5. Gastrointestinal

Question 1

Patients with IBD are at higher risk of developing what complication?

Answer 1

Toxic megacolon (total or segmental nonobstructive colonic dilation, severe bloody diarrhea, fever, tachy)
Other causes of toxic megacolon: ischemic colitis, volvulus, diverticulitis, infx (C diff)
Tx- IVF, broad-spectrum abx, bowel rest, IV corticosteroids

Question 2

Middle-aged woman with fatigue, pruritus, hepatomegaly, and elevated alkaline phosphatase. Diagnosis? How can you confirm it?

Answer 2

Primary biliary cholangitis - intrahepatic cholestasis d/t autoimmune destruction of small bile ducts
Dx w/ serum anti-mito ab titers
Note: anti-smooth mm abs and ANA is assoc with autoimmune hepatitis.

Question 3

What commonly contributes to prolonged post-op ileus (nausea, abd distension, obstipation, hypoactive bowel sounds)?

Answer 3

Opiates - dec GI motility

Question 4

Hepatomegaly with mild elevations in liver tests in the absence of causes of secondary hepatic fat accumulation.

Answer 4

Nonalcoholic fatty liver disease

Question 5

In what situation would a patient with celiac disease have absent IgA anti-endomysial and anti-tissue transglutaminase abs?

Answer 5

If there is concurrent selective IgA deficiency

Otherwise, IgA anti-endomysial and anti-tissue transglutaminase abs are highly predictive of celiac disease

Question 6

What is required to make a diagnosis of acute liver failure?

Answer 6

Severe acute liver injury (ALT & AST >1000)
Hepatic encephalopathy (confusion, asterixis)
Synthetic liver dysfunction (INR >=1.5)

Question 7

What is a common complication of vascular surgery, esp in older patients with extensive underlying atherosclerosis? Note: CT shows thickening of bowel wall and colonoscopy shows cyanotic mucosa and hemorrhagic ulcerations

Answer 7

Ischemic colitis.
Repair of a AAA is a common precipitating event as well. Prolonged aortic clamping and impaired blood flow through the IMA.

Question 8

What presents with constant and gnawing epigastric pain that’s worse at night?

Answer 8

Pancreatic cancer - also presents with anorexia/wt loss, and jaundice d/t extraheaptic biliary obstruction
Note: peptic duodenal ulcer has periodic epigastric pain relieved by meals

Question 9

What can cause hypogonadism (testicular atrophy, ED), and decreased thyroid hormones?

Answer 9

Cirrhosis causes hypogonadism by primary gonadal injury or hypothalamic-pituitary dysfunction. Elevated estradiol also seen –> telangiectasias, palmar erythema, testicular atrophy, gynecomastia
Dec synth of serum binding proteins –> dec synthesis of total T3 and T4

Question 10

Severe retrosternal pain, dyspnea, subcutaneous emphysema (suprasternal crepitus), odynophagia, and signs of sepsis in patient with history of alcoholism and prolonged vomiting?

Answer 10

Spontaneous perforation of the esophagus - assoc w/Boerhaave synd
Will see pneumomediastinum

Question 11

When should you screen for colon cancer (ie perform colonoscopy) in the following:

1. Fhx of FAP or colorectal cancer
2. IBD (UC, Crohns)
3. FAP
4. HNPCC (lynch)

Answer 11

1. 40yo or 10y bf age of dx in relative. Repeat every 3-5y
2. Begin 8 y post dx (12-15y if only in L colon). Colonoscopy w/bx every 1-2 y
3. Begin at age 10-12. Colonoscopy every year
4. Begin at age 20-25. Colonoscopy every 1-2y.

Question 12

Differentiate biliary colic due to gallstones from acute cholecystitis and acute pancreatitis

Answer 12

Biliary colic - exacerbated by fatty meals, lasts <6h, resolves completely bw episodes. No fever, abd tenderness on palp or leukocytosis
Acute cholecystitis - similar to biliary colic but lasts >5h, have fever, leukocytosis and tenderness to palp (pos murphy’s sign)
Acute pancreatitis - constant epigastric pain radiating to back. Doesnt resolve spont

Question 13

How do you definitively diagnose esophageal sx in young patient vs patient >55?

Answer 13

Young - barium esophagram

>55 - endoscopy with biopsy (suspect esophageal cancer).

Question 14

Esophageal rupture can be due to endoscopy, severe retching, or penetrating trauma. Sx = acute chest pain, subcutaneous emphysema, L pleural effusion. How can you confirm the dx?

Answer 14

Contrast esophagram - water-soluble contrast is preferred bc less inflam to tissues.

Question 15

Gastric outlet obstruction can be caused by many disease processes and is characterized by early satiety, nausea, nonbilious vomiting, and weight loss. In a patient with history of acid ingestion, what is the most likely cause?

