Bugs - Anaerobes Flashcards
peptostreptococcus is found where?
what diseases does it cause?
mucosal surfaces AND skin
Causes:
- sinusitits(can travel to brain, lungs)
- intraabdominal infections
- endometritis, pelvic abcesses
- cellulitis, nec fasc
- osteomyelitis
as an anaerobe, this will create abcesses
morphology of peptostreptococcus
GP cocci; anaerobe
name the relavent anaerobic, GP, non-spore, rods
actinomyces
lactobacillus
mobiluncus
propriobacterium
what diseases are caused by actinomyces?
actinomycoses:
- cerebral
- cervicofacial(angle of mandible)
- thoracic - can cause aspirate pneumonias; can move through lungs to make draining lesion
- abdominal - appendicitis can perforate, cause bacteremia and allow lesions in liver
- pelvic
causes woody, sulfur granules in its abcesses
has a molar tooth appearance upon culture
actinomyces israelii
pathogenesis of actinomyces israelii
pt’s mucosal barrier is disrupted, allowing the actinomycoses to travel
surgery, trauma, radiation, aspiration, foreign body, diverticulitis, appendicitis
treatment for actinomyces
prolonged penicillin
surgical debridement
can use erythromycin, clindamycin too
lactobacillus diseases?
type of pt infected?
treatment?
sepsis, and endocarditis(if previous valve problems)
pts are immunocompromised
treat with penicillin/gentamicin
what disease is mobiluncus associated with
what is the treatment for this disease
bacterial vaginosis
metronidazole; however, note that mobiluncus is resistant to metronidazole
vats dis
mobiluncus
comma shaped, GP non-spore, anaerobic rod
propionibacteria is responsible for what diseases?
- acne
- opportunistic diseases via foreign bodies
- prosthetic heart valves
- prosthetic joints
- vascular catheters
vats dat
clumped GP, nonspore anaerobic rods
propionibacteria!
treament for:
- actinomyces
- lactobacilli
- mobiluncus
- propionibacteria
- *actinomyces** - penicillin; erythromycin, clindamycin
- *lactobacilli** - penicillin, or combo; resistant to vanc
- *mobiluncus** - resistant to metronidazole but still used to treat bacterial vaginosis
- *propionibacteria** - benzoyl peroxide, penicillin, tetracyclines, erythromycin, clindamycin
bacteroides fragilis morphology
anaerobic GN rod
LPS w/out endotoxin activity
has an important anti-phagocytosis capsule; stimulates abcess formation
bacteroides fragilis cause what infecitons?
characterized by abcess formation
intraabdominal
pelvic/endometritis
surgical wound infections
skin/soft tissue infections after surgery/trauma
bacteroides fragilis is resistant to….
what should you treat with?
penicillins
metronidazole and antibiotics to cover other bugs in infection
fusobacterium nucleatum causes infections where?
oropharynx
think gingivitis to pharyngitis to jugular venous thrombophlebitis
these infections are dangerous; can move up and down in parapharyngeal spaces(DANGER ZONE)
Lemierre’s Syndrome
phayngitis is complicated by peritonsillar abscess
spreads through parapharyngeal spaces to the internal jugular vein
causes thrombophlebitis which can embolize and spread to lungs where it forms MORE ABCESSES!
treatment for fusobacterium nucleatum
b-lactam+/-b-lactamase inhibitor
debride abcess!
clostridium tetani
pathogenesis
manifestation
introduced to body via dirty nail, splinter, dirty needle
mediated by tetanus toxin(A/B peptides); a-peptide inhibits GABA/glycine which are inhibitory NTs; causes SPASTIC PARALYSIS
type of clostridium tetani manifestation
- generalized - masseter cntrcn; opisthotonos(back cntrcn); airway can become compromised from constant thoracic cntrcrn
- localized - limited to site of inoculation; can develop into general
- cephalic: injury to head/neck, in developing coutnries; characterized by cranial nerve involvement
- neonatal: umbilical stump exposed to clay/dung
treatment for c. tetani
clean wound
metronidazole
passive immunization w/tetanus immunoglob
clostridium botulinum
how does it manifest?
what are the 3 forms?
botulinum toxin, prtctd in GI, blocks neurotransmission at peripheral cholinergic synapses; inactivates proteins that release ACh
FLACCID PARALYSIS
- foodborne - toxin is found in food
- wound - organism contaminates wound; multiplies; makes toxin
- infant - organism is ingested w/food; multiplies in GI, maks toxin
clinical presentation of c. botulinum
cranial neuropathies w/symmetric descending paralysis
treatment of c. botulism
ventilatory support
metronidazole
trivalent botulinum antitoxin
most common forms of botulinum toxin in US
where is c. botulinum found?
toxins A, B, E
found on soil, surface of fruit/veggies, marine sediment
clostridium perfringens unique microbiology
large rectangular rods and “double zone” of hemolysis
rarely makes spores; aerotolerant; grows in culture fast
diseases caused by c. perfringens
- food poisoning: ab cramps; watery diarrhea; from contaminated meat products; heat-labile enterotoxin
- soft tissue infections: cellulitis, fasciitis, myonecrosis(gas gangrene); DANGEROUS; hemorrhagic bullae, severe pain, edema, pallor, subq emphysema; microscopy helpful!
- bacteremia: most blood isolates are useless
treatment for c. perfringens
penicillin works; use w/clindamycin (inhibits toxin synthesis)
toxins of c. diff
- enterotoxin(toxin A) - attracts PMN and makes them release cytokines
- cytotoxin(toxin B) - destroys cellular cytoskeleton of colon(destroy actin)
manifestation of c. diff
ranges from anti-biotic diarrhea to life-threatening pseudomembranous colitis
treatment of c. diff
discontinue any implicated antibiotics
give oral metronidazole, (oral vanc if bad)
disinfect room
STOOL TRANSPLANT
