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USMLE Step 2 CK Flash Cards > Gastrointestinal > Flashcards

Flashcards in Gastrointestinal Deck (101)
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1
Q

Most common asked or tested physiological changes as a result of cirrhosis with progressive liver fibrosis

A
  • Formation of a high-resistance system (portal hypertension), results in the following:
  • ⬆Nitrous oxide and vasodilatory factors (from bacterial products [endotoxin] accumulated due ⬇host defenses, ⬆portosystemic shunting➡⬇toxin clearance)
  • Splanchnic vasodilation➡⬇systemic vascular resistance, compensatory ⬆HR, CO▶Hyperdinamic circulation
  • (+) RAAS and ADH➡Na and H2O retention
2
Q

Most specific and sensitive test to evaluate celiac disease

A

IgA anti-tissue transglutaminase (anti-tTG) and anti-endomysial antibodies (anti-EMA)►jejunal mucosal damage

*Serum antigliadin antibody no longer used routinely►lower sensitivity and specificity

3
Q

How do you diagnose celiac disease without small bowel biopsy?

A

Positive serology (anti-tTG, anti-EMA) + confirmed dermatitis herpetiformis by Bx

*Small bowel biopsy is the most accurate test

4
Q

Most accurate test of celiac disease and its common findings

A

Small bowel biopsy→blunting of distal duodenal and/or proximal jejunal villi, crypt hyperplasia, intraepithelial lymphocytosis

*Always necessary to exclude bowel wall lymphoma

5
Q

How do you differentiate corticosteroid-induced vs statin-induced myopathy?

A
  • Corticosteroid induced→muscle enzymes normal, EMG normal. Lower extremity weakness and proximal atrophy. No correlation with dosage or duration.
  • Statin-induced→↑↑ CPK ten times upper limit, weakness
6
Q

Enough findings to diagnose Wilson disease. Most accurate test to Dx.

A
  • Low ceruloplasmin concentration (<20 mg/dL), Keyser-Fleischer rings on slit-lamp examination
  • Liver Biopsy
7
Q

How do you differentiate between Rotor vs Dubin-Johnson syndrome?

A
  • Dubin-Johnson→lack elevation of urinary coproporphyrins, has darkly pigmented liver
  • Rotor→milder in presentation without black liver, ↑urinary coproporphyrins
8
Q

When do you evaluate for liver transplantation?

A
  • Decompensated liver failure
  • Portal hypertension
  • ↓Synthetic function (variceal hemorrhage, ascites, encephalopathy)

*Liver biopsy→evaluate extent of structural damage to the liver and candidacy for liver transplantation

9
Q

Esophagus manometry results in scleroderma. How do you suspect esophageal compromise?

A
  • ↓Lower esophageal sphincter pressure, ↓esophageal peristalsis
  • Gastroesophageal reflux disease (GERD) and dysphagia
10
Q

What is motility-type dysphagia? Example of disease with that.

A
  • Difficulty with liquids and solids from the onset of symptoms
  • Diffuse esophageal spasm
11
Q

Test to confirm lactose intolerance

A

Lactose hydrogen breath test➡⬆hydrogen levels after lactose ingestion (bacterial carbohydrate metabolism)

12
Q

Gradual luminal narrowing of the esophagus after many years of gastroesophageal reflux disease (GERD).

A

Peptic esophageal stricture

13
Q

Diagnostic test for gastrointestinal angiodysplasia

A

Mesenteric angiography▶Dilated, slow-flowing vein in the colon

14
Q

Treatment for gastrointestinal angiodysplasia

A

Endoscopic ablation→cauterization or laser coagulation (if fails, surgical removal of affected bowel)

15
Q

Most common cause of lower GI bleeding

A
  1. Diverticulosis

2. Angiodysplasia

16
Q

How do you screen for factitious diarrhea due to laxative abuse?

A

Stool screen for diphenolic (eg, bisacodyl) or polyethlynele-containing laxatives

17
Q

How do you confirm the diagnosis of factitious diarrhea due to laxative abuse?

A

Colonoscopy➡Melanosis colia▶dark brown discoloration of the colon with pale patches of lymph follicles (alligator skin)

18
Q

Useful tests to rule out factitious diarrhea

A
  • Stool osmolality: Normal➡290 mOsm/Kg (plasma). Hypoosmolality➡addition of water or other dilute fluid. Hyperosmolality➡addition of concentrated fluid )urine)
  • Stool electrolytes: ⬆Mg and PO4▶overuse of saline osmotic laxatives
  • Stool osmotic gap: Osmotic laxatives (lactulose, polyethyleneglycol)▶⬆osmotic gap diarrhea. Senna and bisacodyl▶⬇osmotic gap secretory diarrhea
19
Q

Where is the most common location of the VIPoma? How do you confirm the diagnosis?

