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Old 10-01-2012
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Bacteria Which microorganism caused this lobar pneumonia

A 72-year-oldman becomes ill with a fever, cough, and myalgia during the winter. Over the following days, he begins to feel slightly better. However, he wakes up one morning with fever, chills, worsening malaise, dyspnea, and a new productive cough. A complete blood count reveals a WBC count of 16,000/mm≥, a 80% predominance of neutrophils, and a left shift with 12% band forms. X-ray of the chest reveals lobar pneumonia.
The infections is due to which organism?

a) Streptococcus pneumoniae
b) chlamydophila pneumoniae
c) staphylococcus aureus
d) Legionella pneumophila
e) Haemophilus influenza.
f) moraxella cattarhalis
g) mycoplasma pneumoniae
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Old 10-01-2012
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a) Streptococcus pneumoniae

bacterial pneumonia secondary to the flu?
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Old 10-01-2012
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staphylococcus aureus is most common after viral pneumonia. 2nd most common is Hib
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Old 10-01-2012
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Quote:
Originally Posted by beka-CTS View Post
staphylococcus aureus is most common after viral pneumonia. 2nd most common is Hib
yup, you are right thanks for reminding me!

S. aureus it is
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Quote:
Originally Posted by Casandra View Post
yup, you are right thanks for reminding me!

S. aureus it is
You're welcome. Today i going through gram + ones and
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Old 10-01-2012
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Will go with C..
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My answer is C) Staph aureus, because it is the most common cause of bacterial lobar pneumonia following influenza, usually causing a necrotiseing pneumonia.
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Quote:
Originally Posted by venky2600 View Post
A 72-year-oldman becomes ill with a fever, cough, and myalgia during the winter. Over the following days, he begins to feel slightly better. However, he wakes up one morning with fever, chills, worsening malaise, dyspnea, and a new productive cough. A complete blood count reveals a WBC count of 16,000/mm≥, a 80% predominance of neutrophils, and a left shift with 12% band forms. X-ray of the chest reveals lobar pneumonia.
The infections is due to which organism?

a) Streptococcus pneumoniae
b) chlamydophila pneumoniae
c) staphylococcus aureus
d) Legionella pneumophila
e) Haemophilus influenza.
f) moraxella cattarhalis
g) mycoplasma pneumoniae
a.
scenario looks like post flu.. and staph aureus i think is superimposed on flu patients. But since more than 90 percent cases of lobar pneumonia is due to strept pneumonia will go with a.( Robbins 7th edition page 479)
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Correct Answer c is right

the correct answer is C) staphylococccus aureus...

staphylococcus aureus is the most common bacterial infection causing pneumonia post viral infections(followed by hemophilus pneumoniae)

here the pt. had already suffered several flu symptoms in winter and as no medications or full recovery has been specified.....staphylococcus aureus is the most appropriate to pick here.....
ya streptococcus pneumoniae(rusty sputum) is the most common bacteria causing pneumonia above 60 yrs age...but as prior flu infection is clearly specified..staph is the right one..

and important to remember more of staph pneumoniae....it causes salmon colored sputum with pneumatocysts/coeles(bacteria causing cysts in lung)
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