YES. Lupus can lower white blood cells.

What is a drop in white blood cells (called leukopenia)?

We can distinguish two types of white blood cells on the blood count, called a hemogram:

Polymorphonuclear cells, which directly destroy microbes and are part of our innate immunity,

and lymphocytes, which actively participate in the immune response, disrupted during lupus. These white blood cells can also become the target of the autoimmune reaction. This will therefore result in a decrease, called leukopenia.

What causes leukopenia in lupus?

In lupus, the most common leukopenia is a decrease in lymphocytes, called lymphopenia.  This lymphopenia, very common, is a criterion for classifying lupus, but it is not specific because many other diseases and treatments, such as immunosuppressants and corticosteroids, can also cause this abnormality.

A decrease in polymorphonuclear cells, called neutropenia, may also be seen during lupus, but we need to make sure there is no other, simpler cause, such as vitamin deficiency.

Neutropenia is also linked to autoimmune phenomena directed against polynuclear white blood cells.

A significant neutropenia can facilitate the development of microbe infections.

What should be done in case of leukopenia?

In practice, during lupus, most leukopenias (which are mostly lymphopenia) do not require any treatment. However, if lupus causes a significant drop in all white blood cells, including polynuclear neutrophils, and possibly other blood cells (red blood cells and platelets), it may be necessary to treat it with an immunosuppressant.

This drug aims to reduce the autoimmune response to allow the marrow to produce blood cells again.