Pathology - gi

Question 1

Salivary gland tumors

Answer 1

adenoma - painless, mobile, recurs easily
carcinoma - malingant! mucinous and squamous
Warthin - benign, cystic, germinal centers

Question 2

Achlasia cause

Answer 2

loss of myenteric plexus –> failure of relaxation of LES

progressive obstruction to solids AND liquids

incr. risk of esophageal SCC

may arise due to Chagas or malignancies

Question 3

Boerhaave vs. Mallory-Weiss

Answer 3

transmural (leads to pneumomediastinum) vs. mucosal laceration

Question 4

Esophageal strictures association

Answer 4

lye ingestion, acid reflux

Question 5

Immunocompromised esophageal lesions

Answer 5

Candida: white pseudomembrane
HSV-1: punched-out ulcers
CMV: linear ulcers

Question 6

Plummer-Vinson syndrome triad

Answer 6

Dysphagia, Iron deficiency anemia, Esophageal web

Question 7

Barrett esophagus metaplasia

Answer 7

replacement of non-keratinized stratified squamous epithelium with non-ciliated columnar with goblet cells

Question 8

Esophageal adenocarcinoma vs. SCC

Answer 8

adenocarcinoma: more common in US, fat, GERD

SCC: more common worldwide, alcohol, diverticula, esophageal web, hot liquids

Question 9

Causes of acute gastritis

Answer 9

NSAIDs

Burns: decr. plasma volume leads to decr. mucosal barrier

Brain injury: incr. vagal stimulation, incr. Ach, incr. acid production

Question 10

Type A chronic gastritis

Answer 10

Autoimmune disorder characterized by autoantibodies to parietal cells in the fundus/body

Question 11

Type B chronic gastritis

Answer 11

caused by h. pylori bacteria

Question 12

Menetrier disease

Answer 12

gastric hyperplasia leads to rugae hypertrophy, excess mucus production and decr. acid production

PRECANCEROUS

Question 13

Gastric cancer associations

Answer 13

Acanthosis nigricans
early local spread (liver mets)
lesser curvature (intestinal)
signet ring cells, mucin filled (diffuse cancer)
linitis plastica (diffuse cancer)

Virchow node
Krukenberg tumor
Sister Mary Joseph nodule

Question 14

increased gastric acid secretion leads to…

Answer 14

Duodenal ulcers (not gastric!)

Question 15

Location of hemorrhage in ulcers

Answer 15

gastric ulcer on lesser curvature = left gastric artery

duodenal ulcer on posterior wall = gastroduodenal artery

Question 16

Duodenal ulcer perforation

Answer 16

free air under diaphragm

referred pain to shoulder via phrenic nerve

Question 17

Celiac disease associations

Answer 17

HLA-DQ2/DQ8

decreased bone density, dermatitis herpetiformis (papulovesicular skin rash, IgA deposits)

incr. risk of T cell lymphoma

marked atrophy of intestinal villi

Question 18

Vitamins lost with pancreatic insufficiency

Answer 18

Malabsorption of A, D, E, K and B12

test with d-xylose absorption test: normal urinary excretion w/ pancreatic insufficiency, decreased excretion with intestinal mucosa defect (decr. glucose absorption)

Question 19

Tropical sprue

Answer 19

Responds to antibiotics!

affects small bowel

Question 20

Whipple disease

Answer 20

foamy/distended macrophages with PAS-positive granules in intestinal lamina propia

Also, cardiac symptoms, arthralgias, neurologic symptoms

most often in older men

Question 21

Crohn’s gross morphology, micro, complications, extraintestinal, treatement

Answer 21

Skip lesions throughout GI tract, rectal sparing

Transmural inflammation, cobblestone mucosa, creeping fat, Noncaseating granulomas (Th1 mediated)

Strictures (leading to partial obstruction), fistulas

Migratory polyarthritis

Tx: steroids, azathioprine, antibiotics

Question 22

Ulcerative colitis gross morphology, micro, complications, extraintestinal, treatement

