What is the significance of a low white blood cell count (neutropenia)?
We commonly find that our adult patients with Down syndrome have a mildly reduced white blood cell count. What does it mean? What do we need to do about it?
It appears most of the time that this is related to a lower production of white blood cells by the bone marrow (where blood cells are made). Although a low white blood cell count could be associated with an increased risk of infection, we don’t think that is what we are seeing in our patients but more research is needed. We regularly monitor the white blood cell count of our patients with a low white blood cell count and generally find it persists without additional problems. One cause can be medication side effect. We recommend reviewing the medications the person is taking.
We have sent some patients to a hematologist for evaluation particularly when they also have a low platelet count (platelets help with blood clotting) and/or anemia (low red blood cell count). In some individuals, the hematologist has recommended a bone marrow biopsy. In some individuals, by reviewing the blood tests and/or reviewing the bone marrow biopsy results, the hematologist has diagnosed myelodysplastic syndrome or possible myelodysplastic syndrome. We have not seen the progressive decline in white cells, red cells, and platelets in our patients with myelodysplastic syndrome or suspected myelodysplastic syndrome. For example, we have not had patients require recurrent transfusions due to this condition.
One of the concerns regarding myelodysplastic syndrome is the possible risk of developing leukemia. Studies have found a higher incidence of leukemia in people with Down syndrome. However, more recent studies have found that the incidence is higher in children; by late teens or 20s, this higher incidence is no longer present. Fortunately, despite seeing many adult patients with low white blood counts, it is extremely rare to see an adult beyond their mid-20s or so with leukemia.
Generally, we monitor the white blood cell count of our patients with low white blood cell counts. We usually do this annually or more frequently depending on the individual and their other history and physical findings. If there is a particular concern – the white blood cell count is dropping or particularly low, there are abnormal cells or a family history of leukemia – a consultation with a hematologist and a bone marrow biopsy may be in order.
If you are a person with Down syndrome with a low white blood cell count or you know a person with DS with a low white blood cell count, we recommend reviewing this with your physician/practitioner for recommendations. The information provided here should not take the place of a review with your practitioner.
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