White cell count and intensive care unit outcome.

A high white cell count on admission to the intensive care unit (ICU) is generally perceived to be associated with severe illness and poor outcome, but the implications of a low white cell count are less well recognised. We retrospectively analysed data on 4,165 patients. The white cell count on admission was split into four categories, leucopenic (< 4.0 x 10(9).l(-1)), normal (4.001-10.0 x 10(9).l(-1)), leucemoid (10.001-25.0 x 10(9).l(-1)) and an exaggerated leucemoid response (> 25.001 x 10(9).l(-1)). The mortality of patients with leucopenia on admission to the intensive care unit was higher than those with normal or moderately raised white cell count (37.5% vs. 18.9% and 23.9%, respectively). A leucopenic response, as well as an exaggerated leucemoid response, is associated with an increased mortality.