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Old 07-06-2011
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Question rusty nail ??pseudomonas or C.perfringens

stepped on a big rusty nail i remember from step 1 that pseudomonas osteomyelitis very common

in kaplan surgery now similar story but they said gas gangrene (C.Perfringens )

so the clue rusty nail apply to both ??

how to differentiate between both ??
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Old 07-06-2011
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Post both

  • Pseudomonas
  • aerobes, occurs on skin surface
  • opportunistic pathogen
  • may cause serious & lethal infection
  • colonize ventilators, iv catheters, urinary catheters
  • Wound infection, burn, septicemia
  • Treatment: aminoglycosides, piperacillin, ceftazidime
<LI sizset="0" sizcache="6478">
  2. Cl. Perfringens, Cl. Septicum
  • Exotoxins: lecithinase, collagenase, hyaluridase
  • Large wounds of muscle ( contaminated by soil, foreign body )
  • Rapid myonecrosis, crepitus in subcutaneous tissue
  • Seropurulent discharge, foul smell, swollen
  • Toxemia, tachycardia, ill looking
  • X-ray: gas in muscle and under skin
  • treatment:Penicillin, clindamycin, metronidazole
  • Wound exposure, debridement , drainage, amputation
  • Hyperbaric oxygen
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Old 04-26-2012
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The clue is the presentation: soft tissue infection or osteomyelitis?

Pseudomonas is notorious for osteomyelitis following nail puncture in adults, while clostridium hardly if ever causes osteomyelitis.

C perfringes (an anaerobe) on the other hand, causes subcut infection and release O2 in the process, thus the gas gangrene (subcut crepitus).
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Old 04-27-2012
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Another point is that you get Pseudomonas infection if the nail goes through sneakers since sneakers contains the Pseudomonas reservoir. So, the organism is not in the nail (nail can be clean & not rusty) but you get inoculated by Pseudomonas from the shoe sole.
In contrast, the clostridium is in the nail (rusty,dirty, dusty) and you can be barefoot to get inoculated.
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