CLL cells can collect in the blood, bone marrow, lymph nodes, spleen, liver and other organs.

If CLL cells collect in the bone marrow in large numbers they can stop the bone marrow from making enough healthy blood cells. This can cause:

  • Low numbers of red blood cells (anemia), which can cause fatigue or tiredness.
  • Low numbers of platelets (thrombocytopenia), which can cause unexplained bruising or bleeding.
  • Low numbers of white blood cells called neutrophils (neutropenia), which can lead to more frequent or long-lasting infections.

These infections can be life threatening.

CLL also stops the immune system from working properly, so that it:

  • Doesn’t react against bacteria and viruses as well as it should, making you more likely to have infections.
  • Can start to attack your body’s own blood cells, such as your red blood cells or platelets – this is called autoimmunity.