3 bacteria needed to know

Question 0

C. difficile

Answer 0

mostly acquired nosocomically (hospital)
- a normal flora in 3% of healthy adults
-strict anaerobe
-Gram + bacillus
-spore forming that can survive for months
-has endotoxins A and B cause damage to intestine mucosa
A- enterotoxin ( fluid), diarrhea
B-cytotoxin ( pus)- cell death
- dehydration and AAC
-treatment includes antibiotics, probiotics, fecal implants

Question 1

Neisseria meningitidis ( menigococcus)

Answer 1

• inflammation of the meninges, caused by microorganism infecting CSF
• Gram - diplococcus, capsule
• has 12 sterotypes based on capsule carbohydrates
• only 4 subtypes responsible for epidemics (A,B,C, W-135)
• A: Africa
• B: Americas
• C: alberta one

Question 2

Listeria monocytogenes

Answer 2

• gram + bacillus, non-spore forming
• facultatively anaerobic
• motile flagella
• grows well on blood algar plate-sheep blood, wide temp range, pH range, high concentration of NaCl
• usually in nature, soil, animal intestine through contaminated feed
• animals: CNS infection, septic abortion
• humans: food borne disease, meningitis, miscarriage
• ingestion of contaminated food, invasion through gastric epithelial barrier, grows in macrophages ( giant WBC)