Leucopenia Dr Sudarshan Pandit's Blood Plus Hematology Center offer treatment for Leucopenia Leucopenia is a decrease in the number of white blood cells, which puts a person at risk for infection. Normally when a person has infection or inflammation, the number of white blood cells increases so there are more cells to fight the infection with A low level of white blood cells in the blood, which can interfere with the ability to fight infection. Low white blood cell count can have causes that aren't due to underlying disease. Examples include medication side effects.