Gastrointestinal

Question 1

What is the most common cause of blind-ending in the small bowel of a neonate?

Answer 1

Intra-uterine ischemic event. Not a congenital defect but rather an ischemic even that lead to the death of a section of small bowel. Usually the jejunum-ileum junction.

Question 2

Which type of GI neoplasm causes a secretory diarrhea?

Answer 2

Villous Adenoma

Question 3

Which bilirubin deposits in the brain?

Answer 3

Unconjugated

Question 4

From which of the two buds, ventral or dorsal, does the main pancreatic duct come from?

Answer 4

Ventral

Question 5

What are the signs and symptoms of Wilson disease?

Answer 5

It is caused by impaired Cu met in the liver resulting in high plasma values. Liver (elevated AST/ALT, acute or chronic hepatitis, portal HTN) and in the CNS (ataxia, parkinsonian tremor, slurred speech, depression, paranoia, Kayser-Flaischer rings)

Question 6

Describe carcinoid syndrome and its symptoms. What is it treated with?

Answer 6

5-HT secreting tumor (usually from the gut) that causes facial flushing, bronchospasm, diarrhea and hypotension. Use Octeotride, a somatostatin inhibitor that decreases secretion of GI hormones. Also used in VIPomas.

Question 7

Gastrointestinal foamy enterocytes, steatorrhea and failure to grow are signs of?

Answer 7

Abetalipoproteinemia, an inability to create ApoB48 (Chylomicrons) and therefore fat is stuck in the enterocyte.

Question 8

How may calories per gram of protein?

Answer 8

4

Question 9

What is Gilbert Syndrome?

Answer 9

A deficiency in UDP-glucuronosyltransferase which causes an unconjugated hyperbilirubinemia with no other symptoms.

Question 10

What is Dubin-Johnson Syndreom?

Answer 10

A deficiency in bilirubin transporters that causes a conjugated hyperbilirubinemia and a black liver with no other symptoms.

Question 11

Which arteries supply the lesser curvature of the stomach?

Answer 11

Right (distal, from the common hepatic) and Left (proximal, from the celiac) gastric arteries

Question 12

Which arteries supply the greater curvature?

Answer 12

Left and Right gastroepiploic

Question 13

What is the antidote for arsenic, mercury and gold poisoning?

Answer 13

diMERcaprol (chelating agent), succiner

Question 14

What is the most likely outcome of a Hep C infection?

Answer 14

Seen in IVDU it can lead to Stable Chronic Hepatitis. The second most common outcome is Chronic Hepatitis leading to Cirrhosis.

Question 15

What is the pathophysiology of gallstones in pregnancy?

Answer 15

Estrogen induced cholesterol secretion and progesterone induced gallbladder hypomotility.

Question 16

What is the major difference in labs for high infectivity chronic HBV versus low infectivity?

Answer 16

High infectivity is HBeAg positive while low infectivity is Anti-HBe positive.

Question 17

What is the most likely organ damaged in a patient who survived an MVA and has NO SYMPTOMS but shows a retroperitoneal hematoma on CT?

Answer 17

Pancreas.

Question 18

What is porcelain gall bladder?

Answer 18

Calcifications of unknown etiology in the gall bladder wall seen on X-Ray. Cholocystectomy is recommended as 11 to 33% progress to cancer.

Question 19

Which drugs can cause pill induced esophagitis?

Answer 19

Tetracycline, KCl and bisphosphates

Question 20

In an alcoholic what causes encephalopathy after an episode of hematemesis?

Answer 20

An increase protein load from the gut causes excess ammonia in the blood that the liver cannot metabolize. (OJO: Ammonia is not equal to BUN)

Question 21

What is the most common location for tears in the rectum?

Answer 21

Posterior midline distal to the dentate line.

Question 22

Why should aspirins be avoided in children? (Except in Kawasaki’s) What are the symptoms?

Answer 22

Reye’s syndrome = Hepatoencephalopathy. Seen after using aspirin to treat viral infections. Causes: Hypoglycemia, hepatomegaly, fatty liver, coma, mitochondrial abnormalities.

