Adhesion to denture acrylic surfaces and relative cell-surface hydrophobicity of Candida parapsilosis and Candida albicans


Chair of Oral Microbiology, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong.


C. parapsilosis is an opportunistic emerging pathogen which together with C. albicans causes diseases in immunocompromised patients. Adhesion of Candida species to various surfaces is an important event in colonization and pathogenesis, and the relative cell-surface hydrophobicity (CSH) of the organism is a contributory physical force involved. Therefore, in vitro adhesion to acrylic surfaces and relative CSH of 24 isolates of C. parapsilosis and 10 isolates of C. albicans were studied. There was no significant difference in relative adhesion of C. parapsilosis isolates and C. albicans, although the former demonstrated a tendency for increased adhesion. There was significant intra-species variation in adhesion among isolates of C. parapsilosis (p=0.0001), but not C. albicans. In general, C. parapsilosis isolates demonstrated a two-fold greater relative CSH than C. albicans (p=0.0003). When the relative CSH of superficial and systemic isolates of C. parapsilosis were compared, the former showed a significantly higher (49.15%) relative CSH than their systemic counterparts (p<0.01). A highly significant positive correlation between adhesion and relative CSH of C. parapsilosis (p=0.74, p<0.0001) was also noted. Taken together, these data suggest that the attributes of adhesion and relative CSH of Candida species may contribute differentially in varying disease states of the human host, such as superficial and systemic Candida infections.