A
  • Pancreatic tail

- VIP level >75 pg/mL

20
Q

Most common electrolytic disturbances in VIPoma syndrome

A
  • VIPoma syndrome (pancreatic cholera)►secretory, watery diarrhea and ↓ gastric acid secretion→hypokalemia and hypo or achlorhydria
21
Q

Colonoscopy recommendations for colon cancer screening in inflammatory bowel disease

A
  • 8-10 years after diagnosis (12-15 years if only left colon)
  • Repeat every 1-3 years
22
Q

Colonoscopy recommendation for colon cancer screening in lynch syndrome (HNPCC)

A
  • Age 20-25 years

- Repeat every 1-2 years

23
Q

Colonoscopy recommendations for colon cancer screening in classic familial adenomatous polyposis

A
  • Age 10-12 years

- Repeat anually

24
Q

Colonoscopy recommendations for colon cancer screening family history of adenomatous polyps or CRC

A
  • Age 40 or 10 years before the age of diagnosis of the relative
  • Repeat every 5 years
25
Q

What is the long-term outcome of nonalcoholic fatty liver disease (NAFLD)?

A
  • Hepatic Fibrosis 40%

- Cirrhosis 10-15%

26
Q

Since hepatic steatosis is similar between NAFLD and alcoholic liver diseases, how can you differentiate both?

A
  • NAFLD→AST/ALT ratio <1
  • Alcoholic liver disease→AST/ALT ratio 2:1

*Off course ask for severe alcohol exposition

27
Q

Best diagnostic test for esophageal perforation and expected finding

A

Esophagography or CT scan with water-soluble contrast (no barium, it is inflammatory)→Leak from perforation

28
Q

Most probable diagnosis in a patient with chest/back pain, fever, vomiting and pleural effusion. Most common etiologies.

A

Esophageal perforation or rupture

  • Effort rupture (ex, self-induced vomiting, Boerhaave syndrome)
  • Instrumentation (ex, endoscopy), trauma
  • Esophagitis (infection, pills, caustic)
29
Q

Best diagnostic test for esophageal perforation and expected finding

A

Esophagography or CT scan with water-soluble contrast (no barium, it is inflammatory)→Leak from perforation

30
Q

What you should rule out when you find liver decompensation (new-onset ascites, variceal bleeding) in a patient with alcohol-induced cirrhosis?

A

Thrombus or Hepatocellular carcinoma (HCC)➡clot or mass blocking portal or hepatic veins▶Abdominal ultrasound

*Patient with cirrhosis screening with abdominal ultrasound each 6 mo to evaluate new onset asymptomatic HCC

31
Q

Clinical presentation of acute diverticulitis

A
  • Left lower quadrant pain
  • Nausea, vomiting
  • Bladder symptoms (urgency, dysuria, frequency) or sterile pyuria (➕leukocyte esterase, ➖nitrites/bacterias)➡bladder irritation from bowel inflammation
  • Changes bowel habits (diarrhea, constipation)
32
Q

Primary prophylaxis to prevent bleeding from esophageal varicose veins

A
  • Endoscopic variceal ligation (EVL)➡preferred for larger varicose veins
  • Nonselective beta-blocker➡propranolol, nadolol
33
Q

Best initial test and most accurate test for bloody diarrhea

A
  • Best initial➡Stool lactoferrin

- Most accurate➡Stool culture

34
Q

Best initial test and most accurate test for achalasia

A
  • Best initial: Barium esophagram➡”Bird’s beak sign”
  • Most accurate: Manometry➡Failure lower esophageal sphincter to relax (⬇Esophageal peristalsis, ⬆Lower esophageal sphincter tone)
35
Q

Treatments options for achalasia

A
  1. Pneumatic dilation (perforation risk <3%)
  2. Myotomy (more effective but more dangerous)
  3. Botulinum toxin (effect wear off in 3-6 mo, reinjections)
36
Q

Clinical presentation of esophageal spasm. Which are the two forms of them?

