Anaemia is the most common blood problem in people with SLE. It
is the lack of red blood cells, or the presence of red blood cells
that do not have enough oxygen-carrying capacity due to a deficiency
in iron or vitamins.
Anaemia is diagnosed using blood tests - the red blood cell count,
or the haemocrit.
In lupus patients, anaemia can be caused by chronic inflammation,
iron deficiency, prolonged uraemia, or haemolytic anaemia.
Red blood cells are produced by bone marrow, but prolonged inflammation
can hinder the production of red blood cells. When there is inflammation,
iron is not handled properly, and accumulates in the bone marrow
tissue. But iron is needed to produce haemoglobin (red pigment in
the cells), and if it is accumulating in the marrow tissue, it can't
be used to produce the red cells. Therefore, treating the anaemia
as one normally would with iron would be useless if the anaemia
is caused by inflammation. In these cases the production of red
blood cells would return to normal only when the inflammation is
treated.
Uraemia is marked kidney insufficiency in which wastes normally
excreted by the kidneys remains in the bloodstream. Uraemia can
cause anaemia in lupus patients, but can be treated with androgens
(male hormones), or with a hormone called erythropoietin.
Anaemia can also be caused by iron deficiency, which can be brought
on by heavy periods in women, or internal bleeding in the stomach
(which can be caused by NSAIDs). Treatment is with iron tablets.
Haemolytic anaemia is a condition where red blood cells are prematurely
destroyed. Red blood cells normally live for 120 days, but in haemolytic
anaemia, they only live for about 10-15 days. In lupus patients,
it can be caused by antibodies that are made against the red blood
cells. If other substances such as complement are present, the antibodies
can pop the red cells. It can be treated with corticosteroids or
cytotoxics, but in some cases, the spleen may have to be removed.