The only thing I know about neutropenia is in the context of people who have had their white blood cell counts wiped out by chemotherapy. If your count gets very low it can leave you quite vulnerable immunity-wise, but I doubt they would be that low just by natural occurence. What is your GP doing by way of further testing, or do they have an explanation for why they are low like that?
Neutropenia can happen as the result of a viral illness. If your immune system is down because you've had a run of illness lately your bone marrow can become a bit sluggish and that can result in a low white cell count. There are of course many reasons you can have a low neutophil count and it depends on how low it is. Some drugs can also cause you marrow to slow don a bit.
As Marydean says it can leave you a little vunerable especially to bacterial infection as the nuetriphils are important in fighting off invading bacteria in our bodies. Be careful if you get any cuts or broken skin, scratches and things like that. May sure you keep any wounds (no matter how small) clean and dry.
There are things that can help, olive leaf extract is a good one and of particular importance is the mineral zinc.
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