Also called psammomatous carcinoid--EXCLUSIVELY in the periampullary region
Commonly misdiagnosed as adenoCA, near ampulla of vater, glandular appearance, large
LOOK FOR PSAMMOMA BODIES
May not be somatostatin positive, physiologic effect vs stain, cut deeper - synaptophysin, neurofibromatosis I syndrome association