Usmle Step 1 Dit: Gastrointestinal

Front 1

Primary absorption cells of intestine

Back 1

Villi

Front 2

Simple columnar epithelial cells that have digestive enzymes

Back 2

Villi

Front 3

Where are crypts of leiberkuhn located?

Back 3

Jejunum, duodenum

Front 4

Where are villi and microvilli located?

Back 4

Mostly duodenum

Front 5

What hormone is responsible for increased water and electrolyte secretion, increased relaxation of intestinal smooth muscle and sphincters

Back 5

Vasoactive intestinal polypeptide

Front 6

Copious watery diarrhea, hypokalemia and achlorhydria

Back 6

Vasoactive intestinal polypeptide

Front 7

Glands that secrete alkaline mucus. Located in duodenal submucosa. Seen in peptic ulcer disease when they hypertrophy.

Back 7

Brunner glands

Front 8

How is trysinogen converted to trysin?

Back 8

Autoactivation, enterokinase/enteropeptidase

Front 9

Functions of trypsinogen

Back 9

Degrades peptide bonds of arginine or lysine and activates other proteolytic enzymes.

Front 10

True or false:

Di and tripeptides are aborbed faster than single AA

Back 10

True

Front 11

What carbohydrates are absorbed by enterocytes?

Back 11

Glucose, galactose, fructose

Front 12

What is glucose and galactose taken up by?

Back 12

SGLTI (Na+ dependent)

Front 13

What is fructose taken up by?

Back 13

Facilitated diffusion by GLUT-5

Front 14

How are carbohydrates transported to the blood?

Back 14

By GLUT-2

Front 15

Complex carbohydrates ---?--->discaccharides --?-->monosaccharides

Back 15

1. Pancreatic amylase

2. Intestinal brush border enzyme

Front 16

How is fat digested?

Back 16

1. Starts in the mouth with salivary lipase

2. Pancreatic lipase hydrolyzes triacylglycerol into fatty acids, 2-monoacylglycerol

3. Bile salts: emulsify fats and form micelles

4. Micelles get broken down into triacylgylcerol and cholesterol and are packaged into chylomicrons

Front 17

Antiacids are a commen cause of _______ deficiency.

Back 17

Iron

Front 18

Quinolone and tetracyclines are a common cause of _______ deficiency.

Back 18

Iron

Front 19

Cereals and fibers are a common cause of _________ deficiency.

Back 19

Iron

Front 20

Poor nutrition is a common cause of ______Deficiency.

Back 20

Folate

Front 21

Alcoholism is a common cause of ______deficiency

Back 21

Folate

Front 22

Goats milk is a common cause of ________deficiency.

Back 22

Folate

Front 23

Malnutrition is a common cause of _______ deficiency.

Back 23

Vit B12

Front 24

Decreased absorption is a common cause of _________ deficiency.

Back 24

Vit B12

Front 25

Eggs and milk are common causes of ______ deficiency.

Back 25

Iron

Front 26

Gastric bypass is a common cause of _________ deficiency

Back 26

Iron

Front 27

What does vit B12 deficiency cause?

Back 27

Megaloblastic anemia

Front 28

What is needed in order for vit B12 to be absorbed in parietal cells?

Back 28

Intrinsic factor

Front 29

What is schillings test?

Back 29

Radiolabeled cyanocobalamin given orally to determine if it was absorbed by ileum. Measurment of urinary excretion of labelled B12 in 24h.

Front 30

What is the normal B12 excretion rate for schillings test?

Back 30

>8% of oral dose recovered in urine

Front 31

Malaborption syndrome that affects all of small bowel, responds to antibiotics. Causes vitamin deficiency.

Back 31

Tropical spur

Front 32

Malaborption syndrome caused by tropheryma whipplei

Back 32

Whipple disease

Front 33

PAS + foamy macrophages with cardiac symptoms, arthalgias, neurologic symptoms, weight loss, lymphadenopathy, hyperpigmentation.

Back 33

Whipple disease

Front 34

Autoimmune-mediated intolerance of wheat (gliadin)

Back 34

Celiac spur

Front 35

Malabsorption syndomre associated with HLA-DQ2, HLA-DQ8 and northern american descent.

Back 35

Celiac spur

Front 36

Foul smelling stool, stunted growth, failure to thrive, affects mostly proximal bowel (distal duodenum and proximal jejunum)

Back 36

Celiac spur

Front 37

Malabsorption syndrome that increases risk of malignancy (T cell lyphoma, GI cancer, breast cancer)

Back 37

Celiac spur

Front 38

Most common cause of disaccharide deficiency

Back 38

Lactose intolerance

Front 39

When does the lactose tolerance test +?

Back 39

- Symptoms

- Glucose rises <20 mg/dL

Front 40

What does lactose normally break down into?

Back 40

Glucose and galactose

Front 41

When can a self-limited lactose deficiency occur?

