Leukocyte function in the etiology of acute necrotizing ulcerative gingivitis.

Patients with the diagnosis of acute necrotizing ulcerative gingivitis (ANUG) and their controls, matched for age, sex, race and general plaque accumulation, donated blood for differential white blood cell counts and for assay of several leukocyte functions. The leukocyte function assays included polymorphonuclear leukocyte (PMN) responsiveness to chemotaxis and phagocytosis, and lymphocyte responsiveness to stimulation by nonspecific mitogens. The differential leukocyte counts were within the normal range for all subjects tested, and there was no difference between ANUG patients and controls. The ANUG patients did, however, display significantly depressed PMN responsiveness in both chemotaxis and phagocytosis, compared to the controls. There was also reduced DNA synthesis by ANUG patients' lymphocytes upon stimulation by a nonspecific mitogen (Con A). The data presented in this report suggest that depression of some host defense mechanisms, particularly PMN chemotaxis and phagocytosis, may be important in the pathogenesis of ANUG.