Answer 22

Colonic only! Always with rectal involvement

Loss of haustra, only mucosal/submucosal

Crypt abscesses w/ neuts, Th2 mediated

assoc. PSC, toxic megacolon, colon cancer
Look for pyoderma gangrenosum

tx: 5-ASA (mesalamine), 6-MP

Question 23

Causes for appendicitis in adults and children

Answer 23

Adults: fecalith
Children: lymphoid hyperplasia

Question 24

False diverticula

Answer 24

only mucosa and submucosa outpouch

occur especially where vasa recta perforate muscularis externa

ex. Zencker diverticulum

Question 25

Most common cause of LLQ pain

Answer 25

Diverticulitis

Question 26

Histologic subtypes of colonic polyps

Answer 26

Hyperplastic - non-neoplastic, rectosigmoid area Hamartomous - non-neoplastic, normal colonic tissue with distorted architecture Adenomatous - **neoplastic**, chromosomal instability with APC/KRAS mutations, villous worse than tubular, >4cm = malignant, <1cm = benign Serrated - premalignant, CpG hypermethylation with BRAF mutations, saw-tooth pattern of crypts

Question 27

Polyposis syndromes

Answer 27

FAP - APC mutation (chromosomal instability), Ch. 5q, chromo Gardner syndrome - FAP + bone tumors + hypertrophy of RPE + impacted teeth Turcot syndrome - FAP + malignant CNS tumor Peutz-Jeghers - hamartomas throughout GI tract + hyperpigmentation + incr. risk of cancer everywhere Juvenile polyposis syndrome - hamartomas in children

Question 28

Lynch syndrome

Answer 28

DNA mismatch repair defect leads to microsatellite instability 3 relatives w/ Lynch syndrome, 2 generations, 1 diagnosis before 50

Question 29

Colon cancer locations

Answer 29

rectosigmoid > ascending > descending Ascending (right) - exophytic mass, iron deficiency anemia, weight loss, more likely to bleed Descending - infiltrating mass, partial obstruction, colicky pain, hematochezia, more likely to cause obstruction

Question 30

Order of gene events in colon cancer

Answer 30

AK-53 Loss of APC (tumor supressor), gain of KRAS (protooncogene), loss of p53 (tumor suppressor)

Question 31

Cirrhosis histology

Answer 31

diffuse bridging fibrosis | nodular regeneration via stellate cells

Question 32

Ceruloplasmin

Answer 32

Copper-carrying protein decr. in Wilson's disease (copper accumulates in the liver and fails to be incorporated into ceruloplasmin during synthesis)

Question 33

Reye syndrome

Answer 33

viral infection (VZV/influenza B) that is treated with aspirin (whose metabolites reversibly inhibit B-oxidation) look for mitochondrial abnormalities, fatty liver, hypoglycemia, vomiting, hepatomegaly, coma

Question 34

Progression of alcoholic liver disease

Answer 34

Hepatic steatosis --> alcoholic hepatitis --> alcoholic cirrhosis ``` Cirrhosis = hepatic/biliary injury + loss of function Prognosis = serum albumin levels, PT time ```

Question 35

AST and ALT levels in alcoholic vs. fatty liver disease

Answer 35

AST > ALT: alcohol (ast = toast) ALT > AST: fatty liver (L = lipids)

Question 36

treatment for hepatic encephalopathy

Answer 36

lactulose rifaximin - antibiotic note: HE can be precipitated by blood/hemoglobin in the gut, which is converted into ammonia and absorbed into the bloodstream

Question 37

Other liver tumors

Answer 37

cavernous hemangioma - most common, spongy and benign liver tumor, DON'T biopsy hepatic adenoma - uncommon solitary mass, OCP or steroid use, may regress or rupture, look for sheet of cells angiosarcoma - exposure to arsenic or vinyl chloride mets from lung/breast

Question 38

Budd-Chiari syndrome associations

Answer 38

hypercoagulable states, polycythemia, post-partum, HCC | thrombosis or congestion of the hepatic vein w/o JVD

Question 39

alpha-1 antitrypsin deficiency

Answer 39

midfolded gene product aggregates in hepatocellular ER leading to cirrhosis look for panacinar emphysema as well

