Infectious Diseases Flashcards
What diseases do anaerobic flora cause?
abcesses or peritonitis
When do anaerobic flora cause disease?
When they are introduced into normally sterile sites or when the balance of organisms is upset and pathogenic anaerobes overgrow
What diseases do environmental anaerobes cause?
tetanus
botulism
gas gangrene
What are the usual causes of abcesses?
commensal bacteria from adjacent sites
What do abcesses usually contain?
2 or 3 different species of mixed bacterial flora
What are the characteristics of anaerobic abcesses?
foul smelling
poorly circumscribed
pathologically resemble other pyrogenic infections
Where do anaerobic organisms grow?
where there is less oxygen and blood supply
What are Clostridial infections?
Gram positive bacillus anaerobes that produce spores in the soil
What does C. perfringens cause?
cellulitis myonecrosis of traumatic and surgical wounds uterine myonecrosis (illegal abortions) food poisoning gangrene
What does C. tetani cause?
tetanospasmin in puncture wounds and umbilical stump of newborn infants
What is tetanospasmin?
spasm of skeletal muscles (lockjaw)
What does C. botulism cause?
botulism
What is botulism?
flaccid paralysis of respiratory and skeletal muscles by blocking ACh release
Where does C. botulism grow?
in inadequately cooked foods as a neurotoxin
What does C. difficile cause?
pseudomembrane colitis
Where does C. diff grow?
overgrows other intestinal flora in antibiotic treated patients and releases toxins
What is clostridial gas gangrene?
life threatening
Characterized by marked edema and enzymatic necrosis of involved muscle cells 1-3 days after injury
What type of bacteria is Clostridium?
Anaerobe
What is Chlamydial trachomatis?
Gram negative Obligate Intracellular parasite
What is the most common sexually transmitted bacterial disease in the world?
Genital infection by C. trachomatis
What are the clinical features of Chlamydia?
epididymitis prostatitis pelvic inflammatory disease pharyngitis conjunctivitis perihepatic inflammation proctitis
What does chlamydia form?
Elementary bodies = inactive
Reticulate bodies = active
