Asymptomatic oral carriage of Candida albicans in patients with HIV infection

Abstract

Objective: To assess the relationship of asymptomatic carriage of Candida albicans and clinically apparent thrush in patients with HIV infection.

Design: Prospective, longitudinal, controlled study.

Setting: The HIV clinic at St. Michael's Hospital, University of Toronto.

Participants: One hundred and twenty-seven patients with HIV-infection were divided into 3 groups according to the CD4+ lymphocyte count, and 37 healthy volunteers served as controls.

Interventions: Determination of blood type, baseline CD4+ lymphocyte count in patients with HIV infection, and immunophenotyping. Samples of saliva (2 mL) were obtained from each patient and control.

Main outcome measures: Carrier status, clinical presence of thrush, the association between carriage of C. albicans and blood type, secretor status and history of oral infection.

Results: In patients with HIV infection and C albicans colonization no correlation was found with blood type or secretor status of blood group antigen in the saliva. The frequency of oral carriage of yeast was greater in patients infected with HIV than in controls, but the difference was not significant for asymptomatic subjects with a CD4+ lymphocyte count greater than 500/microL. Persistent carriage of yeast and development of clinical thrush were associated with lower CD4+ counts. Clinical thrush developed only in patients with persistent asymptomatic carriage of C. albicans and CD4+ counts less than 500/microL.

Conclusion: The greater risk of oral colonization with C. albicans in patients with HIV infection partly explains the high prevalence of thrush found in this group.