medstu2006

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I have a Micro NBME tom. I really cannot figure out a way to distinguish the cause of pneumonia based purely on symptoms. A lot of times the question stem will only provide the symptoms and may be ab X-ray description, but nothing else.
How does a viral pneumonia present differently than a bacterial pneumonia? Any kind of help would be appreciated.
 

meningioma

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Viral pneumonia has less or no fever while bacterial pneumonia has a high grade fever.

viral pneumonia insidious in onset.

viral pneumonia is interstitial pneumonia so no signs of consolidation. also not much of sputum production for the same reason.

viral pneumonia has mononuclear infiltrates while bacterial pneumonia has neutrophilic infiltrates.

Most common viral pneumonia s RSV. Most common bacterial pneumonia s Strep. pneumoniae.

tat s all the main differences between them!!
 

agranulocytosis

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Viral pneumonia has less or no fever while bacterial pneumonia has a high grade fever.

viral pneumonia insidious in onset.

viral pneumonia is interstitial pneumonia so no signs of consolidation. also not much of sputum production for the same reason.

viral pneumonia has mononuclear infiltrates while bacterial pneumonia has neutrophilic infiltrates.

Most common viral pneumonia s RSV. Most common bacterial pneumonia s Strep. pneumoniae.

tat s all the main differences between them!!
Mycobacteria pneumonia can also be insidious with low grade fever. But for all intents and purposes, I would agree with your generalizations.
 

Mediculous

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Agranulocytosis,
I would associate Mycoplasma pneumonia with insidious onset and low grade fever, just like the viral pneumonias. I would associate Mycobacteria tuberculosis with hemoptysis, fever, chills, fatigue, weight loss, and night sweats; Mycobacterium avium complex with TB like symptoms in an AIDS pt with diarrhea.
 

agranulocytosis

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Agranulocytosis,
I would associate Mycoplasma pneumonia with insidious onset and low grade fever, just like the viral pneumonias. I would associate Mycobacteria tuberculosis with hemoptysis, fever, chills, fatigue, weight loss, and night sweats; Mycobacterium avium complex with TB like symptoms in an AIDS pt with diarrhea.
Yeah, you're right. Sorry about the gaffe. In my mind I was going the direction of atypical pneumonia. It happens to me a lot with these two genera because of the similar prefix "Myco". :oops:
 

docmd2010

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Also, just to confuse you a little more:

Bacterial pneumonia-typically is typical, i.e. it produces sputum

Viral-atypical, very little sputum, i.e. dry cough...


Of course there are some exceptions to this rule,
Legionella, mycoplasma, and chylamydia (i can never spell this one) cause ATYPICAL pneumonia.

Kleb-the red-jelly like sputum, look for the alcoholic

Mycoplasma-the most common cause of pneumonia in a young adult

Legionella-air conditioners, and contaminated water systems, also the typical patient with legionella will have COPD, will also have GI symptoms such as diarrhea in addition to his/her pneumonia.

Strep pneumo-produces the typical "rusty" colored sputum
 
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medstu2006

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Also, just to confuse you a little more:

Bacterial pneumonia-typically is typical, i.e. it produces sputum

Viral-atypical, very little sputum, i.e. dry cough...


Of course there are some exceptions to this rule,
Legionella, mycoplasma, and chylamydia (i can never spell this one) cause ATYPICAL pneumonia.

Kleb-the red-jelly like sputum, look for the alcoholic

Mycoplasma-the most common cause of pneumonia in a young adult

Legionella-air conditioners, and contaminated water systems, also the typical patient with legionella will have COPD, will also have GI symptoms such as diarrhea in addition to his/her pneumonia.

Strep pneumo-produces the typical "rusty" colored sputum
Thanks. Also, Pseudomonas aeruginosa causes pneumonia in patients with CF.

Thanks everyone. This helps a lot.
 
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medstu2006

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Viral pneumonia has less or no fever while bacterial pneumonia has a high grade fever.

viral pneumonia insidious in onset.

viral pneumonia is interstitial pneumonia so no signs of consolidation. also not much of sputum production for the same reason.

viral pneumonia has mononuclear infiltrates while bacterial pneumonia has neutrophilic infiltrates.

Most common viral pneumonia s RSV. Most common bacterial pneumonia s Strep. pneumoniae.

tat s all the main differences between them!!
Thanks for the pointing out the differences.
I'm not sure what you mean by viruses causing interstitial pneumonia. Isn't pneumonia excess edema in the interstitium and the alveolar spaces? So are you implying that in a viral pneumonia there is no excess fluid in the alveolar space, but only in the interstitium?
 

Fuzuli

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Thanks for the pointing out the differences.
I'm not sure what you mean by viruses causing interstitial pneumonia. Isn't pneumonia excess edema in the interstitium and the alveolar spaces? So are you implying that in a viral pneumonia there is no excess fluid in the alveolar space, but only in the interstitium?
Pneumonia is, by definition, the inflammation of the parenchmya of the lung, which includes alveoli and surrounding interstitium. According the the localization, pneumonias are classified into 3 categories:

1) Lobar pneumonia: This type classically involves an entire lung lobe. There are four stages of lobar pneumonia: Congestion, which occurs typically during the first 24 hours, is characterized by alveolar edema. Many bacteria are present in this fluid, but relatively few PNLs. Fine crackles can be heard at this stage.
Second stage, red hepatization, is characterized the presence of erythrocytes, PNLs and fibrin within the alveoli. During this stage, characteristic bronchial sounds can be heard.
Gray hepatization is the third stage and is characterized by progressive disintegration of the erythrocytes mentioned above. Due to this process, hemosiderin is produced. There are many PNLs and relatively few bacteria within the alveoli.
Final stage is resolution and it's characterized by digestion of the fibrino-purulent exudate within the alveoli.

2) Lobular pneumonia (= Bronchopneumonia): This is defined as the patchy infiltration of one or more lobes. Exudate is mainly located in bronchi and bronchioles, and it passes to the adjacent alveoli by centrifugal force.

3) Interstital pneumonia: This type mainly involves the interstitium. Exudate is mainly located within the alveolar septa. Alveoli themselves do not contain a significant amount of exudate.

Hope this helps.