Pathoma - Small Bowel, Appendix, Ibd - Fundamentals Of Pathology

Front 1

What is duodenal atresia?

Back 1

Congenital failure of small bowel to canalize.

Front 2

Duodenal atresia is associated with what?

Back 2

Down syndrome

Front 3

Clinical features of duodenal atresia?

Back 3

(1) Polyhydramnios (can't digest amniotic fluid)
(2) Distension of stomach and blind loop duodenum of duodenum ('double-bubble' sign)
(3) Bilious vomiting

Front 4

What is a Meckels diverticulum?

Back 4

Outpouching of all three layers of bowel wall. Arises due to failure of vitelline duct to involute.

Front 5

Meckel diverticulum is a __________ (true/false) diverticulum.

Back 5

true

Front 6

Early in embryologic life, the midgut receives it's nutrients from the _____________, and the way by which it receives this is through the ___________.

Back 6

yolk sac; vitelline duct

"The vitelline duct is 'vital' for receiving nutrients early in life"

Front 7

The vitelline duct normally forms around the _______ week and involutes around the _______ week.

Back 7

4th; 7th

Front 8

What complication may arise in an vitelline duct that hasn't involuted at all.

Back 8

Passing of meconium through umbilicus

Front 9

On physical exam how would Meckels diverticulum present?

Back 9

Something hard but soft (stool) in umbilical area.

Front 10

Rule of 2's with Meckels diverticulum.

Back 10

(1) Seen in 2% of population.
(2) 2 inches long
(3) located in bowel within 2 feet of the ileocecal valve
(4) presents during first 2 years of life

Front 11

What is the MC congenital anomaly of the GI tract?

Back 11

Meckels diverticulum

Front 12

Clinical presentation of Meckels diverticulum?

Back 12

(1) Bleeding, volvulus, intussusception, or obstruction during first 2 years of life.

Most cases are however asymptomatic.

Front 13

Why can we see bleeding inside a Meckels diverticulum?

Back 13

Heterotopic gastric mucosa may be present (choristoma)

Front 14

What is volvulus?

Back 14

Twisting of bowel along its mesentery. Results in obstruction and disruption of blood supply (infarction).

Front 15

Most common locations for a volvulus to occur?

Back 15

(1) Sigmoid colon (elderly)
(2) Cecum (young adults)

Front 16

What could this be? What type of infarction is it?

Back 16

Volvulus. Hemorrhagic.

Front 17

What is intussusception?

Back 17

Telescoping of a proximal segment of bowel into a more distal segment of bowel.

Front 18

Patients with intussusception often present with?

Back 18

When the segment telescopes, blood supply is compressed. Presents with obstruction or with infarction. Infarction often presents itself with something called current gelly stools.

Front 19

Intussusception is associated with _____________.

Back 19

a leading edge; it needs something to "hook on" to create a leading edge

Front 20

What may create a leading edge for intussusception to occur?

Back 20

(1) In children, the MCC is lymphoid hyperplasia (TI to cecum)
- Infection causes hyperplasia and terminal ileum gets dragged.
(2) In adults, MCC is tumor.

Front 21

The small bowel is __________ (not/mildly/highly/ susceptible to ischemic injury.

Back 21

highly. It needs tons of ATP (it performs a lot of digestion and absorption). Mucosal infarction can occur with marked hypotension.

Front 22

What could occur when you get ischemia of the small bowel? Describe the etiologies for each scenario.

Back 22

(1) Transmural infarction may occur. Occurs with thrombosis or embolism of SMA or thrombosis of mesenteric vein.
(2) Mucosal infarction. Occurs with marked hypotension.

Front 23

An elderly man appears apathetic. He appears to have lower than normal muscle strength. He is also known to have heart problems and he has a goiter. Lately, whenver he eats he experiences a stabbing pain in his abdomen. What could be the cause?

Back 23

Graves' disease in the elderly (apathetic hyperthyroidism) tend to have atrial fibrillation and congestive heart failure. A-fib can cause clot formation which could embolize, lodge in SMA and cause bowel infarction.

Front 24

A middle-aged man has had recent episodes of bloody diarrhea. He has a long history of skin ulcers and pain in his testicles. His history is significant for hepatitis B infection. What could have caused this diarrhea?

Back 24

Vasculitis of SMA with thrombosis and infarction of bowel.

