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A 5-year-old boy returns from summer camp with several minor cuts and abrasions on legs. He has fever and extensive cellulitis, subcutaneous tissue and muscles are involved. Necrotic tissues were surgically reomoved and broad spectrum antibiotics were used. Which of the following microorganisms usually causes necrotizing fasciitis?

  • a. bacillus cereus
  • b. clostridium tetani
  • c. A-group streptococci
  • d. Micrococcus sp.
  • e. Staphylococcus aureus

It is so severe that I started think that Staphylococcus aureus is possible. My previous answer was A-group streptococci, but I disagree with it now.

What is causing the case?

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if broad spectrum are being given chances are that it will be staph aureus because nowadays resistance to multiple antibiotics is being found in it. – biogirl Aug 25 '13 at 16:15
@biogirl broad spectrum antibiotics are the standard first step in treating just about any infection. – terdon Aug 25 '13 at 16:19
@terdon You are right.I just thought that because the question specifically states "broad spectrum" it may hint at staph aureus.I may be wrong. – biogirl Aug 25 '13 at 16:22
At the moment, I am not sure what is the right answer. I am wondering still between C and E. – Masi Aug 25 '13 at 16:25
It is not mentioned in the question about the time period, how long it took that the surgeon was done from the incident. If it was done very fast after incident, then I would pick Staphylococcus aureus. However, I do not understand its pathology yet. – Masi Aug 25 '13 at 16:26
up vote 1 down vote accepted

Staphylococcal infection is more likely to cause abscesses and Streptococcal infection is more likely to cause cellulitis. It is not clear how a 5 year old did not get medical attantion till he got to this serious state. Why was culture not done? Surgical removal of necrotic tissue due to cut and bruises? doesn't tally with cellulitis. Incision and drainage is a standard proceedure for absecesses, is that what was done? Is this a hypothetical question?

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I do not know. I hope it is. – Masi Aug 25 '13 at 18:26

No. It is caused by A-group streptococci. Source Murray and empirical evidence.

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