GI Path+Micro Flashcards
Pathology?
small bowel obstruction
dilated loops of small bowel, paucity of bowel gas distally
normal for comparison
Pathology?
pneumoperitoneum (free intraperitoneal air)
causes: rupture of hollow viscus, ulcer, tumor, trauma, instrumentation, post-operative (expected up to 5-7 days), necrotizing enterocolitis (neonatal setting)
Pathology/imaging?
Meckel’s scan to look for presence of ectopic mucosa in large bowel
H. pylori-induced ulcers are treated with [?]
PPI + 2 antibiotics (clarithromycin + ampicillin or metronidazole)
Pathology? (salivary glands)
chronic sialadenitis
Pathology?
mucocele
due to blockage or rupture of salivary gland duct with leakage of saliva into surrounding CT stroma
Pathology? (salivary glands)
Sjogren’s syndrome
lymphoid infiltration of lacrimal and salivary glands by activated CD4+ T cells and B cells
Pathology? (salivary glands)
pleomorphic adenoma
most common salivary gland neoplasm; “benign mixed tumor”
Pathology? (salivary glands)
pleomorphic adenoma
distinctive magenta-colored fibrils on diff-quik stain when doing fine needle adenoma
Pathology? (salivary glands)
Warthin’s tumor
aka papillary cystadenoma lymphomatosum
benign tumor
Pathology? (salivary glands)
mucoepidermoid carcinoma
most common malignant neoplasm of salivary gland (46% in minor salivary gland)
Pathology? (salivary glands)
adenoid cystic carcinoma
cribriform architectural pattern; malignant
Pathology? (salivary glands)
acinic cell carcinoma
malignant
Pathology?
achalasia
bird beak sign on barium swallow
Pathology (esophagus)
esophageal varices
Pathology? (esophagus)
GERD
see basal zone hyperplasia
Pathology? (esophagus)
Barrett esophagus
salmon colored, tongue-like area of columnar epithelium
Pathology? (esophagus)
adenocarcinoma of esophagus
most arises from Barrett’s esophagus
Pathology? (esophagus)
squamous cell carcinoma of esophagus
exposure to dietary/ environmental carcinogens
Pathology? (esophagus)
squamous cell carcinoma of esophagus
exposure to dietary/ environmental carcinogens
Pathology? (stomach)
ulcers
Pathology? (stomach)
H. pylori infection
Pathology? (stomach)
ulcer
Pathology? (stomach)
Menetrier disease
excess secretion of TGF-alpha => diffuse hyperplasia of body and fundus foveolar epithelium => enlarged rugae
Pathology? (stomach)
Zollinger Ellison syndrome
gastric gland hyperplasia due to excessive gastrin secretion by pancreas
Pathology? (stomach)
diffuse adenocarcinoma
see signet ring cells (tumor cells containing mucin); gross thickening of gastric wall due to desmoplastic reaction
Pathology? (stomach)
intestinal type adenocarcinoma
predominates in high-risk areas; gland formation on microscopy; bulky tumor
Pathology
Meckel’s diverticulum
failure of involution of omphalo-mesenteric duct
Pathology?
Hirschsprung disease (congenital aganglionic megacolon)
Pathology? (intestines; left normal)
celiac
Pathology? (intestines)
abetalipoproteinemia
enterocyte vacuolization
Pathology? (intestines)
giardia lamblia
Pathology? (appendix)
carcinoid tumor
Pathology? (colon)
juvenile polyp
Pathology?
Peutz-Jegher syndrome
melanotic mucosal and cutaneous pigmentation; hamartomatous polyps throughout GIT
Pathology? (colon)
Crohn’s disease
skip lesions (not continuous); cobblestone appearance
Pathology? (colon)
Crohn’s disease
granulomas in colon
Pathology? (colon)
ulcerative colitis
continuous lesions
Pathology? (liver)
cirrhosis
Pathology? (liver)
cholestasis
brown bile pigment inside hepatocytes, feathery degeneration
Pathology? (liver)
primary sclerosing cholangitis
Pathology? (liver)
hepatocellular carcinoma
malignant; increased AFP
Pathology? (liver)
fibrolamellar carcinoma
can see scarring from fibrosing bands of collagen
Pathology? (liver)
focal nodular hyperplasia
Pathology?
cholesterosis aka strawberry gallbladder
accumulation of cholesterol esters and triglycerides in macrophages within lamina propria
Pathology? (gallbladder)
gallbladder carcinoma
Pathology?