Front 25

A man with a constantly ruddy face now has migraine attacks and blurred vision. He tells you this followed his recent episode of melena.

(1) Why did he have melena?
(2) What is a very common initial complaint in this disorder?
(3) What other patient could have melena with the same etiology as in this disorder?

Back 25

(1) Thrombosis of IMV, he has polycythemia vera.
(2) Pruritus after bathing.
(3) Lupus (lupus anticoagulant)

Front 26

Clinical features of small bowel infarction?

Back 26

(1) Abdominal pain
(2) Bloody diarrhea
(3) Decreased bowel sounds

Front 27

Upon consumption of milk products a man has abdominal distension and diarrhea. What is it?

Back 27

Lactose intolerance (decreased function of lactase in brush border of enterocytes)

Front 28

True or false: Lactose intolerance is always congenital.

Back 28

False, it may be congenital or acquired (As you age or after GI infection)

Front 29

Lactose is broken down into what?

Back 29

Galactose and glucose

Front 30

What is celiac disease?

Back 30

Immune-mediated damage of small bowel villi due to gluten exposure.

Front 31

Celiac disease is associated with what human leukocyte antigens?

Back 31

(1) HLA DQ2
(2) HLA DQ8

Front 32

Gluten is present in _________ and __________.

Back 32

wheat (hvete); grain (korn)

Front 33

This is the most pathogenic component of gluten. What happens inside the enterocyte?

Back 33

Gliadin.

Gliadin is deamidated by tissue transglutaminase. Deamidated gliadin is presented by APCs via MHC II. Helper T cells help mediate the damage.

Front 34

Classical presentation of celiac disease in children and adults?

Back 34

(1) Children: abdominal distension, diarrhea, failure to thrive
(2) Adults: chronic diarrhea, bloating

Front 35

One associated finding with celiac disease. Describe.

Back 35

Dermatitis herpetiformis. Due to IgA deposition at tips of dermal papillae, disrupts connection between dermis and epidermis between those points. This results in a blister or vesicle that looks like the vesicles in herpes. Resolves with gluten free diet.

Front 36

Laboratory findings in celiac disease?

Back 36

(1) IgA antibodies against endomysium, tTG or gliadin.

Front 37

A subset of patients with celiac disease can be IgA deficient. What laboratory tests can we employ to test for celiac disease in these patients?

Back 37

IgG antibodies.

Front 38

How do we make a diagnosis of celiac disease? What will it show?

Back 38

Duodenal biopsy.

Flattening of villi, hyperplasia of crypts, increased intraepithelial lymphocytes (normally we have villi that protrudes and tiny villi that dips down)

Front 39

What is the damage distribution in celiac disease?

Back 39

Most prominent in the duodenum. Jejunum and ileum are less involved.

Front 40

Most important diagnostic antibody in celiac disease?

Back 40

Anti-tissue transglutaminase IgA

Front 41

A woman with gluten-free diet for many years presents with celiac disease again. It is refractory to any dietary changes. What could have happened?

Back 41

Small bowel carcinoma or T-cell lymphoma (Enteropathy associated T-cell lymphoma; EATL)

Front 42

Tropical sprue is similar to celiac disease, however it is due to?

Back 42

an unknown organism

Front 43

Tropical sprue results in __________.

Back 43

malabsorption and diarrhea

Front 44

Tropical sprue is similar to celiac sprue, except [...]

Back 44

(1) Tropical sprue occurs in tropical regions (e.g., caribbean)
(2) Arises after infectious diarrhea and responds to antibiotics
(3) Damage is most prominent in jejunum and ileum; duodenum is less commonly involved

Front 45

What nutritional deficiencies could you theoretically get in tropical sprue?

Back 45

Jejunum is affected --> Folic acid deficiency
Ileum is affected --> B12 deficiency

Front 46

What is Whipple's disease?

Back 46

Systemic tissue damage characterized by macrophages loaded with Tropheryma whippelii organisms.

Front 47

What stain would you use (1) and WHAT are you staining when looking for the etiology of Whipple's disease (2)?

Back 47

(1) PAS
(2) Partially destroyed organisms are present in macrophage lysosomes (positive for PAS)

Front 48

What is the classic site of involvement in Whipple's disease? What is the result? Explain the pathology behind fat malabsorption.

