Wbc fluctuates from 3.6 to a recent 1.6 and has been doing this for about a year. diagnosed with ra and had a bone marrow biopsy that was negative?

Yes, WBC of 1.6 is low and has to be further worked up as it can reflect side effect to current meds, an RA complication or completely unrelated conditions, such as an infection for example. Checking in with your treating rheumatologist would be best at this point.

You don't mention the levels of red blood cells or platelets. If these were also depressed the bone marrow would have shown an aplastic pattern. Since your bone marrow findings were normal this was not the case with you. Does the hematologist feel your very low wbc is the nonspecific type caused by autoimmune diseases like RA and you have no other hematology issues? That would be great.