Answer 15

Pyloric stricture.
Abdominal succussion splash may be heard - stethoscope over upper abdomen and rocking patient back and forth at hips –> splash sound = hollow viscus filled with fluid and gas

Question 16

What GI abnormality is assoc with Down syndrome?

Answer 16

Duodenal atresia/stenosis. Presents with bilious vomiting in first 2 days of life. Abd NOT distended bc gas cant pass the duodenum. Trapped air in stomach and first part of duodenum (double bubble sign).
Note: VSD and ASD are common cardiac findings with Down synd

Question 17

Presence of a triple bubble sign and gasless colon in an infant with bilious vomiting and adominal distension indicates what?

Answer 17

Jejunal atresia - thought to be due to a vascular accident in utero –> necrosis and reaborption of fetal intestine
RF: prenatal cocaine exposure, vasoconstrictive drugs

Question 18

How can you differentiate the etiology of conjugated hyperbilirubinemia via liver enzymes?

Answer 18

Inherited: normal transaminases and alk phos
Intrinsic liver disease (viral hep): predominately elevated transaminases and normal alk phos
intrahepatic cholestasis or biliary obstruction: elevated alk phos out of proportion to transaminases

Question 19

What should be suspected in a well-appearing neonate that has painless blood stools?

Answer 19

Milk or soy protein proctocolitis. Eliminate maternal dairy and soy products or switch to hydrolyzed formula.
non-IgE mediated immune response to proteins in formula or breast milk that causes rectal and colonic inflammation

Question 20

Young adult w/hx of abd surgery in last 6 mo with nausea, vomiting, abdominal bloating, and dilated loops of bowel on abd x-ray most likely has what?

Answer 20

complete small bowel obstruction. Post-op adhesions are MCC

Question 21

Differentiate origin and presentation of hisrschsprung disease and meconium ileus

Answer 21

Hirsch - Down synd; rectosigmoid, normal meconium consistency, positive squirt sign
Meconium ileus: CF; ileum obstruction, inspissated consistency, neg squirt sign.

Question 22

How do you manage biliary cysts?

Answer 22

Surgical excision to reduce risk of cholangiocarcinoma.

Sx: abd pain, jaundice, palpable mass.

Question 23

In evaluating ascities, a SAAG >= 1.1 indicates what? SAAG < 1.1 indicates what?

Answer 23

> =1.1 indicates portal hypertensive etiologies (eg cardiac ascites, cirrhosis)
<1.1 indicates non-portal hypertensive etiologies (eg malignancy, pancreatitis, nephrotic syndrome, Tb)

Question 24

Why are asian babies predisposed to physiologic jaundice of the newborn?

Answer 24

Asian newborns have UGT activity –> can clear bilirubin

Question 25

Newborns of moms with what blood group are at risk for immune hemolytic anemia and severe hyperbilirubinemia?

Answer 25

ABO and Rh incompatibility: O-neg or Rh-neg

Question 26

When do you consider the following in management of GERD? 1. Upper GI endoscopy 2. Empiric trial of PPIs 3. pH monitoring

Answer 26

1. alarm sx: dysphagia, odynophagia, wt loss, anemia, GI bleeding, recurrent vomiting 2. No alarm sx 3. chronic sx

Question 27

What condition is common in elderly men (>60) and presents as dysphagia, regurgitation, foul-smelling breath, aspiration, and occasionally palpable mass? Dx and tx?

Answer 27

Zenker's diverticulum | Contrast esophagogram is the best test to confirm. Tx surgically

Question 28

What type of polyps are considered neoplastic, and what subtype has greater risk of malignant transformation?

Answer 28

Adenomatous - villous higher risk | Note: hyperplastic, hamartomatous, inflammatory, and submucosal polyps have low malignant potential

Question 29

What biliary condition is characterized by fatigue, pruritus, and may be assoc with ulcerative colitis. Lab tests show elevated alk phos and smaller inc in liver enzymes

Answer 29

Primary sclerosing cholangitis | Note: bacterial cholangitis is assoc with Charcot triad (jaundice, RUQ pain, fever)

Question 30

What complication is commonly seen in peds patients after blunt abdominal trauma and present with epigastric pain, vomiting 24-36h after initial injury? Management

