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  #1  
Old 10-23-2012
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Question Gram-negative rods that ferment lactose

A patient in the hospital develops pleuritic chest pain, shortness of breath, fever, chills, productive cough, and colored sputum after 3 days of being in the hospital for major surgery. Physical examination shows tenderness to palpation without any areas of increased tactile fremitus. Blood and sputum cultures confirm gram-negative rods that ferment lactose, have a large mucoid capsule, and form viscous colonies. The patient subsequently dies from her infection. Which of the following is most likely to be found at autopsy?

A Acute inflammatory infiltrates from bronchioles into adjacent alveoli
B Congestion, red hepatization, gray hepatization, and resolution
C Diffuse, patchy inflammation localized to the alveolar wall interstitium
D Intra-alveolar hyaline membranes without alveolar space exudates
E Predominantly intra-alveolar exudate resulting in consolidation

this one is tough i guess
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Old 10-23-2012
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ya confuscious options

diagnosis is klebsiella pneumonia...

D (ARDS) is not for sure,........

B is full of disease pathophysiology of pneumonia....

so either A or E,C...

will go with C) Diffuse, patchy inflammation localized to the alveolar wall interstitium.....

ya remembered klebsiella cause atypical i think
thanks
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Old 10-23-2012
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me too D) Intra-alveolar hyaline membranes without alveolar space exudates
Klebsiella-----acute respiratory distress syndrom
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Old 10-23-2012
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Up's!My mistake !I think D)
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Old 10-23-2012
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I would choose A), because Klebsiella pneumoniae can cause bronchopneumonia.
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Quote:
Originally Posted by Teona View Post
I would choose A), because Klebsiella pneumoniae can cause bronchopneumonia.
yes,but i don't think that patient can die from bronchpneumonia
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Originally Posted by dr.Irina View Post
yes,but i don't think that patient can die from bronchpneumonia
but i never heard ARDS either leading from pneumonia....
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Old 10-23-2012
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if u read a question stem carefully which i didnt, most probably u answer it correctly
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Default my answer :)

I'll go with A Acute inflammatory infiltrates from bronchioles into adjacent alveoli

I excluded B) C) and E) bc the stem says: without any areas of increased tactile fremitus. So basically I excluded interstitium involvement.

That leaves me with A) and D). I excluded D) bc it says there are Intra-alveolar hyaline membranes without alveolar space exudates - I think in this patient the etiology is infectious so there would be an exudate.

I'm not sure though how to understand the "tenderness to palpation". Any ideas guys?
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Default Ards.......dd

DD...sepsis induced ARDS
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Quote:
Originally Posted by MedicalExaminer View Post
if u read a question stem carefully which i didnt, most probably u answer it correctly
i think i totally forgot abt the pneumonia and it's existence also after reading this question......need to revise again.......................

please post the answer...before the reader anxiety goes off....
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without any areas of increased tactile fremitus.

The correct answer is A. The characteristics of the microorganism indicate infection with Klebsiella species, while the physical exam points to a bronochopneumonia rather than a lobar pneumonia. K. pneumoniae is a gram-negative rod that ferments lactose and has a mucoid capsule. Bronchopneumonias are characterized by acute inflammatory infiltrates from bronchioles into adjacent alveoli. Pneumonia resulting from infection by this bacterium is often caused by aspiration, so that it is often seen in people with a loss of consciousness (ie, alcoholics). It is also more common in patients with diabetes.

Answer B is incorrect. Lobar pneumonia, most frequently due to Streptococcus pneumoniae, morphologically evolves through four stages without treatment: congestion, red hepatization, gray hepatization, and resolution. S. pneumoniae is an encapsulated gram-positive coccus. It is known for causing rust-colored sputum.

Answer C is incorrect. Interstitial pneumonias, from mycoplasma and viruses, are characterized by diffuse patchy inflammation localized to interstitial areas at alveolar walls.

Answer D is incorrect. Interstitial pneumonias, from mycoplasma and viruses, are characterized by diffuse patchy inflammation localized to interstitial areas at alveolar walls. They also have no exudates in alveolar spaces, but have intra-alveolar hyaline membranes.

Answer E is incorrect. Lobar pneumonia, most frequently due to Streptococcus pneumoniae, characteristically has predominantly intra-alveolar exudates, resulting in consolidation.
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Quote:
Originally Posted by MedicalExaminer View Post
without any areas of increased tactile fremitus.

The correct answer is A. The characteristics of the microorganism indicate infection with Klebsiella species, while the physical exam points to a bronochopneumonia rather than a lobar pneumonia. K. pneumoniae is a gram-negative rod that ferments lactose and has a mucoid capsule. Bronchopneumonias are characterized by acute inflammatory infiltrates from bronchioles into adjacent alveoli. Pneumonia resulting from infection by this bacterium is often caused by aspiration, so that it is often seen in people with a loss of consciousness (ie, alcoholics). It is also more common in patients with diabetes.

Answer B is incorrect. Lobar pneumonia, most frequently due to Streptococcus pneumoniae, morphologically evolves through four stages without treatment: congestion, red hepatization, gray hepatization, and resolution. S. pneumoniae is an encapsulated gram-positive coccus. It is known for causing rust-colored sputum.

Answer C is incorrect. Interstitial pneumonias, from mycoplasma and viruses, are characterized by diffuse patchy inflammation localized to interstitial areas at alveolar walls.

Answer D is incorrect. Interstitial pneumonias, from mycoplasma and viruses, are characterized by diffuse patchy inflammation localized to interstitial areas at alveolar walls. They also have no exudates in alveolar spaces, but have intra-alveolar hyaline membranes.

Answer E is incorrect. Lobar pneumonia, most frequently due to Streptococcus pneumoniae, characteristically has predominantly intra-alveolar exudates, resulting in consolidation.

thanks....so all the interstitial pneumonias will present with hyaline membrane formation...?
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i dont think so
hyaline membranes are itself the result of exudation of protein rich fluid and if theres no exudate there are no hyaline membranes

thats my assumption just
if anyone has contradictory proof pls share
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Quote:
Originally Posted by MedicalExaminer View Post
i dont think so
hyaline membranes are itself the result of exudation of protein rich fluid and if theres no exudate there are no hyaline membranes

thats my assumption just
if anyone has contradictory proof pls share
ok. actually i never heard of before that interstitial pneumonias causing hyaline membranes,so i thought of asking abt it from ur statement ..
..plz can you tell me the source of the question..?

thanks buddy
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First Aidô Q&A for the USMLE Step 1,
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nice q Thank you!
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