Neutrophil peripheral count and human leukocyte elastase during chronic lithium carbonate therapy.

Plasma levels of human polymorphonuclear elastase (PMN-E) are considered a marker of granulocyte activation and can potentially complement the periphe ral neutrophil count in laboratory and pathophysiological settings. Neutrop hilic leukocytosis is a well known effect of lithium therapy, but there is no information about the concomitant behaviour of PMN-E in these patients. The aim of this study was to evaluate both polymorphonuclear leukocyte coun t and plasma PMN-E levels in depression patients undergoing chronic lithium therapy. Absolute and differential leukocyte count in venous peripheral bl ood was determined by an automated method, and PMN-E evaluated by enzyme im munoassay. 39 patients (11 males, 28 females; mean age 43. +/- 6.02) with d epression disorders were studied, during lithium carbonate therapy. Neutrop hilia (neutrophil count > 7.500x10(9) cells per liter) was found in 7 (18 % ) patients and an increase in plasma PMN-E levels (PMN-E > 56 mug per liter ) in 6 (15 %) No correlations were found between neutrophil count, plasma c oncentration of PMN-E, plasma level of lithium and duration of therapy. The results show that in these patients, not only the PMN count but also elast ase levels can exceed the normal range. The absence of correlation between these two parameters suggests that the state of PMN activation is not linke d to their number in peripheral blood.