Back 41

Viral diarrhea

Front 42

Inability to produce chylomicrons, decreased secretion of cholesterol, VLDL, LDL into bloodstream and fat accumulation in enterocytes

Back 42

Abetalipoproteinemia

Front 43

Failure to thrive, acanthocytosis, ataxia, malabsorption (ADEK), night blindness

Back 43

Abeatlipoproteinemia

Front 44

Malabsorption syndrome due to cystic fibrosis, obstructing cancer, chronic pancreatitis. Malabsorption of vitamin A, D, E, K

Back 44

Pancreatic insufiency

Front 45

What are the main causes of bacterial overgrowth?

Back 45

Stasis, increased pH, impaired immunity, antibiotics (clindamycin, ampicillin), inflammatory infiltrates in bowel wall

Front 46

What can clostridium dificile cause?

Back 46

Pseudomembranous colitis

Front 47

What is the tx for clostridium dificile?

Back 47

Metronidazole, oral vancomycin

Front 48

How is the diagnosis of irritable bowel syndrome made?

Back 48

Recurrent abdominal pain associated with 2 or more of the following:

- pain improves with defecation

- change in stool frequency

- change in stool appearance

Front 49

What are the non-GI manifestations of irritable bowel syndrome?

Back 49

Urinary frequency, urgency, dysmenorrhea, dyspareunia, fibromyalgia

Front 50

No structural abormalities, most common in middle aged women. NOT associated to rectal bleeding, anemia, weight loss, anemia, increased inflammatory markers, electrolite abnormalities.

Back 50

Irritable bowel syndrome

Front 51

How is irritable bowel syndrome treated?

Back 51

Treat symptoms, dietary modification (avoid lactose, gluten), fibery supplement, antispasmotics, antidepressants, guanylate cyclase agonists (if there is intermittent constipation)

Front 52

What is the main cause of appendicitis in children?

Back 52

lymphoid hyperplasia

Front 53

What is the main cause of appendicitis in adults?

Back 53

Fecalith

Front 54

Where is the appendix located?

Back 54

1/3 distance from anterior superior iliac spine to umbilicus

Front 55

What other pathologies must be considered when diagnosing a possible appendicitis?

Back 55

Diverticulitis (elderly), ectopic pregnancy (use B-hCG to rule out)

Front 56

Persistance of the vitelline duct

Back 56

Meckel diverticulum

Front 57

What are the symptoms and complications of meckel diverticulum?

Back 57

Melena, RLQ pain, intussusception, volvulus, obstruction near the terminal ileum.

Front 58

What are the five 2's of meckel diverticulum?

Back 58

2 inches long

2 feet from ileocecal valce

2% of population

Commonly in the first 2 years of life

2 types of epithelia (gastric, pancreatic)

Front 59

What is technetium scintigraphy?

Back 59

To identify areas of ectopic gastric mucosa

Front 60

What is the most common congenital anomaly of the GI tract?

Back 60

Meckel diverticulum

Front 61

Telescoping of 1 bowel segment into distal segment, commonly at ileocecal junction

Back 61

Intussusception

Front 62

In what population is intussesception most common?

Back 62

Children

Front 63

Twisting of portion of bowel around its mesentery; can lead to obstruction and infarction

Back 63

Volvulus

Front 64

What portion of GI tract is most commonly affected by volvulus in children?

Back 64

Midgut

Front 65

What portion of GI tract is most commonly affected by volvulus in the elderly?

Back 65

Sigmoid

Front 66

Small bowel tumors which secrete high levels of serotonin

Back 66

Carcinoid syndrome

Front 67

What is the most common malignancy in the small intestine?

Back 67

Carcinoid syndrome

Front 68

What are the most common locations for carcinoid syndrome to develop?

Back 68

Bronquial tree, small intestine, appendix

Front 69

What are the symptoms of carcinoid syndrome?

Back 69

Broncospam, flushing, diarrhea, right sided heart disease

Front 70

In what pathologies is meconium ileus commonly seen?

Back 70

Cystic fibrosis and hirschsprung disease

Front 71

In what population is necrotizing enterocolitis seen?

Back 71

Neonats, most common in preemies (due to decreased immunity)

Front 72

What are the symptoms of a patient with necrotizing enterocolitis?

Back 72

Perforation, feeding intolerance, increased gastric residuals, abdominal distention, bloody stools.

Front 73

Tortuous dilation of vessles leading to hematochezia. Most common in cecum, terminal ileum and ascending colon. Older patients.

Back 73

Angiodysplasia

Front 74

Lack of peristalsis in GI tract, post surgical or severe illness. Caused by decreased blood flow to the gut.

Back 74

Intestinal ileus

Front 75

What are the most common causes of small bowel obstruction?

Back 75

A: Adhesion (due to previous surgeries-75% of all cases)

B: Bulge (Hernia)

C: Cancer/tumors

Front 76

How does bowel obstruction caused by cancer/tumors look on xray?

Back 76

Dilated loops of bowel, paucity of gas, pneumatosis intestinalis

Front 77

What are the most common GI problems seen in patients with down syndrome?

Back 77

Duodenal atresia hirschsprung disease, annular pancreas, celiac disease

Front 78

What is the most abundant microorganism in the intestine?

Back 78

Bacteroids fragilis

Front 79

What is the 2nd most abundant microorganism in the intestine?

Back 79

E. coli