Back 48

Small bowel lamina propria. Results in fat malabsorption and steatorrhea.

The macrophages are numerous and compress lacteals, preventing chylomicrons from properly diffusing from enterocytes into lacteals in lamina propria.

Front 49

What is this?

Back 49

Whipple's disease. PAS to the right.

Front 50

The most common site affected in Whipple's disease is the lamina propria of the small bowel, however, what are some other common sites of involvement?

Back 50

(1) Synovium of joints (arthritis)
(2) Cardiac valves
(3) Lymph nodes
(4) CNS

Front 51

What is abetalipoproteinemia? Describe it.

Back 51

AR deficiency of apolipoprotein B-48 and B-100.

B-48
- Can't form chylomicrons (fat malabsorption)
B-100
- Absent plasma VLDL and LDL

Front 52

What is a carcinoid tumor?

Back 52

Malignant proliferation of neuroendocrine cells; low-grade malignancy (high grade would be small cell carcinoma).

Front 53

Carcinoid tumor is positive for ____________.

Back 53

chromogranin

Front 54

Where does a carcinoid tumor arise?

Back 54

Can arise anywhere along the gut (tarm). Small bowel is the MC site.

Remember it like this: Every site in the GI has a cancer associated with it, but not small bowel, so we gotta give it something. We give it this one.

Front 55

What is this?

Back 55

Carcinoid tumor. Grows as submucosal polyp.

Front 56

Carcinoid often secrete what substance and what is it metabolized to?

Back 56

Serotonin; metabolized to 5-hydroxyindoleacetic acid (5-HIAA) by monoamine oxidase which is excreted in the urine.

Front 57

This location is the MC location for a carcinoid tumor. It is usually _______ cm.

Back 57

Vermiform appendix; < 2cm (which is too small for metastasis to liver)

Front 58

From what location would a carcinoid tumor typically metastasize to the liver from and why?

Back 58

Midgut carcinoid tumors (e.g., terminal ileum) tend to invade and ALSO metastasize. Potential for metastasis increases with size and depth of invasion. It needs to be more than 2 cm and size of invasion must be > 50%.

Front 59

Carcinoid syndrome is characterized by what clinically? What organ can it particularly affect.

Back 59

(1) Bronchospasms
(2) Diarrhea
(3) Flushing of the skin

Right side of the heart. Serotonin causes fibrosis of heart valves.

Front 60

Symptoms of carcinoid syndrome can be triggered by what?

Back 60

(1) Drinking alcohol
(2) Emotional stress

Causes release of serotonin from the tumor.

Front 61

Right sided carcinoid heart disease leads to what?

Back 61

Right-sided valvular fibrosis.

Leads to tricuspid regurgitation and pulmonary valve stenosis.

Front 62

Why don't we get left-sided valvular disease?

Back 62

Serotonin is broken down by MAO in the lung.

Front 63

What is acute appendicitis?

Back 63

Acute inflammation of appendix.

Front 64

What is acute abdomen? (brief)

Back 64

When a patient presents with a severe abdominal pain that is often a surgical emergency.

Front 65

This is the MCC of acute abdomen.

Back 65

Acute appendicitis.

Front 66

What is acute appendicitis related to in children and adults?

Back 66

(1) Related to obstruction of the appendix by lymphoid hyperplasia (children).
(2) In adults it is related to obstruction of appendix by fecalith.

This is a general principle of pathology, you block a tube and you often get infection/inflammation.

Front 67

Pain in acute appendicitis is initially ____________ and then shifts to _______.

Back 67

periumbilical; RLQ

Front 68

What is a very important sign for identifying acute appendicitis in children with abdominal pain?

Back 68

Fever

Front 69

A man with acute appendicitis extends his leg and reports pain. What is this sign called?

Back 69

Psoas sign

Front 70

In acute appendicitis, pain shifts to right lower quadrant (RLQ) in ____ to ____ hours. This is due to what?

Back 70

12;18

Irritation of different nerve fibers. Irritation of A-delta fibers on parietal peritoneum. This localizes pain to exact location.

Front 71

What is Blumberg's sign?

Back 71

Rebound tenderness at McBurney's point.

Front 72

What appears first in acute appendicitis; pain or nausea & vomiting?

Back 72

Pain precedes nausea and vomiting.

Front 73

Rupture of the appendix can result in what?

