Evaluation of the opportunistic microbial flora and of some antimicrobial factors in the oral cavity of leukaemic patients.

The occurrence of opportunistic pathogens and the concentration of some antimicrobial factors in the oral cavity of both acute and chronic leukaemia patients were studied. Enterobacteria were isolated from both dental plaque and crevicular fluid of all the groups examined, with few differences between healthy volunteers and leukaemic subjects; yeasts were found in both the crevicular fluid and the dental plaque samples of chronic leukaemia patients, but only in the plaque of healthy volunteers. Acute leukaemia patients did not have yeasts, but they were the only group colonized by the pseudomonads. IgA and N-acetyl-D-glucosaminidase (NAGase) significantly increased in chronic leukaemia patients compared with controls, whilst lysozyme seemed to present no marked differences for all groups. A further increase in NAGase concentration and an elevation in lysozyme content of saliva was observed for chronic leukaemia patients with severe periodontal lesions.