Question 40

Unconjugated vs. conjugated hyperbilirubinemia

Answer 40

Unconj: hemolytic, congenital, newborn, Crigler-Najjar, Gilbert Conj: biliary tract obstruction, biliary tract disease, excretion defect, Dubin-Johnson, Rotor

Question 41

Crigler-Najjar vs. Gilbert

Answer 41

absent UDP-glucoronosyltransferase vs. mildly decr. incr. unconj bilirubin CJ Type II is less severe and may be treated with phenobarbital (incr. liver enzyme synthesis)

Question 42

Dubin-Johnson vs. Rotor

Answer 42

DJ: defective liver excretion of bilirubin glucoronides across canalicular membrane, grossly black liver Rotor: milder, no black liver

Question 43

Wilson's associations

Answer 43

ATP7B gene sx: hemolytic anemia, basal ganglia degeneration, asterixis, dementia, dyskinesia, dysarthria tx: chelation w/ penicillinamine, trientine, oral zinc

Question 44

Hemochromatosis triad

Answer 44

Cirrhosis + diabetes + skin pigmentation look for heart failure and testicular atrophy HFE gene mutation (HLA Class I like molecule) - overabsorption of iron in the gut and iron overload in tissues women present later than men due to menstrual bleeding

Question 45

Hemochromatosis labs

Answer 45

Incr. ferritin, iron Decr. TIBC (transferrin is saturated) HLA-A3

Question 46

PBC vs. PSC histology

Answer 46

PBC: lymphocytic infiltrate and granulomas, destruction of intralobular ducts (middle-aged women, AMA) PSC: onion skin bile duct fibrosis, alternating strictures and dilation, beading of intra/extrahepatic ducts on ERCP (young men with IBD, MPO, p-ANCA)

Question 47

2 types of gallstones

Answer 47

Cholesterol (80%) - obesity, Crohn's, decreased 7a-hydroxylase activity Pigment black: radiopaque, Ca, hemolysis brown: radiolucent, infection

Question 48

Activation of biliary colic

Answer 48

Neurohormonal eg. CCK secretion

Question 49

Gallstone ileus

Answer 49

Fistula from gallbladder to small intestine leads to passage of stone into lumen, allowing for obstruction at the ileocecal valve

Question 50

most common primary infection of gallbladder

Answer 50

CMV

Question 51

Causes of acute pancreatitis

Answer 51

Gallstones, ethanol, trauma, steroids, mumps, autoimmune disease, scorpion sting, hyperTGs, ERCP, drugs (sulfa, NRTIs, protease inhibitors) Look for calcifications! Fatty acids bind calcium salts

Question 52

Pancreatic adenocarcinoma associations

Answer 52

disorganize glandular structure with cellular infiltration CA 19-9 tumor marker abdominal pain radiating to back migratory thrombophlebitis (Trousseau syndrome) obstructive jaundice with palpable, nontender gallbladder (Courvosier)

Question 53

Carcinoid syndrome

Answer 53

if intestinal-limited: not many symptoms due to first-pass through liver. Symptoms arrive with mets to liver enterochromaffin cells - APUD system (amine precursor uptake and decarboxylation)

Question 54

Diffuse esophageal spasm

Answer 54

Periodic, non peristaltic contractions of the esophagus Painful! Can clinically manifest with a chest pain similar to angina pectoris Intermittent dysphagia and occasional chest pain

Question 55

Acute hepatitis syndrome

Answer 55

All three have the same presentation: malaise, fever, skin rash, lymphadenopathy, then anorexia, RUQ pain, jaundice Histology: panlobular lymphocytic infiltrates, ballooning hepatocytes, hepatocyte apoptosis/necrosis Hep C is milder and can be asymptomatic

Question 56

Hyperestrinism in cirrhosis

Answer 56

Decr. metabolism of ansdrostenedione --> incr. circulating estrogens Also, incr. synthesis of SHBG --> incr. binding of testosterone Results in gynecomastia, spider angiomata, testicular atrophy, decreased body hair