Question 23

What is a VIPoma and what are its symptoms? What is the treatment?

Answer 23

Pancreatic tumor that secretes Vasoactive Inhibitory Peptide (VIP) which causes WDHA syndrome.
WD = Watery secretory Diarrhea
H = Hypokalemia
A = Achlrohydria (low HCl)
Relieved by inhibition with Somatostatin.

Question 24

Describe the his logic appearance of carcinoid tumors.

Answer 24

Nests or sheets of uniform cells with eosinophilic cytoplasm and round nuclei. Derived from enterochromaffin cells.

Question 25

Which enzyme is the target of fibrates?

Answer 25

7alpha-hydroxylase is unregulated by vibrates and thus cholesterol is degrade. Estrogens have the opposite effect.

Question 26

How can intestinal absorption independent of pancreatic function be tested?

Answer 26

D-xylose is a monosaccharide that does not require amylase to be broken down (like glucose or maltose)

Question 27

Which part of the stomach receives blood from the splenic artery ONLY?

Answer 27

The proximal part of the greater curvature is supplied by the short gastric arteries from the splenic artery. Another section of the stomach is supplied by the left gastroepiploic artery from the splenic artery but this anastemoses with the right gastroepiploic artery coming from the gastroduodenal artery.

Question 28

Which type of colonic polyp is more likely to be malignant?

Answer 28

Adenomatous > Hyperplastic = Hamartomatous = Inflammatory = Lymphoid

Villous > Tubular

Question 29

Which type of antibodies are specific for primary biliary cirrhosis?

Answer 29

Antimitochondrial

Question 30

What is acute a calculous cholecystitis?

Answer 30

It is an infection of the gallbladder without any stones seen in very ill or hospitalized patient.

Question 31

What causes gynecomastia in liver cirrhosis? What else does this same mechanism cause?

Answer 31

It is caused by a decreased estrogen metabolism in combination with higher albumin testosterone binding. This also causes spider angiomata, testicular atrophy and decreased body hair.

Question 32

What does a deficiency in fatty acid beta oxidation cause?

Answer 32

Beta oxidation inside the mitochondria is require for the synthesis of ketone bodies by the creation of Acteyl-CoA from Acyl-CoA. This deficiency can be caused by carnitine wasting.

Question 33

What is the clinical presentation of gallstone ileum?

Answer 33

The large stone creates a fistula between the GI and the bile ducts/gallbladder. The stone then gets stuck at eh ileocecal valve and the patient presents with distention, diffuse pain (right>left) and air in the biliary tree.

Question 34

What is seen on liver biopsy of acute HAV hepatitis?

Answer 34

Ballooning degeneration, mononuclear cells, and Councilman bodies (eosinophilic apoptotic hepatocytes)

Question 35

What is the most common benign liver tumor?

Answer 35

Cavernous Hemangioma

Question 36

What is SMA syndrome? What can cause it?

Answer 36

Obstruction of the transverse duodenum caused by decreased angle between the aorta and SMA. Caused by sudden loss of fat, lordosis, or operations.

Question 37

Post-op signs of significant liver failure are indicative of…

Answer 37

Massive centrilobular hepatic necrosis caused by halogenated inhalation anesthetics. (Halotane, Enflurane, Isoflurane, Sevoflurane)

Question 38

The activation of what enzyme can initiate a cascade that leads to acute pancreatitis?

Answer 38

Trypsinogen gets activated to Trypsin. Trypsin activates all the other enzymes that cause damage.

Question 39

What are the two histologic findings in Crohn’s Disease?

Answer 39

Transmural Inflammation & Noncaseating Granulomas.

Question 40

What is the progression of mutations in Colorectal Cancer?

Answer 40

APC
K-RAS
p53 and/or DCC
(AK-53)

Question 41

Which drugs are used to treat motion sickness?

Answer 41

Meclizine and Dimenhydrinate are first generation antihistamines with mild antimuscarinic activity.

Question 42

What is diphenoxylate?

Answer 42

It is a opiod that targets the mu receptor and decreases GI motility. Given at low doses for diarrhea with low dose atropine to cause undesired effects that prevent addiction.