GI infections.txt

  1. Name three things that can cause esophagitis?
    Candida, CMV, HSV.
  2. What are three non-invasive tests to diagnose H. pylori?
    Urea breath test, serology, stool antigen test.
  3. What are three invasive tests to diagnose H. pylori?
    Endoscopic: Culture, histology, biopsy urease test.
  4. What is the first line treatment for H. pylori?
    • Two antibiotics: Metronidazole, clarythromycin
    • One PPI: Omeprazole.
  5. What is the measured fecal osmolality in osmotic diarrhea?
    Less than 2.
  6. What does STEC stand for?
    Shiga-toxin producing E. coli - (0157:H7).
  7. What is an unusual feature of E. coli 0157:H7, what medium is used to culture?
    • Does not ferment sorbitol
    • Sorbitol-MacConkey medium (SMAC): clear colonies are 0157.
  8. What are some characteristics of Salmonella?
    Gram negative, flagellated, non-encapsulated, facultative anaerobic bacillus.
  9. Where is salmonella typhi found, where does it multiply in the body, what are some risk factors?
    • Poor sanitation areas
    • Mononuclear phagocytic cells
    • HIV, decreased gastric pH.
  10. What are the four most common symptoms of typhoid?
    • Fever, weakness, anorexia, headache
    • Less common: abdominal pain, diarrhea, constipation.
  11. What are some characteristics of Shigella dysenteriae?
    • Gram-negative, rod shaped
    • fecal-oral transmission
    • greatest reservoir is humans
    • affects mostly age 1-5
    • invades host cells.
  12. What is a complication of shigellosis?
    HUS: Hemolytic-uremic syndrome.
  13. What do campylobacter bacteria look like?
    Motile and curves S-shape, or spiral rod.
  14. What are some clinical features of Yersinia enterocolitica?
    • fever, diarrhea, abdominal pain (RLQ)
    • Rectal bleeding, ileum perforation
    • Reactive polyarthritis
    • Erythema nodosum
    • Exudative pharyngitis.
  15. What are three characteristics of Yersinia enterocolitica?
    Gram negative, Non-lactose fermenter (NLF), bacilli.
  16. What is the most common health-care associated diarrhea?
    Clostridium Difficile.
  17. What are three characteristics of C. difficile?
    • Gram + bacilli
    • Anaerobe
    • Spore Forming.
  18. What are the three reserviors for C. difficile?
    Soil, environment, colonized people.
  19. When does C. difficile infection usually occur?
    After course of broad-spectrum antibiotics (killing normal intestinal flora).
  20. What is a characteristic of its pathogenesis?
    Forms a pseudomembrane on the colon (pseudomembranous colitis - PMD).
  21. What is one severe complication of CDAD (C. difficile Associated Disease)?
    Toxic Megacolon.
  22. What are four diagnostic methods for C. difficile?
    • Cytotoxin assay
    • Immunoassay (ELISA) for toxin
    • Stool culture
    • PCR.
  23. What are the two toxins released by C. difficile?
    • Toxin A: enterotoxin, causes tissue damage, fluid secretion, inflammation (not necessary for virulence)
    • Cytotoxin B: 1000x more potent than A, activate release of cytotoxins from monocytes.
  24. What are some characteristics of CMV?
    • Largest genome of all herpes viruses (betaherpesvirus)
    • ubiquitous
    • most cases sub-clinical.
  25. What are some clinical features of CMV infection?
    • Mononucleosis-type syndrome
    • Interstitial pneumonia
    • Hepatitis
    • GBS
    • meningoencephalitis.
  26. What stain is used to visualize Cryptosporidium?
    Modified Kinyoun acid-fast stain -- red sphere.
  27. What are some clinical manifestations of Cryptosporidia infection?
    • Voluminous, watery diarrhea - without blood or leukocytes -- associated with cramps, fatigue, anorexia
    • Can be fulminant and rapidly fatal in HIV or immunocompromised patients.
  28. What can infect that is found in raspberries?
    Cyclospora.
  29. What stain is used to visualize cyclospora?
    • Acid Fast
    • Should be done several times - low excretion.
  30. What is a characteristic of Microsopidiosis?
    Caused by 6 different genera of obligate intracellular, monocellular parasites.
  31. What stain is used in the stool examination to diagnose microsopidiosis?
    Weber's chromatrope-based stain.
  32. Name two liver flukes?
    • Clonorchiasis
    • Opisthorchiasis.
  33. How do you diagnose liver flukes?
    • Ultrasound of liver
    • Examination of stools for eggs.
  34. In who do most cases of spontaneous bacterial peritonitis present?
    Patients with ascites from chronic liver disease.
Author
arimoses
ID
39166
Card Set
GI infections.txt
Description
GI infections
Updated