White blood cell count - differentiating Viral from Bacterial infection

[HenrikFuture]

Can a white blood cell count differentiate a bacterial from a viral infection. Or maybe increase the likelihood of one over the other.

I have a belief that lymphocytes and monocytes may be related to viral infections. In truth i cannot remember who told me, and i have found it impossible to find any evidence of this on the internet.

If someone has a reference that explains characteristics of the "Bacterial infection" and "Viral infection" white blood cell count, that would be awesome.

Thank you

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[Psai]

Think it's bacterial - culture
think it's viral - pcr

 

[Doc2b_123]

Can a white blood cell count differentiate a bacterial from a viral infection. Or maybe increase the likelihood of one over the other.

I have a belief that lymphocytes and monocytes may be related to viral infections. In truth i cannot remember who told me, and i have found it impossible to find any evidence of this on the internet.

If someone has a reference that explains characteristics of the "Bacterial infection" and "Viral infection" white blood cell count, that would be awesome.

Thank you

One of our microbiology professors (DO program) also told us that an increase in neutrophils in sputum usually indicates bacterial infection, and increased lymphocytes usually indicates a viral infection. That's not super helpful, but you're not the only one that's heard that, at least.

 

[Shipping News]

These things are not specific at all. It's supposed to teach you a little bit about immunology and the response of the body to different kinds of infections but it's an oversimplification and not terribly helpful in practice. In the real world, you'll be culturing someone for bacterial infections in many bodily fluids if they have a fever. Those without a clear bacterial diagnosis will just be called sepsis and treated for their clinical syndrome. Most cases of pneumonia you're going to treat you'll never have a culture to confirm what bug it is.

For test purposes, if you see a WBC diff that shows tons of lymphocytes and monocytes, your gut should be a viral infection, an atypical bacterial infection, or an inflammatory disease.

 

[jqueb29]

I forget as far as in the blood itself, but I do know that in the CSF, elevated WBC high in PMNs indicates bacterial while elevated WBC high in lymphocytes suggests viral (or fungal).

 

[Low Flow]

I'll echo that we were told this as well. The professors basically said it's more of a pattern that should get you thinking viral vs bacterial, but not an absolute by any means, as mentioned above.

 

[Psai]

I forget as far as in the blood itself, but I do know that in the CSF, elevated WBC high in PMNs indicates bacterial while elevated WBC high in lymphocytes suggests viral (or fungal).

last time i checked, tb is a bacterium but what do i know

 

[beethousand]

last time i checked, tb is a bacterium but what do i know

Technically a mycobacterium to be pedantic.


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[Goro]

I just asked my Immunologist colleague about this and his two cents is that "lots of neutrophils = bacterial; lots of monos or lymphos = viral".

Can a white blood cell count differentiate a bacterial from a viral infection. Or maybe increase the likelihood of one over the other.

I have a belief that lymphocytes and monocytes may be related to viral infections. In truth i cannot remember who told me, and i have found it impossible to find any evidence of this on the internet.

If someone has a reference that explains characteristics of the "Bacterial infection" and "Viral infection" white blood cell count, that would be awesome.

Thank you

 

[Shipping News]

Technically a mycobacterium to be pedantic.


Sent from my iPhone using Tapatalk

Which is in Kingdom Bacteria, to be pedantic.

 

[operaman]

I was always taught this pattern too. My general concept for exams is that it stems from the mechanisms involved in eradicating the various pathogens. Anything attacked mainly through T-cells and the like (ie. viruses, intracellular pathogens, etc) will show a relative spike in lymphocytes. Bacteria are generally killed by neutrophils (think of all the dysfunctional neutrophil disorders and how those people get recurrent bacterial infections). Parasites are usually surrounded and bombarded by eosinophils, so a spike in them is often (at least on exams) suggestive of such a pathogen.

Terribly oversimplified, but easy to remember.

 

[ortnakas]

For test purposes, if you see a WBC diff that shows tons of lymphocytes and monocytes, your gut should be a viral infection, an atypical bacterial infection, or an inflammatory disease.

I just asked my Immunologist colleague about this and his two cents is that "lots of neutrophils = bacterial; lots of monos or lymphos = viral".

This is how we've learned it, too. Oversimplified for real life, but good rule of thumb for multiple choice. Things get funky in scenarios like meningitis, chronic infections, atypical bacteria, HIV that eventually kills off the lymphocytes, etc.

 

[masaraksh]

B. pertussis is a bacteria yet has a lymphocytic response. just in case anyone cared.

 

[Oo Cipher oO]

B. pertussis is a bacteria yet has a lymphocytic response. just in case anyone cared.

 

[sloop]

I think the better heuristic is that intracellular things tend to cause lymphocytosis while extracellular things tend to cause neutrophilia. If you think about the immunology of this, it makes sense and is an adaptive response.

 

[wjs010]

I think the better heuristic is that intracellular things tend to cause lymphocytosis while extracellular things tend to cause neutrophilia. If you think about the immunology of this, it makes sense and is an adaptive response.

This. This is an example of why TB would raise lymphos... Also if you know tb is granulomatous, you know it ain't neutrophils calling in those macrophages! It's T cells.