I have had a series of fluctuating white blood cell counts: in the 3.0 range then 2.5 then 4.2. should this be of concern? is this up/down normal?

Hematologist: Low white counts such as yours are not necessarily serious if your red cell series and platelet counts are normal. Occasionally this pattern is seen in connective tissue disorders like lupus, however. A hematologist is best qualified to evaluate and advise you and order the appropriate tests as well as arrange a proper follow-up schedule which is important.