-
How do Fungi and Molds differ from bacteria?
- Cell wall is different
- Mostly aerobic
- Reproduce by budding, not mating
- Do not produce exo/endotoxins
-
What is the response of the body after exposure to fungi?
Formation of a granuloma
-
Explain the granuloma formation
- After phagocytosis by macrophages, yest replicates 15-18 hrs
- As host immunity response develops, yeast growth ceases 1-2 weeks exposure
- Delayed-type hypersensitivity to histoplasma entigens 3-6 weeks
- Over weeks to months, inflammatory resonse produces calcified fibrinous granulomas with areas of caseous necrosis
-
Why is candida albicans considered an opportunistic yeast infection?
Because it is in the normal flora of many health people.
-
Where does candida albicans reside in the human body?
skin, GI tract, MouthVagina
-
What type of environment does a fungus need to survive?
High pH, Antibiotics, skin invasion with warm, moist areas, (think skin folds)
-
What is the term used to describe amebas, sporazoans, flagellates, cillates?
Protazoa
-
What is the term used to describe Flatworms and round worms?
Helminthes
-
What are two common intestinal protozoas?
-
What is the mode of transmission for amebic dysentery
Unwashed fruit and vegetables
-
What are symptoms of amebic dysentery?
- Bloody mucous diarrhea
- abdominal pain
- Flatulence
- Tenesmus (painful defecation)
-
Describe the pathogensis of amebic dysentery
- Invade colon epithelium
- secrete enzymes that leds to localized necrosis
- Progress into submucosa
- Reach portal circulation and leads to liver abscess
-
Describe the mode of transmission for Giardia
Fecal contaminated water
-
Describe pathogenesis of Giardia
- Ingested, but does not invade
- Leads to protein and fat malabsorption
- Has flagella and suction disk that causes local inflammation.
-
What are the symptoms of Giardia
Nonbloody, foul smelling diarrhea
-
How many days can Clostridium difficile live on a surface?
40 days
-
Where is Clostridium difficile found?
Hospital - on bedrails, windowsills, floors, toilets, our hands
-
What are risk factors for C diff?
- Advanced age
- Antibiotic therapy - 2 or more
- Immunosuppressive therapy
- Nasogastric tube
- Use of antacids/proton pump inhibitors
- Prolonged hospital stay
- Recent surgical procedure
- Sharing hospital room with c diff infected patient.
-
Describe pathophysiology of C Diff
- 1) imbalance of normal bacteria flora of colon
- 2)organism produces exotoxins in intestinal lumen
- * Toxin A activates macrophages and mast cells which inflame colon
- * Toxin B destroys the colon wall
-
What are the findings on presentation for C diff?
- Begin 4-9 days on antibiotics, can begin up to 8 weeks after
- Focal ulcerations on the colon wall
- Elevated WBC (>15,000)
-
What is the treatment for C Diff?
- Stop offending antibiotic
- Metronidazole (90% response rate)
- Fluid/electrolyte replacement
- Vancomycin (oral, because IV does not reach the gut)
- Questran binds to toxins
- Probiotics
|
|
