Anus, Peritoneum and Gallbladder

Question 1

What causes hemorrhoids?

Answer 1

Increased venous pressure within the hemorrhoidal plexus

Question 2

What 3 predisposing conditions/diseases can cause hemorrhoids?

Answer 2

Straining at the toilet due to constipation

Pregnancy

Portal HTN

Question 3

What is the difference between internal and external hemorrhoids?

Answer 3

Internal - painless and can be treated without anesthesia (above the pectinate line)

External - very painful and require anesthesia (below pectinate line)

Question 4

What are the 3 zones of the anal canal and what are the epithelium types?

Answer 4

Upper zone: columnar epithelium

Middle zone: transitional epithelium

Lower zone: stratified squamous epithelium

Question 5

What are cancers below the pectinate line typically?

Above the pectinate line?

Answer 5

Below the pectinate line: squamous cell carcinomas (basal cell carcinoma and melanoma) - HPV-16 association

Above the pectinate line: adenocarcinomas

Question 6

Which lymph nodes does anal cancers most often spread?

Answer 6

Superficial inguinal LNs

Question 7

Appendicitis is most common in which patients?

Answer 7

Younger patients, M>F

Question 8

What is on the DDx for acute appendicitis? (5)

Answer 8

Yersinia infection (mesenteric lymphadenitis)
Acute salpingitis
Ectopic pregnancy
Mittelschmerz
Meckel diverticulum

Question 9

What initiates an appendicitis?

Answer 9

Progressive increases in intraluminal pressure that compromises venous outflow

Question 10

What processes lead to inflammation in an appendicitis?

Answer 10

50-80% occur due to overt luminal obstruction, usually due to a small piece of stool, fecalith or, less commonly, a gallstone or mass of worms.

Question 11

How does stasis affect the inflammatory process in an appendicitis?

Answer 11

It increases the risk for infection and triggers inflammatory responses and ischemia, along with a neutrophilic infiltrate to the surrounding tissues.

Question 12

What are symptoms of appendicitis?

Answer 12

RLQ pain, followed by nausea, vomiting, low-grade fever and mildly elevated WBC ct.

Question 13

A diagnosis of appendicitis requires what?

Answer 13

Neutrophilic infiltrate of the muscularis propria

Question 14

What is the most common tumor of the appendix?

Answer 14

Well-differentiated neuroendocrine (carcinoid) tumor

Question 15

What is an appendix mucocele? What causes it? (2)

Answer 15

A dilated appendix filled with mucin, which might be due to an obstructed appendix containing mucous, or as a consequence of mucinous cystadenoma.

Question 16

What can occur as a result of` mucinous cystadenoma?

Answer 16

Invasion through the appendiceal wall

Question 17

What causes a pseudomyxoma peritonei?

Answer 17

Mucinous cystadenoma causes the abdomen to fill with semisolid mucin and leads to pseudomyxoma peritonei and follows a fatal course

Question 18

What can cause peritoneal inflammation?

Answer 18

Bacterial invasion or chemical irritation

Question 19

List 7 causes of peritoneal inflammation

Answer 19

Leakage of bile and pancreatic enzymes, producing sterile peritonitis

Perforation or rupture of the biliary system, which can be complicated by a secondary bacterial infection

Acute hemorrhagic pancretitis - leakage of pancreatic enzymes and fat necrosis

Foreign material

Endometriosis

Ruptured dermoid cyst

Perforation of abdominal viscera

Question 20

What causes a peritoneal infection?

Answer 20

Bacteria from the GI lumen are released into the abdominal cavity, most commonly following a perforation

Question 21

What 5 bacteria are most often implicated in peritonitis?

Answer 21

E. coli

Streptococci

S. aureus

Enterococci

C. perfringens

Question 22

What characterizes sclerosing retroperitonitis?

Answer 22

Dense fibrosis that may extend to involve the mesentery

Question 23

What group of diseases is sclerosing retroperitonitis in?

What structure is most commonly affected?

Answer 23

IgG4-related disease

Ureters

Question 24

What is the most common malignancy of the peritoneum? What is the most common sub-type?

Answer 24

Mesotheliomas - most commonly, the desmoplastic small round cell tumors, which occur in kids and young adults

Question 25

What is the most common congenital anomaly of the Gb?

Answer 25

A phyrgian cap, due to a folded fundus

Question 26

What are the 2 types of choleliths?

Answer 26

Cholesterol stones and Pigment stones

Question 27

What ethnicities are associated with Cholesterol stones and Pigment stones?

Answer 27

Cholesterol stones: Northern Europeans, North and South Americans, NA, Mexicans Pigment stones: Asians, rural>urban

Question 28

What are some risk factors for cholesterol stones? (4)

Answer 28

Increased age Female sex hormones (OCs and pregnancy) Obesity and metabolic syndrome Rapid weight loss

Question 29

What 3 structural/anatomical changes can increase the risk for cholesterol stones?