Back 73

Rupture results in peritonitis that presents with guarding (so much pain that the patient tightens muscles to 'guard') and rebound tenderness.

Front 74

Common complication of acute appendicitis?

Back 74

Periappendiceal abscess.

Front 75

What is IBD? What is its etiology?

Back 75

Chronic relapsing inflammation of bowel. Possibly due to abnormal immune response to enteric flora.

Front 76

Classic presentation of IBD?

Back 76

Young women (teens to 30s) with recurrent bouts (omgang, anfall) of bloody diarrhea and abdominal pain.

Front 77

IBD is more prevalent in the ________, particularly _________ and ____________.

Back 77

West; Caucasians; Eastern European Jews

Front 78

What type of diagnosis is IBD?

Back 78

Diagnosis of exclusion because bloody diarrhea and abdominal pain mimic other causes of bowel inflammation.

Front 79

What does the word ulcerative colitis tell you about the disease itself?

Back 79

Ulcerative tells us about the involvement of the wall; mucosal and submucosal ulcers

Colitis; involves colon

Front 80

Where does UC typically arise? How does it progress in terms of location?

Back 80

Begins in rectum and can extend proximally up to the cecum (involvement is continuous). Remainder of the GI remains unaffected. The most proximal it can go is the cecum.

Front 81

What symptoms do we have in UC?

Back 81

Recurrent LLQ crampy pain (rectum) with mucus and bloody diarrhea.

Front 82

What is the key histologic hallmark of UC?

Back 82

Crypt abscesses with neutrophils.

Front 83

What is the gross appearance of a colon affected by UC?

Back 83

(1) Pseudopolyps (a series of bumps that arise due to healing of the inflammatory process)
(2) Loss of haustra

Front 84

What is this?

Back 84

A colon affected by ulcerative colitis.

Front 85

Complications of ulcerative colitis.

Back 85

(1) Toxic megacolon where patients start to appear toxic (febrile etc).
(2) Rupture
(3) Carcinoma

Front 86

The risk of carcinoma in ulcerative colitis is based on what?

Back 86

(1) Extent of colonic involvement
(2) Duration of disease

Front 87

When is carcinoma in a patient with ulcerative colitis a concern?

Back 87

Generally not a concern until > 10 years of disease.

Front 88

Ulcerative colitis has some associations, what are they?

Back 88

(1) Primary sclerosing cholangitis
(2) p-ANCA positivity

Front 89

Smoking protects against _______ while it exacerbates ______.

Back 89

ulcerative colitis; Crohn's

Front 90

p-ANCA should remind you of what?

Back 90

(1) Microscopic polyangiitis
(2) Churg-Strauss
(3) UC

Front 91

UC is a superficial ulceration while Crohn's disease is a __________.

Back 91

full-thickness inflammation with knife-like fissures

Front 92

What is the typical location of Crohn's disease?

Back 92

MC site is terminal ileum. Can occur anywhere from mouth to anus with skip lesions. Rectum is least common site.

Front 93

Presenting symptoms of Crohn's?

Back 93

RLQ pain (ileum) with non-bloody diarrhea

Front 94

What is the hallmark of Crohn's disease?

Back 94

Lymphoid aggregates with granulomas (40% of cases).

Front 95

Gross appearance of the gut affected by Crohn's?

Back 95

(1) Cobblestone appearance (rullestein/brostein)
(2) Creeping fat (comes closer to serosa due to fibrosis by healing)
(3) Strictures

Front 96

What is this?

Back 96

A classic 'string-sign' characteristic of Crohn's disease. Caused by strictures.

Front 97

Complications of Crohn's disease?

Back 97

(1) Malabsorption with nutritional deficiencies
(2) Calcium oxalate nephrolithiasis
- Normally we have oxalate in gut, but we dont absorb much. Inflammation causes us to absorb more.
(3) Fistula formation
- Weakened wall with rupture that plugs into another tube or epithelial surface.

Front 98

There is a risk of carcinoma in Crohn's however [...]

Back 98

Only if colonic involvement is present

Front 99

Crohn's disease is associated with what?

Back 99

(1) Ankylosing spondylitis
(2) Sacroiliitis
(3) Migratory polyarthritis
(4) Erythema nodosum
(5) Uveitis

Front 100

What is this?

Back 100