Clostridium difficile: Gram positive
1. Spore producing
- Need to wash with soap and water for spores
2. Affects nocosomial patients: diarrhea
- From patient to patient
- Antibiotics lower to intestinal flora: specially 3.Clindamycin
- 4. Not proper hand-washing
Toxins
- 5. Exotoxin A: Binds to 7.brush border and produces: inflammation, cell
death and 8. watery diarrhea
- 6. Exotoxin B: Disrupts cytoskeleton integrity by 9. depolymerizing
actin: enterocyte death and necrosis
- Yellowish exudate that forms 10. pseudomembrane that covers the
colonic mucosa: pseudomembranous colitis
Diagnostic
- Pseudomembrane: eg. with histo or PCR
- 11. Check in the stool for toxin
12. Obligate anaerobe
Treatments
- 13. Oral vancomycin
- 14. Metronidazole
Clostridium botulinum: Gram positive
1. Transmitted by improper canning of food: preformed toxins
Affects multiple family members
2. Spore forming
3. Obligate anaerobe
Travels through blood: unable to cross brain barrier
- Acts only at PNS
4. Causes flaccid paralysis: descending
5. Early symptoms: Ptsosis and diplopia, neck distentions
6. Works as clostridium tetani (protease) but different target cell
- 7. Attacks motor neurons releasing Acethly-coline: inhibits muscle
contraction
8. Causes Floppy Baby Syndrome: flaccid paralysis
- Babies have lower intestinal flora
- 9. Transmitted usually ingestion of honey (contains many spores)
- Adults get only in preformed toxins
Clostridium tetani
Gram positive
1. Obligate anaerobe
2. Spore forming
- In 3. Rusty nails
- in 4. Soil
Symptoms
- 3. Risus sardonicus or Lock Jaw
- 4. Opisthotonus: exaggerated arching of back
Pathology:
- After puncture--> spores stay in wound site--> tetanus toxin-->
5. travels retrograde through nerves--> 6. Cleaves SNARE protein -->
7. Inhibition of release of GABA and Glycine of Renshaw cells
8. Toxoid vaccine
- Protein with toxin which induces immune response against the toxin
Bacillus anthracis
1. Black eschar: necrosis
2. Erythematous ring
3. Large gram positive bacilli in chains
4. They're encapsulated
- 5. Made up of protein: 6. Poly-D-Glu
7. Obligate aerobe
8. Spore forming
Toxins
- 9. Edema Factor (EF): works as adenylase cyclase: 10. increase cAMP IC--
> increase EC fluid--> Edema--> Lower defenses--> Lower phagocytosis
- 11. Lethal factor (LF): exotoxin that acts like a protease and cleaves 12. MAP
kinase (cell growth)--> Tissue necrosis
13. Causes Wool sorter's disease
Pulmonary antrhax: starts with no specific symptoms--> then move to mediastinal
LN --> 14. Hemorrhagic mediastinitis and pulmonary hemorrhage-->
15. Widened mediastinum--> almost 100% mortality
Treatment:
- 16. Fluoroquinolones
- 17. Doxycycline
18. Bacillus Cereus: food poisoning
Enterococcus
1. Faecalis: more common
2. Faecium: less common but more serious
3. It can grow in 6,5% NaCl
4 Bile resistant
Causes
- 5. Biliary tree infections
- 6. Endocartidits
- 7. UTI's
8. Vancomycin resistant (specially Faecium)
9. Linezoid is used for treatment
- Very expensive and effective
- 10. Or Tigecycline
Both 9. Sickle cell disease (Asplenia) are
1. Alpha hemolytic: partial hemolysis more susceptible to encapsulated
- Green organisms
Streptococcus pneumoniae 10. Macrolides susceptible
2. Polysaccharide capsule - 11. Also suceptible to 3rd generation
- Major virulence factor cephalosporins: ceftriaxone
3. Optochin sensitive Pneumococcal vaccines
4. Lancet-Shaped diplococci - 12. Adults: without protein-->IgM: not
5. Bile soluble that good
6. Causes lobar pneumonia - 13. Children: conjugated with protein--
- "Rust-colored" sputum > IgG: Good
- At lower lobes Streptococcus Viridans
7. Causes MOPS: Nr 1 cause 14. Unencapsulated
- Meningitis 15. Optochin resistant
- Otitis media 16. Bile insoluble
- Pneumonia 17. Strep mutans causes dental caries
- Sinusitis 18. Causes Subacute endocarditis in
8. Ig A protease: colozines mucosa damaged valves
- Specially mitral
- 19. Adheres to platelets using
20. Dextrans