acute pancreatitis
Pathology? (pancreas)
intraductal papillary mucinous neoplasm
can progress to invasive cancer
LFT abnormalities: predominant hepatocellular injury
increased transaminases (ALT, AST)
ALP increased 2-3 times ULN
LTF abnormalities: predominant cholestatic pattern
ALP increased 3-5x ULN
minor transaminase increase
Gilbert’s syndrome
benign AD disorder; partial defect in BRN conjugation and decreased uptake of conjugated BRN by hepatocytes
Crigler-Najjar syndrome
impaired conjugation of BRN; rare; AR (much more deadly) or AD
congenital causes of conjugated hyperbilirubinemia
Dubin-Johnson syndrome, Rotor’s syndrome, progressive familial intrahepatic cholestasis/Byler’s disease
all are AR
[?] naked, segmented ds RNA virus; most common cause of infantile diarrhea
rotavirus
[?] small, round, naked, ss RNA virus; 60% of non-bacterial diarrhea in adults
norovirus/norwalk virus
organisms that grow green-black colonies with metallic sheen on eosin-methylene blue agar
strong lactose fermenters: E. coli
organisms that grow pink-purple colonies on eosin-methylene blue agar
intermediate lactose fermenters: Klebsiella, Enterobacter
organisms that grow colorless, transparent colonies on eosin-methylene blue agar
non-lactose fermenters: Salmonella, Shigella
Guillain-Barre syndrome is often preceded by an infection with [?]
campylobacter jejuni
[?] most common roundworm in temperature zones; fecal-oral transmission; diagnosed with scotch-tape test (egg ID)
Enterobius vermicularis (pinworm)
treatment = pyrantel pamoate or mebendazole
[?] football-shaped eggs in feces; heavy infections can show ulceration and hemorrhage
Trichuris trichiuria (whipworm)
treatment = mebendazole
[?] common in tropical or subtropical regions; pneumonitis, GI perforation, bowel obstruction; do not attach to bowel wall
Ascaris lumbricoides (large roundworms)
treatment = mebendazole
[?] cause pneumonia and eosinophilia as larva migrates; may live in host for 8-16 years
hookworms (Nectar americansus, Ancylostoma dudenale)
treatment = mebendazole
[?] filariform larvae infiltrate through skin, migrate through lungs, and eventually to small intestine
Strongyloides stercoralis (small roundworms)
[?] lemon shaped; presents with diarrhea and muscle paralysis (due to larvae converting muscle cells to nurse cells); spread from eating pork
Trichinella spiralis
[?] nematode parasite of cats and dogs; most infections are asymptomatic
Toxocara
[?] filarial nematodes that cause tropical pulmonary eosinophilia and elephantiasis due to lymphatic obstruction
Wuchereria bancroftii, Brugia malayi
[?] filarial nematode spread by Simulium black flies; causes river blindness
Onchocerca volvus
[?] filarial nematode spread by Chrysops mango flies; migration is not painful but is noticed when they transverse conjunctival tissue
loa loa (African eye worm)
[?] crustacean intermediate; huge quantities of larvae released when worm contacts water through ulcer
Dracunculus medinensis
[?] snails release cercariae, which penetrate skin and develop in veins
Schistosomes (S. mansoni, S. japonicum, S. hematobium)
treated with praziquantel
[?] scrolex and proglottids; cause anorexia and diarrhea; spread by undercooked beef
Taenia saginata (tapeworm)
[?] scrolex and proglottids; cause anorexia, diarrhea, blindness, and neurological disorders; spread by undercooked pork
Taeniea solium (tapeworm)
[?] scrolex and proglottids; cause fluid-filled cysts in liver and lungs; contain hydatid sand
Echinococcus granulosus (rarely in North America)
[?] scrolex and proglottids; spread by eating undercooked fish; can cause vitamin B12 deficiency
Diphyllobothrium lattum (fish tapeworm)
[?] parasite; causes diarrhea, flatulence, cramps, pneumonia, empyema, peritonitis, chronic pericardial infection; cyst disintegrates in small intestine and releases 8 trophozoites
Entamoeba histolytica
treatment = metronidazole, iodoquinol
[?] parasite; binucleated flagellate with 4 pairs of flagella; cause sudden onset explosive diarrhea, greasy foul-smelling stools, large amounts of gas; water-borne epidemics
Giardia lamblia
treatment: metronidazole, quinacrine
[?] obligatory intracellular parasites that cause explosive, perfuse, watery diarrhea, weight loss, wasting, and death in the immunocompromised
Cryptosporidium
no treatment available
[?] causes food poisoning via enterotoxins A-D, which induce intestinal peristalsis and stimulate vomit reflex => nausea, vomiting, cramps, watery non-bloody diarrhea, profuse sweating, headache 1-6 hours after eating
Staph aureus
[?] form spores that can survive on grain foods (rise) and some meet dishes
Bacillus cereus
the emetic type of Bacillus cereus food poisoning is caused by [?], while the diarrheal type is caused by [?]
the emetic type of Bacillus cereus food poisoning is caused by heat-stable enterotoxin, while the diarrheal type is caused by heat-labile enterotoxin
heat-labile has longer incubation period (24 hours) and involves increased cAMP production
[?] germination of spores in alkaline foodstuffs causes food-borne illness (12-36 hour incubation) and descending paralysis
C. botulinum
[?] ingestion of spore-contaminated meat dishes results in production of heat labile enterotoxin => diarrhea within 18 hours of ingestion
Clostridium perfringes