Answer 30

``` Duodenal hematoma (thinner abd wall muscles, less abd fat, more pliable ribs than adults). Tx - gastric decompression and parental nutrition ```

Question 31

Chronic dysphagia to solids and liquids, regurgitation, heartburn and manometry showing inc LES resting pressure is a sign of what? What does barium esophagram show?

Answer 31

Achalasia (incomplete LES relaxation and dec peristalsis of distal esophagus) Bird beak

Question 32

What is the main diagnostic criteria for spontaneous bacterial peritonitis?

Answer 32

Positive ascities fluid culture and neutrophil count of >=250/mm3

Question 33

Treatment of actively bleeding esophageal varices involves hemodynamic support, endoscopic therapy, prophy abx, and what pharm tx?

Answer 33

Somatostatin anaalgoues (eg octreotide) - inhibit release of vasodilator hormones --> indirect spanchnic vasoconstriction --> dec portal flow

Question 34

Patients at average risk of developing colon cancer should begin screening at what age? If there is an affected first-degree relative, when should screening occur?

Answer 34

1. 50yo first colonoscopy, then q10 years or + FOBT annual, or sigmoidoscopy q5y + FOBT q3 year 2. Age 40 or 10 years bf age of relative dx (whichever is first)

Question 35

In patients with primary biliary cholangitis (pos antimito ab), there is destruction of intrahepatic bile ducts --> bile stasis and cirrhosis. It can be assoc with severe hyperlipidemia which can cause xanthelasmas. What other complications is it assoc with?

Answer 35

Osteomalcia, osteoporosis Malabsorption hepatocellular carcinoma

Question 36

In a patient with chronic liver disease, you much treat the underlying cause and prevent further liver damage. How can you prevent further damage?

Answer 36

Avoid alcohol | Hep A and hep B vaccination

Question 37

How are preceding viral infx (eg gastroenteritis) thought to play a role in serving as a lead point for intussuception in kids? Is pain constant or periodic?

Answer 37

Inflammation of intestinal lymphatic tissue (eg Peyers patches) serve as a lead point. Most kids dont have an identifiable lead point. Periodic pain. Currant jelly stools

Question 38

A positive urine bilirubin assay indicates what?

Answer 38

Buildup of conjugated bilirubin Conj bili is usually degraded in the intestines, but when there is hepatic dysfunction, biliary obstruction, or a defect in hepatic bili secretion, there is a plasma buildup of conj bili which leaks into urine. Note: hemolysis would lead to unconj hyperbili (highly insoluble and not seen in urine) and positive urobilinogen assay

Question 39

How do you manage uncomplicated small bowel obstruction? How does this vary from uncomplicated SBO?

Answer 39

Initial: conservative (bowel rest, NG tube suction, correct metabolic derrangements) If SBO is complicated - emergency abd exploration necessary.

Question 40

Infant with inspiratory stridor exacerbated by exertion or stress with sx appearing in first few weeks of life should be suspected of having what?

Answer 40

Laryngomalacia. | Note: unlike choanal atresia, cyanosis is uncommon.

Question 41

How can a recent MI result in acute mesenteric ischemia?

Answer 41

Abrupt arterial occlusion (mesenteric artery) from cardiac embolic events (eg ventricular thromboembolism). Labs show leukocytosis, inc Hb, inc amylase, and metabolic acidosis

Question 42

How do the following substances contribute to mucosal injury? 1. aspirin 2. cocaine 3. aspirin + ETOH

Answer 42

1. Aspirin: dec protective prostaglandin protection 2. Cocaine: vasoconstriction--> dec gastric blood flow 3. Aspirin +ETOH: direct mucosal injury This can result in hematemesis and abd pain

Question 43

How can the liver be affected in the setting of hypotension?

Answer 43

Ischemic hepatic injury can occur - see massive inc in AST and ALT with milder inc in total bili and alk phos. Note: acute HAV or HBV have large inc in AST and ALT, but also have signif hyperbili

Question 44

How can prolonged isoniazid therapy result in pellagra?

Answer 44

Isoniazid can interfere with niacin metabolims --> niacin def --> pellagra (dermatitis, diarrhea, dementia)

Question 45

Patient with chronic, intermittent epigastric pain and postprandial discomfort is typical of what? Common causes? RF?

Answer 45

Dyspepsia/peptic ulcer disease Causes: NSAIDs, H pylori, GERD RF: low-income country with high prevalence of infx (Eg india) can place a pt at risk of H pylori (urease-producing bacteria) infx.

Question 46

What intervention has the greatest impact on decreasing a patient's risk fo pancreatic cancer?

Answer 46

Stop smoking Other factors such as obesity, nonhereditary chronic pancreatitis can inc risk slightly. Germline mutations (eg BRCA1, BRCA2, Peutz-Jeghers syndrome) also inc risk

Question 47

What liver disease resembles alcohol-induced liver disease but occurs in patients with minimal or no ETOH history and is assoc with insulin resistance?

Answer 47

Nonalcoholic fatty liver disease. | Insulin resistance --> inc lipolysis, triglycerides and hepatic uptake of FA.