Intra Abdominal Infections - (GI Pathology)

Question 1

What is the definition of an intra abdominal infection?

Answer 1

• Presence of micro-organisms in normally sterile sites within the abdominal cavity.
• Peritoneal cavity and hepatobiliary tree

Question 2

Why is the stomach and proximal intestine relatively sterile?

Answer 2

Stomach - Acid

Proximal Small Intestine- bile inhibits growth.

Question 3

what kind of organisms reside in the large intestine?

Answer 3

• Mostly Anaerobic bacteria

- Aerobic Bacteria are Enterobacteriaceae and Gram positive cocci such as enterococci.

Question 4

What are common sources of intra abdominal infection? and how do microorganisms enter?

Answer 4

1) Blood

2) GI :
- contents go into peritional cavity via fistula or perforation

-microorganisms move along lumen to hepatobiliary tree.

Question 5

How are organisms translocated across the wall?

Answer 5

1) Perforated appendix

2) Perforated diverticulum (usually occurs in sigmoid and descending colon)

Question 6

How does bowel cancer cause intra-abdo infections?

Answer 6

Abnormal / malignant tissue can cause the bowel wall to lose integrity allowing contents to escape.

Question 7

How does Ischaemia cause Intra-abdo infection?

Answer 7

Interuption of intestinal blood supply can cause the gut wall to necrose and lose structural integrity.

Question 8

What is Cholecystitis?

Answer 8

Inflammation of the gallbladder wall.

Question 9

What causes Cholecystitis?

Answer 9

Obstruction of the cystic duct can cause by gallstones or malignancy.

Question 10

How does cholecystitis present?

Answer 10

• fever
• pain in right upper quadrant.
• jaundice

Question 11

What are the complications of Cholecystitis?

Answer 11

Empyema of gallbladder.

Collection of pus in gallbladder.

Question 12

What is Cholangitis?

Answer 12

Inflammation / Infection of Biliary Tree.

Question 13

What is the cause of Cholangitis?

Answer 13

Obstruction of common bile duct

Question 14

How does Cholangitis present?

Answer 14

• fever
• rigors
• jaundice
• Right upper pain

Question 15

What is Pyogenic liver abscess?>

Answer 15

It is an abscess caused by bacterial infection.

Question 16

What are the routes of infection that cause pyogenic liver abscess?

Answer 16

• Biliary Obstruction
• Direct spread from other intra-abdo infections.
• Haematogenous:
• from mesenteric infection
• hepatic artery.

Question 17

What is an Intra-Peritioneal Abscess?

Answer 17

localised area of inflammation with a build up of pus.

Question 18

What are the pre-disposing factors of an intra-peritoneal abscess?

Answer 18

1) Perforation via:
- peptic ulcer
- perforated appendix
- Perforated diverticulum

2) Cholecystitis
3) Mesenteric Ischaemia
4) Pacreatitis / necrosis

Question 19

How does an intra peritoneal abscess present?

Answer 19

1) Subphrenic abcess
- pain in shoulder on affected side.
- hiccups
- hepatomegaly

2) Pelvic abscess
- urinary frequency

Question 20

What is spontaneous bacterial peritonitis?

Answer 20

Infected Ascitic Fluid

*Ascitic fluid is lies between the 2 layers of peritoneum

Question 21

E.coli, Enterobacter, Citrobacter and Pseudomonas spp are all examples of what type of bacteria?
*aerobic Gram-ve bacili,/anaerobic gram-ve bacili/ aerobic gram+ve cocci/Anaerobi gram+ve bacilli

Answer 21

Aerobic Gram negative Bacilli

Question 22

what type of bacteria is Enterococcus spp

Answer 22

Aerobic gram +ve cocci