A
  • Sudden onset of severe chest pain not related to exertion, can be precipitated by drinking cold liquids
  • Diffuse esophageal spasm (DES) and Nutcracker esophagus

*Both forms clinically indistinguishable. Hard to differentiate at the beginning with coronary disease. EKG and stress test normal

37
Q

Most accurate test for Diffuse esophageal spasm (DES) and Nutcracker esophagus

A

Manometry➡Different pattern of abnormal contraction

38
Q

Treatment for esophageal spastic disorders

A

Calcium channel blockers and nitrates (similar Prinzmetal angina)

*PPIs can improve some cases

39
Q

Important history clue and best initial test for eosinophilic esophagitis

A
  • Asthma and allergic diseases

- Endoscopy➡Multiple concentric rings

40
Q

Most accurate test for eosinophilic esophagitis

A

Biopsy➡Eosinophilic infiltration of esophageal mucosa

41
Q

Best initial and most effective therapy for eosinophilic esophagitis

A
  • PPIs and eliminate allergenic food

- Swallow steroid inhalers (topical effect of steroids)

42
Q

Difference between Schatzki ring and Plummer-Vinson syndrome esophageal lesions

A
  • Schatzki ring➡from acid reflux, associated with hiatal hernia. Scarring or tightening (also called peptic stricture) of the distal esophagus.
  • Plummer-Vinson syndrome➡associated with iron deficiency anemia, rarely transforms into squamous cell cancer. More proximal.
43
Q

Treatment of Schatzki ring and Plummer-Vinson syndrome esophageal lesions

A
  • Schatzki ring➡pneumatic dilation in an endoscopic procedure
  • Plummer-Vinson syndrome➡ iron replacement at first▶may lead to resolution of the lesion
44
Q

Best diagnostic test for Zenker diverticulum

A

Barium studies

*Do not answer nasogastric tube placement or upper endoscopy➡dangerous, may cause perforation

45
Q

Finding on the most accurate test for the scleroderma esophagus compromised

A

Manometry➡inability to close the lower esophageal sphincter▶⬇LES pressure

46
Q

Most common cause of epigastric pain

A

Non-ulcer dyspepsia

47
Q

Treatment for cannabinoid hyperemesis syndrome

A
  • Hot shower or bath

- Antiemetics (ondansetron) or benzodiazepines (lorazepam)

48
Q

Most common cause of peptic ulcer disease

A
  1. Helicobacter pylori

2. NSAIDs

49
Q

Treatment for GERD for whose do not respond to the medical management

A
  • Nissen fundoplication➡wrapping the stomach around the lower esophageal sphincter
  • Endocinch➡suture around the LES
  • Local heat or radiation of LES➡scarring

*About 5% of GERD patients do not respond to medical therapies

50
Q

Indication for stress ulcer prophylaxis

A
  • Mechanical ventilation
  • Burns
  • Head trauma
  • Sepsis with coagulopathy
51
Q

Most common cause of upper GI bleeding

A

Peptic ulcer disease

52
Q

Clinical presentation of gastritis

A
  • Bleeding without pain➡“coffee-ground” emesis, large hematemesis, melena, Heme (guaiac) positive stool
  • Severe, erosive gastritis➡epigastric pain
  • Nausea, vomiting
  • Asymptomatic
53
Q

What you must always rule out in a patient with a gastric ulcer?

A

Gastric cancer is present in 4% of those with GU but in none of those with DU

54
Q

Best next step when you suspect persistent helicobacter pylori infection with a duodenal ulcer and gastric ulcer

A
  • DU: Think antibiotic resistance➡urea breath testing, stool antigen detection, or a repeat endoscopy for biopsy➡if ➕➡switching to metronidazole + tetracycline + PPIs + bismuth
  • GU: repeat endoscopy to exclude cancer
55
Q

What is Non-ulcer dyspepsia?

A

Epigastric pain with a normal endoscopy

56
Q

Clues on clinical presentation that makes you suspect gastrinoma

A

Peptic ulcer disease symptoms + diarrhea (acid inactivates lipase)

57
Q

How are the ulcers from gastrinoma?

A
  • Large (>1–2 cm)
  • Recurrent after Helicobacter eradication
  • Distal in the duodenum
  • Multiple
58
Q

How do you confirm gastrinoma (Zollinger-Ellison syndrome)?

A

Any of them:

  • ⬆Gastrin off antisecretory therapy (PPIs or H2 blockers) with high gastric acidity
  • ⬆Gastrin despite a high gastric acid output
  • Persistent ⬆Gastrin despite injecting secretin
59
Q

What is the most accurate test to identify metastases from gastrinoma?