Answer 29

Gb stasis Inborn errors of bile acid metabolism Hyperlipidemia syndromes

Question 30

What are 3 causes of pigment stones?

Answer 30

Chronic hemolytic syndromes Biliary infections GI disorders: CD, ileal resection/bypass, CF with pancreatic insufficiency

Question 31

Cholesterol stones occur when...

Answer 31

Cholesterol concentrations exceed the solubilizing capacity of bile (supersaturation)

Question 32

Which stones are exclusively in the Gb?

Answer 32

Cholesterol stones

Question 33

What do cholesterol stones look like?

Answer 33

Pale yellow, round to ovoid and have a fine/granular, hard external surface Multiple stones develop often

Question 34

What causes Pigment stones?

Answer 34

Increased unconjugated bilirubin

Question 35

What 3 infections are implicated in pigment stones?

Answer 35

E. coli Ascaris lumbricoides C. sinensis

Question 36

What is the appearance of pigment stones? Where are they found?

Answer 36

Black stones: found in sterile Gb bile Brown stones: found in large infected bile ducts

Question 37

What is the major symptom of gallstones?

Answer 37

Biliary colic - RUQ pain following a fatty meal Many may exist asymptomatically for years and remain that way

Question 38

What are complications of gallstones? (5)

Answer 38

``` Empyema Perforation Fistulas Inflammation of biliary tree Inflammation of the pancreas ```

Question 39

Acute cholecystitis is precipitated by what?

Answer 39

Precipitated by obstruction of the neck or cystic duct by a stone

Question 40

What are some symptoms of acute cholecystitis?

Answer 40

RUQ pain for 6 hrs. | -mild fever, anorexia, tachycardia, sweating, N/V

Question 41

Which type of cholecystitis does not often cause jaundice?

Answer 41

Acute cholecystitis does not cause jaundice

Question 42

What lab abnormalities are seen in acute cholecystitis?

Answer 42

Mild leukocytosis and mild elevation of serum alkaline phosphatase

Question 43

What is the pathophysiology of acute calculous cholecystitis?

Answer 43

Chemical irritation and inflammation of the Gb obstructed by a stone - occurs in the absence of bacterial infection

Question 44

What patients are most likely to have acute calculous cholecystitis?

Answer 44

Diabetics with symptomatic gallstones

Question 45

What is the cause of acute acalculous (w/o stone involvement) cholecystitis?

Answer 45

Thought to be from ischemia

Question 46

What is the morphology of the Gb in acute chgolecystitis?

Answer 46

Gb is enlarged and tense in acute cholecystitis

Question 47

# Define the following: Gb empyema Gangrenous cholecystitis Acute emphysematous cholecystitis

Answer 47

Gb empyema: occurs when the Gb fills with fibrin and pus in calculous cholecystitis Gangrenous cholecystitis: when the Gb is transformed into a green-necrotic organ Acute emphysematous cholecystitis: when there is invasion of gas-forming organisms

Question 48

What is the most common cause of chronic cholecystitis?

Answer 48

It is often asequel to repeated bouts of mild to severe acute cholecystitis, but can also be without precipitating cause

Question 49

Chronic cholecystitis is associated with what?

Answer 49

Gallstones in 90% of cases

Question 50

What 2 bugs can be cultured in 1/3 of chronic cholecystitis cases?

Answer 50

E. coli and enterococci

Question 51

What may exist morphologically in chronic cholecystitis? (3)

Answer 51

Subserosal fibrosis Rokitansky-Aschoff sinuses - outpouchings of mucosal epithelium through the wall In rare cases - extensive dystrophic calcification within the Gb, which yields a "porcelain Gb" and increases the risk of cancer

Question 52

What is Xanthogranulomatous cholecystitis?

Answer 52

Occurs in chronic cholecystitis when the Gb has a massively thickened wall and is shrunken, inflamed and necrotic

Question 53

What is hydrops of the gallbladder?

Answer 53

Occurs in atrophic, chronically obstructed, often dilated Gb that contains clear secretions

Question 54

What patient population is most commonly affected by Gb carcinoma?

Answer 54

>2x more common in females, especially in NA, Hispanic and Latin ethnicities

Question 55

What is the most important risk for Gb cancer? What is the most common cancer?

Answer 55

Gallstones Adenocarcinomas

Question 56

What is the prognosis of Gb cancers?

Answer 56

Hard to say - by the time they've been found, they have often metastasized to the liver and invaded the cystic duct and nearby bile ducts and portal-hepatic lymph nodes

Question 57

What are the 2 patterns of growth in Gb cancer? What is their appearance?

Answer 57

Infiltrating pattern - more common and appears as a poorly defined area of diffuse mural thickening and induration Exophytic pattern - grows into tge lumen as irregular "cauliflower mass", but also invades the underlying wall