9 - Appendix and Peritoneum Flashcards
signs/sx of appendicitis
periumbilical pain > RLQ pain, nausea, vomiting, low grade fever, mildly elevated WBC
McBurney’s sign** - tenderness at McBurney’s point
complications of appendicitis
perforation, pyelophlebitis, portal venous thrombosis, liver abscess, bacteremia
path findings in acute appendicitis
congestion of subserosal vessels, modest perivascular neutrophil infiltrate in all layers
dx when neutrophilic infiltrate in muscularis propria
later on develop focal abscesses in wall, areas of hemorrhagic ulceration > necrosis
one of the most common parasites in appendix
enterobius vermicularis (pinworm)
MC tumor of appendix
carcinoid
carcinoid
MC tumor of appendix
well diff neuroendocrine tumor
Female > male
usually incidental finding, carcinoid syndrome is very rare and assoc w/ metastatic dz
path of appendix carcinoid tumor
gross: round w/ gray-yellow cut surface
micro: insular pattern of nests, peripheral nuclear palisading. cells are polyhedral, round/oval nuclei, speckled chromatin, eosinophilic or ampophilic cytoplasm, no necrosis, stroma can become dense and fibrous in larger masses
prognosis for carcinoid in appendix
usually good - metastasis rare, usually only to regional LNs
how do adenoma/adenoCA of appendix usually present?
obstruction/enlargement - mimics appendicitis
mucocele - dilated appendix full of mucin
how do you tell microscopically if the cells of the peritoneum are irritated?
flat at rest, round/columnar when irritated
may even proliferate to form multiple layers if severe
mesothelial cells have ___ and ____
intercellular jxns
microvilli
most common bacteria (2) infecting peritoneum
e coli
enterococcus
sx of peritonitis
severe abd pain, distention, N/V/D
major causes of peritonitis
peptic ulcer, appendicitis, diverticulitis, cholecystitis, gangrenous obstruction of small intestine
acutely, peritonitis can look like what microscopically?
layers of neutrophils on top of reactive mesothelium