A

Somatostatin receptor scintigraphy (nuclear octreotide scan) + endoscopic ultrasound
(Always do first CT and MRI)

*Gastrinoma is associated with a massive increase in the number of somatostatin receptors in the abdomen

60
Q

Best initial treatment for diabetic gastroparesis

A

Dietary modifications➡Blenderize foods, Restore fluids, Correct potassium and glucose levels

*Not always have to confirm diagnose to start treatment

61
Q

Most accurate test to confirm diabetic gastroparesis

A

Nuclear gastric emptying study➡Bolus of food tagged with technetium▶delay in the emptying of food

62
Q

Best initial test for diabetic gastroparesis

A

Upper endoscopy or abdominal CT scan➡ excludes luminal gastric mass or abdominal mass compressing the stomach

63
Q

Which treatments can you give if the best initial therapy for diabetic gastroparesis fails?

A
  1. Metoclopramide➡⬆gastrointestinal motility (Do not use permanently: Dystonia and hyperprolactinemia)
  2. Erythromycin + antiemetics➡⬆gastrointestinal motility
  3. Gastric electrical stimulation (gastric pacemaker)
64
Q

Most common cause of lower GI bleeding

A

Diverticulosis

65
Q

What is the most important next step in the management of GI bleeding?

A

Fluid replacement with high volumes (normal saline or Ringer lactate)

66
Q

Initial medical treatment for esophageal and gastric varices

A

Octreotide (somatostatin)➡⬇portal pressure

67
Q

Best initial therapy for clostridium difficile colitis. Next best step if there is NO RESPONSE and if there is RECURRENCE.

A
  • Oral Vancomycin
  • NO RESPONSE➡Fidaxomicin
  • RECURRENCE (there was resolution)➡tapered dose of vancomycin (another course) or fidaxomicin
68
Q

What is fulminant clostridium difficile infection? Treatment.

A
  • ⬆WBC, Metabolic acidosis, ⬆lactate, ⬆creatinine

- Vancomycin and metronidazole

69
Q

Most accurate test for chronic pancreatitis

A

Secretin stimulation testing

70
Q

Sensible and specific finding on imaging in chronic pancreatitis

A
  • Abdominal x-ray➡calcification of the pancreas

- Abdominal CT scan➡pancreatic calcification (80% to 90% sensitive)

71
Q

Most sensitive predictor of anastomotic leak after bariatric surgery (Roux-en-Y gastric bypass). What other manifestations you may find?

A
  • HR>120/min most sensitive predictor

- Fever, abdominal pain, tachypnea

72
Q

Why do patients with fat malabsorption (Ex, Chron disease, small intestinal disease) have a high risk of nephrolithiasis?

A

Hyperoxaluria

  • Normally Calcium binds Oxalate in gut➡❌Oxalate absorption
  • Fat malabsorption➡Calcium is bound by fat➡Oxalate is absorbed; ❌absorb bile salts➡⬇bile salts reabsorption in small intestine➡⬆⬆bile salts damage colonic mucosa➡⬆Oxalate absorption
73
Q

Serologic testing to differentiate Crohn disease from Ulcerative colitis

A
  • CD➡ANCA➖, Anti-Saccharomyces cerevisiae antibody (ASCA)➕

- UC➡ANCA➕, ASCA➖

74
Q

Which procedure you must avoid in a patient with diverticulitis and why?

A

Colonoscopy➡infection weakens the colonic wall➡risk of perforation

75
Q

Best test for diverticulitis

A

CT scan

76
Q

Worst prognosis marker in acute pancreatitis

A

Low calcium

77
Q

When you must rule out infection in pancreatitis? How do you do it?

A
  • Severe necrosis➡>30% necrosis on CT or MRI

- Needle biopsy➡only way to confirm infection

78
Q

Best initial and confirmatory test for spontaneous bacterial peritonitis

A

Ascitic fluid study➡Total leukocyte>1000, Neutrophils >250▶confirm diagnosis

*Culture is variable positive and gram stain has low sensitivity

79
Q

Which symptom is very important to ask for when suspect hepatopulmonary syndrome?

A

Orthodeoxia➡hypoxia upon sitting upright

80
Q

Most accurate blood test for primary biliary cholangitis

A

Antimitochondrial antibody

81
Q

From the patient history, how you may distinguish primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC)?

A

80% of PSC occurs in association with IBD

82
Q

Which test may help you distinguish PBC and PSC?

A
  • PBC➡antimitochondrial antibody and liver biopsy (most accurate)
  • PSC➡MRCP or ERCP▶beading, narrowing, strictures in biliary system (most accurate). Bx is not essential for Dx. (ONLY cause of cirrhosis for which Bx is the not most the accurate)
83
Q

Findings in the iron studies profile on hemochromatosis

A

⬆serum Iron, ⬆Ferritin, ⬇Iron binding capacity

*Best initial test for hemochromatosis

84
Q

Besides the liver biopsy, which studies are enough to confirm hemochromatosis?

