Inflammation, Infection, & Repair (lab) Flashcards
What are some macroscopic indicators for appendicitis?
- Increased Size
- White/Grey Mesentery
- Thickened appendix wall with dusky appearance
- Often contains fibrinopurulent exudate (pus)
What are some microscopic indicators for appendicitis?
Ulcerated epithelium (appreciated on low magnification) Increased neutrophils
What cells line the mesenteric surface of the appendix?
Mesothelial cell
What are some ACUTE findings of appendicitis?
Acute:
• Robust inflammatory cell infiltrate
• Predominantly neutrophils present in lamina propria and muscular wall
• Presumed edema within the appendix wall due to increased permeability of blood vessels
What are some CHRONIC findings of appendicitis?
• Reactive epithelial cell changes (loss of columnar shape, mucin depletion)
• Some admixed mononuclear cells are identified among the inflammatory infiltrate
• Evidence of early repair (mitotic figure in Image 5B is most likely is that of an
endothelial cell indicating early neovascularization)
What is the PATHOGENESIS (progression pathway of disease) of appendicitis?
- Obstruction by fecalith (common)
- Continued secretion of mucus with increased intraluminal pressure
- Bacterial proliferation
- Ischemic injury due to distention and increased intraluminal pressure which compromises blood
flow
What are the main concerns after you rupture your appendix?
Rupture of the appendix – or any visceral structure – can lead to the spilling of bacteria onto the peritoneal surface and stimulation of an inflammatory response
o Peritonitis - bacterial
o Adhesions secondary to the repair process can lead to complications
What is the difference between Cholelithiasis and Cholecystitis?
Cholelithiasis: Gallbladder stones
Cholecyst ITIS: Inflammation of the gall bladder (typically as a result of gall bladder stones blocking the biliary pathway promoting inflammation etc.
What are the gross features of cholecystitis?
- Marked increase in size of patient’s gallbladder
- Dusky serosal surface
- Large stones (choleliths) present
- Hemorrhagic mucosa with fibrinopurulent exudate (in contrast to normal “velvety green” appearance of control) - Apparent thickening of wall - chronic change
What are the histological features of cholecystitis at LOW magnification?
- Vascular congestion; some possible hemorrhage in the deep muscle and serosal areas
- Marked hypertrophy of smooth muscle bundles
- Loss of delicate villous architecture
- Adherent adipose tissue
What are the histological features of cholecystitis at HIGH magnification?
- Neutrophils in lumen = fibrinopurulent exudate
- Loss of surface mucosa with inflammatory cells = ulceration
- Regenerative appearance of adjacent, intact mucosa - Neutrophil infiltrate in the mucosa and submucosa
What is the pathophysiology (disease pathway) of cholecystitis?
- Outlet obstruction due to lodging of a stone in the gallbladder neck or cystic duct
- Mucosal epithelium is damaged due to direct detergent action of bile salts
- Distention and increased intraluminal pressure compromise blood flow to the mucosa
- Smooth muscle hypertrophy takes place
What are the macroscopic signs of a cirrhotic liver?
- Patient’s liver reduced in size / shrunken with a nodular surface
- Fibrotic bands demarcating the “regenerative nodules”
- Yellow-appearance to cut surface, consistent with fatty change / steatosis.
What are the microscopic signs of a cirrhotic liver?
- Nodules of hepatic parenchyma are surrounding by dense bands of fibrosis with probably inflammation
- Portal triads and central veins are difficult to discern
What is the relationship between liver cirrhosis and EtOH (alcohol) abuse?
- Steatosis (lipid accumulation in hepatocytes) can be centrilobular or involving the entire lobule
- Alcoholic hepatitis with hepatocyte swelling and necrosis, reactive inflammation, and Mallory body formation.
