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36 Cards in this Set
- Front
- Back
Drugs |
Metronidazole, clindamycin, fidaxomicin, chloramphenicol (rare in US) |
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Metronidazole |
metabolized inside anaerobic bacteria, damages bacterial DNA IV and PO forms; can penetrate CNS most effective against Gm- anaerobes, Clostridia spp., Gardnerella vaginalis, Helicobacter pylori |
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Metronidazole S/E |
nausea, diarrhea, metallic taste, seizures, peripheral neuropathy, disulfiram-like rxn with alcohol |
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Metronidazole indications |
anaerobic infections, AB-associated colitis, bacterial vaginosis, H. pylori peptic ulcers |
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Clindamycin |
binds to 50s ribosomal subunit, facilitates opsonization, phagocytosis, intracellular killing IV and PO forms, does NOT penetrate CNS |
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Clindamycin activity |
most anaerobes outside CNS, increased resistance among Bacteroides fragilis most aerobic Gm+ (pneumococci, strep, MSSAs, some CA-MRSA) |
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Clindamycin S/E |
AB-associated diarrhea due to Clostridium difficile; anorexia, N/V; neutropenia and thrombocytopenia rare |
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Chloramphenicol |
binds to 50s subunit; active vs. most anaerobes and several aerobes severe s/e: aplastic anemia and neonatal toxicity (Grey baby syndrome), effective for some rickettsial diseases |
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O2 and anaerobes |
anaerobes don't have superoxide dismutase (can't break down superoxide) |
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Anaerobic infections |
causes: breakdown of normal mucosal barrier (poor blood supply, trauma, tissue destruction, necrosis) many species normally involved |
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Clostridium species |
spore-forming, gram-positive rods "box cars" in soil and animal intestines release protein toxins, some invade tissues to cause wounds and abscesses |
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Clostridium botulinum |
heat-resistant spores release neurotoxin types A-G that prevent release of NT acetylcholine |
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Food-borne botulism |
flaccid paralysis 12-36 h post-ingestion; CNs affected first (diplopia, blurred vision, swallowing difficulty) descending paralysis, death from resp. failure |
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Infant botulism |
Rare, large intestine colonized w/ slow absorption of toxin hypotonia, weak cry and suck reflex |
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Wound botulism |
rare, toxins produced at wound site and absorbed into tissues |
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Clostridium tetani |
Tetanospasmin = major toxin that inhibits NT release and normal inhibitory input causing spastic paralysis; lock jaw followed by descending disease Rx: antitoxin, pen G, wound care, support Prevent: tetanus toxoid vaccine |
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Clostridium perfringens |
Food poisoning: meat poorly cooked then re-warmed; enterotoxin produced that acts as a superAg in GI tract - watery diarrhea, crampy ab pain Gas gangrene: lecithinase alpha-toxin damages cell membranes; wound pain, discoloration, crepitation, myonecrosis |
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Clostridium difficile infection |
dormant in large bowel; normal GI flora suppressed by AB but resistance allows overgrowth, secretion of exotoxins toxins inactive Rho family of guanosine TPs |
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Clostridium difficile: epidemiology |
toxinotype III BI/NAP1/027 strain - mortality rates 3X those of less virulent strains |
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C. difficile risk factors |
AB use: ampicillin, amoxicillin, cephalosporins, clindamycin old age, IBD, organ transplant, chemo, CKD, immunodeficiency |
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C. difficile clinical manifestations |
mild: afebrile, mild abd. pain, labs OK moderate: non-bloody diarrhea, mod. abd pain, nausea w/ occasional vomiting, dehydration severe: severe or bloody diarrhea, pseudomembranous colitis, severe abd. pain, tenderness, vomiting complicated: toxic megacolon, perotinitis, resp. distress, hemodynamic instability |
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Clostridium difficile Rx |
Mild: Metronidazole po Moderate: Metronidazole po, vancomycin po Severe: hospitalization, vancomycin, metronidazole IV |
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C. difficlile-assoc. diarrhea therapy |
Fidaxomicin: macrocyclic AB that inhibits protein synthesis not active against Gm- anaerobes or aerobes (gut flora) |
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Gram-positive anaerobic cocci |
pepto-, strepto-, peptrostreptococcus normal: mouth, skin, GI tract, vagina infections: aspiration pneumonia, surgical wounds, intraabdominal, female pelvic |
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Gram-negative anaerobic cocci |
Veillonella normal: mouth, vagina infections: human bite wounds, PID |
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Anaerobic cocci Rx |
penicillins, metronidazole, clindamycin |
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Bacteroides fragilis |
non-sporulating Gm-neg. bacillus forms abcesses, bacteremia normal colon flora infections: intraabdominal inf., pelvic, decubitus ulcers, diabetic foot ulcers |
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Bacteroides fragilis Rx |
metronidazole, beta-lactam/beta-lactamase inhibitor combinations, carbapenems |
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Prevotella |
non-sporulating anaerobe, Gm- oropharynx, GI and GU tracts mouth, lung, intraabdominal infections |
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Fusobacteria |
non-sporulating anaerobe, Gm- oropharynx, GI and GU tracts sinusitis, chronic otitis, dental, can cause brain abscess |
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Propionibacterium acnes |
non-sporulating anaerobe, Gm+ skin flora, causes acne |
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Actinomyces |
aerobe that grows best anaerobically; filamentous, branching, Gm+ infections: head/neck, chest and abdomen, draining sinuses Rx: high dose Pen G |
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Head & neck infections |
Fusobacterium, Prevotella, Gm-pos. cocci Infections: dental, chronic sinusitis, chronic otitis, brain abscesses |
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Pleuropulmonary infections |
Fusobacterium, Prevotella, Gm-pos. cocci Infections: pneumonia with lung abscess cavity, empyema |
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Intraabdominal infections |
Bacteroides, Clostridium, Fusobacterium, Gram-positive cocci, aerobes infections: abscesses and/or peritonitis |
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OB-GYN infections |
Bacteroides, Gm-pos. cocci, Clostridium infections: tubo-ovarian abscess, pelvic abscess, septic abortion, endometritis, post-op |