N4B1Q23 Otitis

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N4B1Q23 Otitis

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Cedrick
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06/19/06 - 09:36 PM

A 3 year old girl is brought to the physician because of fever and pain in her right ear for 8 hrs.
Examination of the right ear shows perforation of the tympanic membrane and purulent exudate
A Gram stain of the exudate shows gram positive diplococci
which of the following is the most likely causal organism ?

a.-Haemophilus influenzae
b.-Moraxella catarrhalis
c.-neisseria meningitidis
d.-staphylococcus aureus
e.-streptococcus pneumoniae

sticking out tongue

bactitech
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06/19/06 - 10:31 PM

a. This is a pleomorphic gram negative rod - so it's NOT H. influenzae.

b. This is a gram negative diplococcus - more like a coccobacillus - so it's NOT M. catarrhalis

c. This is also a gram negative diploccoccus - so it's NOT N. meningitidis

d. This is gram positive cocci in clusters - so it's NOT S. aureus

e. This IS a gram positive diplococcus/cocci in pairs - so it IS S. pneumoniae.

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Cedrick
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06/19/06 - 10:32 PM

I think so too !!!

robin082006
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06/19/06 - 11:12 PM

E

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mjl1717
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06/20/06 - 06:02 AM

bactitech wrote:
a. This is a pleomorphic gram negative rod - so it's NOT H. influenzae.

b. This is a gram negative diplococcus - more like a coccobacillus - so it's NOT M. catarrhalis

c. This is also a gram negative diploccoccus - so it's NOT N. meningitidis

d. This is gram positive cocci in clusters - so it's NOT S. aureus

e. This IS a gram positive diplococcus/cocci in pairs - so it IS S. pneumoniae.

bactitech -thank you for the insight on each bateria

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sugandhna
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07/03/06 - 03:44 AM

e is the answer

klimt
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10/01/06 - 10:07 AM

E

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jsknetsdude
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10/08/06 - 02:07 PM

e.-streptococcus pneumoniae

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