If it is only a slightly low count, likely it is within normal ranges and lab error ranges.
If it is truly low, it might often have to be followed, since everything else is normal.
Any viral infection can slightly lower the count.
Autoimmune disease can to it, but then it would drop.
Medications can do it.
Hepatitis, HIV and some other infections
toxic chemical exposure
other autoimmune diseases like lupus
And other causes.
IT is an extensive list, that is if they keep dropping.
If you are otherwise healthy, not likely to be leukemia, lymphoma, etc. and not with normal blood tests.
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