A

MRI➡⬆iron deposition in the liver

Hemochromatosis gene (HFE; mutation C282y) testing

85
Q

Hemochromatosis treatment

A

Phlebotomy

86
Q

How is the clinical presentation of Wilson disease in other organs than the liver compromise?

A
  • CNS➡Psychosis, tremor, dysarthria, ataxia, seizures
  • RBCs➡Coombs negative hemolytic anemia
  • Kidneys➡Renal tubular acidosis, nephrolithiasis
87
Q

Best initial test and most accurate test for Wilson disease

A
  • Best initial➡Slit-lamp examination▶Kayser-Fleischer rings
  • Most accurate➡abnormally ⬆copper excretion into urine after giving penicillamine
  • ⬇Ceruplasmin is NOT the most accurate
  • Liver Bx is sensitive and specific
88
Q

Key findings on imaging and serum when suspect autoimmune pancreatitis

A
  • CT scan➡enlarged, “sausage-shaped” pancreas
  • ⬆serum IgG4 (IgG4-related pancreatitis), ➕ANA and rheumatoid factor

*Associated with Sjögren syndrome, autoimmune thyroiditis, interstitial nephritis, sclerosing cholangitis

89
Q

Treatment options for Wilson disease

A
  • Penicillamine➡chelate copper, removes it from body
  • Zinc➡❌intestinal copper absorption
  • Trientine➡copper-chelating

*Penicillamine cannot be used with allergy to penicillin➡zinc or trientine.

90
Q

How do you assess for severe exocrine pancreas insufficiency? For which diagnosis is it useful?

A
  • ⬇Fecal elastase
  • ⬇serum Trypsinogen
  • Chronic pancreatitis
91
Q

Which findings on feces you may find high on inflammatory bowel disease?

A

⬆️Calprotectin or Lactoferrin

⬆️Fecal leukocytes

92
Q

In a patient with liver disease, what is the indication to receive prophylaxis for SBP?

A

Cirrhosis with ascites + variceal bleeding

93
Q

Classic clinical presentation of pellagra and its cause

A
  • Niacin deficiency
  • Clinical presentation, “3 Ds”:
  • Dermatitis - sun-exposed areas, rough, hyperpigmented, scaly
  • Diarrhea - watery, loss appetite, nausea, abd pain
  • Dementia - memory loss, affective symptoms (depression), psychosis
94
Q

Why you may have niacin deficiency? Which is the disease?

A

Pellagra

  • Diet based on corn products (developing countries)
  • Impaired nutritional intake (developed countries; alcoholics, chronic illness)
  • Carcinoid syndrome➡⬇tryptophan
  • Hartnup disease➡❌tryptophan absorption
  • Prolonged Isoniazid therapy➡❌tryptophan metabolism
95
Q

Most appropriate initial step and mainstay of treatment in a patient with MALT

A

Antibiotic eradication of Helicobacter pylori

*Majority of patients have complete recovery after Tx

96
Q

Common trigger of GI bleeding in a patient with angiodysplasia

A

Aortic stenosis➡destruction of vWF multimers when pass through damage valve

97
Q

What may suggest nocturnal diarrhea?

A

Secretory diarrhea

*Chronic infection, microscopic colitis, bile salt diarrhea, hormone-secreting tumor (gastrinoma, VIPoma)

98
Q

Most common inciting factors of hepatorenal syndrome

A
  • Spontaneous bacterial peritonitis

- Gastrointestinal bleeding

99
Q

Characteristic rectal findings on colonoscopy of chronic radiation proctitis

A
  • Multiple telangiectasiaa
  • Mucosal pallor and friability

*Submucosal fibrosis and obliterative endarteritis➡tissue hypoxia▶neovascularization➡telangiectasias➡significant hematochezia

100
Q

Imaging findings of hydatid cyst

A

Eggshell calcification of a hepatic cyst (CT scan)

*Echinococcus granulosus➡unilocular cystic lesions in any organ (liver, lung, bone, muscle); Echinococcus multilocularis➡multiple lesions

101
Q

A 57-year-old man with colonoscopy 5 years ago showed a tubular adenoma, with the rest of the cardiovascular risk factors under control. Most appropriate next step.

A

Colonoscopy

  • Low-risk polyps: 1 or 2 small tubular adenomas➡screening every 5 to 10 years
  • Multiple polyps: >3, atypical features or large, serrated polyps➡screening every 3 years